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2bzy7f | why do websites with countdown lists always make you click the next button instead of displaying it all on one page? | Is there some reason for this? It is so widespread on the internet, against all sensibility of having the countdown on one page. I have made it a practice of not using these kinds of websites anymore because I find the layout deserving of boycott. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2bzy7f/eli5_why_do_websites_with_countdown_lists_always/ | {
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"They get more page views, and therefore more ad revenue.",
"You click new pages, their ads reload, and they get more ad revenue. Slideshows made in HTML5 are far easier and look better, but the $$$ is what matters.\n\nBookmark this:\n\njavascript:(function(){window.open('_URL_0_);})()\n\nWhen you find yourself on a site like you describe, click the bookmark. It'll render all of it on 1 page for you.\n\nEdit: Working on that link so that it is clickable"
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3mulzp | why does a runny nose drip instead of coming out all at once? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mulzp/eli5_why_does_a_runny_nose_drip_instead_of_coming/ | {
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"Because snot is being produced continually. There's not a lake of it just waiting to all come out in a rush, it's produced slowly all across membranes in your nose and generally just runs out as its produced."
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3otqyk | why are republicans always to one to take the blame for extreme partisanship in the u.s. legislature? | It seems that by definition Democrats should be 50% to blame. Yet they always seem to be painted as the bipartisan party. Is this just media representation/internal bias (not that I am Democratic, I consider myself quite Independant). So what causes this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3otqyk/eli5_why_are_republicans_always_to_one_to_take/ | {
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"Republicans have decided, on the day of Obama's first inauguration, that they would do anything and everything to stop him.\n\nSo, they have spent most of the last 7 years doing absolutely everything to make him fail.\n\nThey now also have the Tea Party, a wholly owned Koch Industries subsidiary, where the best of the whackaloons are kept.\n\nIt's easy to say 'it's got to be 50% the other guys' but that's simply not true. The democrats haven't shut down the government for bullshit reasons. \n\nIt's like the old 'teach the controversy and let the students decide' argument in the never-ending evolution vs. creationism debate. One argument really isn't as valid as the other is. ",
"In general, US politics over the past few years have looked like this:\n\nDemocrats: Okay Republicans, let's negotiate.\n\nRepublicans: NO.\n\nDemocrats: Seriously, let's try and work out a deal.\n\nRepublicans: NO.\n\nDemocrats: We represent about half of the nation, we need to work together!\n\nRepublicans: NO.\n\nThe current Republican regime in Congress is refusing to negotiate. They are doing the \"We're going to just say no until we get our way\" tactic, which may win them points with the Republican voters who are also of the \"Negotiation means working with the enemy!\" mindset, but doesn't help the nation as a whole.",
"This is an example of what is known as false equivalence - the idea that two opposing viewpoints must be equally reasonable. Truth of it is, unfortunately the current republican congress has decided they aren't interested in governing. They have a core group of representatives who were elected on a platform of what might best be called revolution. They think (reasonably) that government is corrupt and beholden to special interests (it is) and the only way to fix this is to change everything. Unfortunately their method of change is to pull the house down around their ears. That's not a workable tactic and this is why they are taking the heat. It's one thing to want to change the government. It's a different thing to refuse to govern at all.",
"Your question is not unjustified as it applies t both parties. \n\nHowever, as a former Republican who was elected to local office in the early 1980s, I can tell you from experience that the GOP of today is not the GOP of the 1980s. The current divisiveness within the GOP is the reason why Congress is so stalemated and dysfunctional. I left the GOP to become an unaffiliated voter because of the growing extremism within the party. The GOP needs to split off these extremists and get back to the party it once was. We need to get back to the days of the Rockefeller Republicans who invested in social needs that business served in order to address the needs of the community and grow the economy. Where things got out of hand is that this growth was expanded under the myth of small government to privatize government services for corporate profit while paying the privatize sector employees less and maximizing profits. Its business intervening in government to get government to intervene in business to the advantage of the politically expedient business over its competition, customers and employees is supporting these extremists and others. It privatized the military to the point of outright fraud and a permanent state of war for corporate profit.\n\nIts what Bernie Sanders was referring to when he claimed an oligarchy controlled Congress via its lobbying and campaign financing. In reality we are all special interests and we have become so partisan since the Internet enabled a minority of extremists to sound like a majority and create such a long list of GOP presidential candidates who all seem to favor extremism in order to pander to the extremists. We all want change, but the thing that needs to change, but won't, is a political and governmental system that is controlled by the corporate oligarchy.\n\nThese extremists like to call me a RINO (Republican In Name Only) because they don't consider me conservative enough to fit their agenda. However, it is them that are the true RINOs because they are out to change what a Republican was. They know they cannot get elected in sufficient volume to achieve their agenda, so they infiltrated the GOP to gain control. Thus stalemating any action in government and blackmailing government when it cannot get its way by shutting down government."
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cmjumf | how do scientists around the world compare notes and/or eliminate duplication of effort when doing things like looking for a cure to a disease? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cmjumf/eli5_how_do_scientists_around_the_world_compare/ | {
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"Well first of all, sometimes they don't. Sometimes they compete. But more often than not, scientists researching a particular topic know each other (or at least of each other). And any research that isn't proprietary will generally get published to one scientific journal or another. Scientists researching a disease often get their start working for a scientist who was already researching that disease or something similar, so as a result you get a kind of loosely connected community. Additionally, cures aren't something that you work on as a singular unit. Oftentimes, you develop an idea about how a cure could work, then you may test it in test tube conditions. By the time that data gets recorded and possibly published, it's possible word has already gotten around about what you're doing, and that's before you've even gotten around to testing on mice and then people.",
"Usually they're either using different approaches, or they don't. It's not unheard of for research to be 'scooped'. Sometimes different research teams will, despite working separately, arrive at the same answer within months of one another. In such situations they sometimes team up and put all their names on the paper in question."
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2nmq1h | is there any merit to the idea that exposing yourself to germs strengthens your immune system? | Not in the way that exposure to the chicken pox at a young age "vaccinates" you later in life, but in the way that some people refuse to use hand sanitizer, or don't object to swimming or drinking unfiltered water, etc.
I know [this](_URL_0_) is an exaggeration, but it's along the lines of what I'm asking. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nmq1h/eli5_is_there_any_merit_to_the_idea_that_exposing/ | {
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"There is (edit: perhaps some) evidence (e.g. the studies cited [here](_URL_0_)) that being too clean gives your immune system too little to do, and can lead not necessarily to a weak system but a system focused on the wrong things (the body's own tissues).",
"_URL_0_\n\nThis is an article that addresses the connection between our weakened immune systems and our distance from biodiversity. \n\nI think you're asking whether germ theory or deficiency theory is correct.",
"No good evidence that recurrent infections strengthen the immune system in a significant way. And plenty of cases where a serious infection damages something (lungs especially) making you more prone to recurrent infections later.\n\nIts actually hard to find much of anything, besides just generally living healthily, that strengthens it (don't smoke, get enough sleep, avoid excessive stress).\n\nHowever - there is significant evidence that exposure to certain groups of organisms at a very young age may reduce subsequent allergy related illnesses including childhood asthma (exposure - not necessarily overt symptomatic infection). Search for the \"hygeine hypothesis\" and you will find plenty of papers. \n\nEdit - yes of course the immune system is \"strengthened\" such that with a recurrent exposure to the same infection - you will likely be immune or partially immune to it. But that is certainly not strengthening the immune system in general, which is what the questioner asked.",
"That's essentially how vaccines work. You are injected with a dead or weakened form of a virus that doesn't present a danger, but that your body's defenses will still recognize as a threat. Once recognized, there are molecules created to mark them for the white blood cells to know to destroy them. Once a virus had been \"marked\" by your immune system, it will recognize that virus in the future and completely destroy all traces of it before it has a chance to replicate itself and do harm to you. If you are ever infected with a live virus that you haven't been immunized against, the same process happens, but the virus has a chance to multiply and attack your cells before it gets recognized, which is why you get sick. But exposing yourself to one virus, e.g. influenza, won't make your body any more capable of fending off a completely different virus, e.g. Ebola.",
"Your immune system, every time it beats off an infection, stores information about that infection in it's \"memory B-cells.\" That way, if you get reinfected, your immune system can say \"aha it's you again! I remember your secret weakness from last time!\" instead of having to figure it out all over again. \n\nIt doesn't have to be a big infection for it to work; even a small infection will trigger and immune response. So yes, the more germs you are exposed to, the bigger your memory banks will be, and the less likely you are to get a serious infection from any of those germs.\n\nEdit: yes, I did say \"beats off\"",
"There is some research that eating your boogers helps your immune system _URL_0_ (see citations in wikipedia)",
"I think the idea is not necessarily that it strengthens it (though it might) but rather that it modulates it. For example, some people think that exposure to soil-based probiotics (SBO's) can lower your risk of asthma or allergies, which is where your body responds inappropriately to allergens. Others think it can lower risk of autoimmune diseases, which is where your immune system attacks your own body. If I had to guess why they think this is the case, I'd say it's because these problems appear to be unique to developed societies, whereas others living in more primitive societies who are exposed to a lot more soil-based organisms don't have to suffer these problems. While SBO's do appear to be beneficial, the reality is that you're exposed to more than just SBO's in daily life since you're in contact with human germs all day long as well. I personally think these immune system problems arise more from microbiome problems as a result of Caesarian sections, especially early in life, as well as diet. Can't say for sure, though.",
"Yes, in fact, exposure to pathogens actually helps keep some aspects of your immune system regulated. Appendicitis has a very low rate of incidence in countries that don't have access to clean drinking water, because the pathogenic load helps keep the function of the appendix in working order.\n\nFurthermore, there's good evidence that many allergies in the first world are due to the absence of parasites. Histamines are actually supposed to help remove parasites from the body, but, since the first world is relatively free of parasites, the body can develop sensitivities to things that it perceives to be harmful and cause allergic reactions.",
"Mice bred and raised in a sterile environment have much weaker, sometimes nonexistent immune systems. Foreign objects, like bacteria and viruses, stimulate the immune system. This causes the body to produce specific defenses against that foreign object (B cells, T cells, and antibodies) and nonspecific defenses called leukocytes aka white blood cells, like macrophages and natural killer cells, which constantly patrol the body looking for diseased and damaged cells to engulf and destroy. Without regular small invasions of foreign materials your body doesn't produce as many white blood cells, so when it gets a more serious infection, it takes a much longer time to generate an immune response and recover from the sickness.",
"Ok before the development of vaccine, it was documented that rubbing the puss from small pox into a deliberate wound of a healthy person would result in a more controlled form of the illness. So when the disease was sweeping through a unit, people that weren't immune sometimes would be exposed deliberately. On another note, I was raised on a farm, around every creature imaginable. I have no seasonal, animal, food allergies. I walked through animal manure barefooted, and would chew on clover buds in the field. My immune system is pretty sturdy. On the occasions I do fall under the weather it either dissipates quickly or I need to go to the hospital to get a tonsil abscess drained. If you have little ones expose them early on. It teaches there immune system to fight the real stuff and ignore the benign stuff. I'm referring specifically to animals and allergens. I'm pregnant and have a dog. The baby will grow up with a myriad of critters and sans hand sanitizer. ",
"[Exposing people with auto immune disorders to parasites can have beneficial results as well.] (_URL_0_)\n",
"We already do this in our everyday lives. In the past couple weeks you have probably visited your family doctor to get a flu shot, this vaccination artificially produces the virus, thus the immune system kicks in to eliminate it. And when it is eliminated you are left with the antibodies (the fighters), which will recognize the foreign invader again if caught.",
"I just finished studying asthma in one of my pharmacy courses. Some studies have shown that kids who lived on farms from a young age and were exposed to a lot of allergens were less likely to develop asthma because of this. Pretty interesting.",
"There is the flip side that infections are very likely causative agents in some people's autoimmune diseases (amongst other possible causes). \n\nOne ELI5 explanation being that infections can damage cells and release their contents, which exposes your immune system to otherwise contained self antigens, which can lead to memory B cells being created that target your own cells.",
"Me and my immediate family hardly ever get sick. Never sick enough to not go to work, and definitely never sick enough to not go out drinking with our friends.\n\nI grew up in the country. I spent my childhood years playing in mud, shovelling cow shit, and carrying 40-80 pound bales of hay.\n\nI also drank milk that went from our cow's udder, through a thin paper filter, and then directly in to my stomach.\n\nI don't know if this had anything to do with me never getting sick, or whether it's all in my families head....but when I have kids, I will be bringing them to the family farm as often as possible.\n\n",
"Well, think of it like this. If you're exposed to a small amount of *anything* that's easy and manageable, you get better at dealing with it.\n\nFor example, if you have a fear of heights, you don't immediately go to the top of the empire state building. Every day, you try to get more and more comfortable with places that are only slightly higher up each time.\n\nWhen you learn a musical instrument, you don't learn the hardest songs at first. In fact, you probably learn how to play a scale at first.\n\nIn the same vein, if you are exposed to a normal amount of germs at a young age, your body gains experience with learning to deal with germs.\n\nGo too far in the \"safe\" direction and you grow up in a sterilized environment, your body won't know what to do when it encounters new germs, and you'll acquire allergic reactions to harmless things.\n\nJust like how a pilot needs to practice and fail on a flight simulator, your immune system needs to practice and fail at a chicken pox simulator or a flu simulator to get ready to fight the real deal.",
"Yes absolutely. In fact, many people are now having issues with compromised immune systems because they spend to much time being too sanitary. Using antibacterial hand sanitizer often is not good for you, especially since you also kill good bacteria in the process. The idea of being exposed to germs strengthening your immune system is basically how vaccines work. Its generally a weakened or a part of the virus that they inject. Getting dirty when your young and healthy is natural and absolutely good for your long term immune health. ",
"There is some merit to the idea that if you expose yourself the bacteria and viruses you can build up a resistance to them. There are some exceptions: \n1. If you've never been expose you'll get sick \n1A. There are some bugs out there you do not want to catch, because it will be fatal, so washing your hands is still a safe bet. \n2. Some people are immunodeficient, this is most often caused by a genetic mutation. No matter how much they get exposed to bugs their memory cells may not work properly. Additionally, almost any infection leads to hospitalization and potential death. In these cases vaccinations do not help in the sense that if the vaccination is a dead virus they will not produce memory cells. If the vaccination is a live attenuated, they could get an infection. \n2A. There are varying degrees of immunodeficiency, sometimes there are a few antibodies (immunoglobulins IgA, IgG, IgM, IgD, IgE) that are missing or do not function correctly. This can cause prolonged infections and higher rates of infection. ",
"I've always wondered if this why I never get sick due to being in the military. Did I receive some special shot that made me immune to everything or was it because I was stacked with at least 12 other dudes at all times and my immune system just built it self up to laugh at any disease that enters my body.",
"I bet this thread won't be filled with anecdotes and pseudoscience to justify people's own gross habits.\n\nAaaaand it is.\n\nThat's not to say that there isn't truth to this, and some people aren't posting real sources, though.",
"Sometimes, but not always. SARS is equally if not more dangerous the second time you get it (provided you survived the first time). ",
"The \"Memory B Cell\" explanation is spot on. Small children are sick more often than adults because their immune systems are learning to fight off common viral and bacterial infections. Teachers, nurses, doctors, and those who are exposed to small children regularly tend to have more robust immune systems, as well; continued limited exposure to pathogens keeps the immune system \"awake\".",
"There's just no point posting this here, OP. These people don't know. You might as well go down the pub and ask.\n\nGo to /r/askscience if you want real information."
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4qodrq | why do homegrown plants need constant attention such as water or they will die, while wild plants are left alone and flourish? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4qodrq/eli5_why_do_homegrown_plants_need_constant/ | {
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"Wild plants die all the time. The ones you see are the few that lived - natural selection. They are outdoor so they get water from rainfall.\n\nIndoor plants are often from another region. They are constantly at \"room temperature\", something that no plant is naturally accustomed to, so we often get plants from climates that have milder warm weather or plants that are especially hardy. They must be watered because, being indoors, they get no water from nature.\n\nIn the wild, if the plant dies who cares, there are likely others nearby that live on. In a house, you have a single plant and want to make sure it stays alive.\n\nAlso, plenty of houseplants require water and care like once a week. That is not \"constant attention\" by any stretch of the imagination.\n",
"1) Wild plants die all the time, you just do not notice them. \n\n2) Homegrown plants are generally not native to your climate. As such they need more tending because they are evolved for a different environment and need you to simulate that environment to keep them alive. "
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cmolsk | how are ‘hybrid’ plants created? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cmolsk/eli5_how_are_hybrid_plants_created/ | {
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"Usually by controlling which plants get pollinated. Sometimes they will use a small paintbrush do it manually instead of letting bees and other insects do it randomly. It only works with closely related plants.\n\nBreeders will cross two plants with desired characteristics then select the crosses that combine the two for further interbreeding, while weeding out plants that revert back to the separate parental types.\n\nSometimes they will just breed two parents together and sell the resulting seed, repeating that each time new seed is needed. The first generation progeny (the F1 hybrid) will have predictable characteristics. Seed from cross pollinating those (F2 and subsequent hybrids) will turn out more mixed, with variations and throwbacks appearing randomly according to the statistics inherent in genetics."
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1fbwpy | why do humans throw up when they see something disgusting? | I know about the gag reflex but what triggers that reflex when you see something disgusting? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1fbwpy/eli5_why_do_humans_throw_up_when_they_see/ | {
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"I saw an article once that suggested this is an evolutionary response. Imagine life in prehistoric times, or maybe going as far back as the common ancestor between apes and men. Nobody knows which plants are poisonous and which ones are safe to eat. A bunch of us are sitting around eating and someone gets violently ill due to being poisoned. If we're all eating the same plant, it's too late for the guy who got poisoned but it might not be too late for the others. Those who get grossed out and throw up stand a better chance of not getting poisoned. Evolution selected for the ones who puked.\n\nUpdate: if you'd like to learn more and maybe answer some of the questions below, google \"sympathetic vomiting\" and also look at stuff related to the Area postrema, which is the part of your brain that triggers vomiting. Very interesting stuff. ",
"Surely it's fairly obvious. \"Disgusted\" is a reaction we feel to things that typically harbour dangerous bacteria: fecal matter, rotting carcasses, infected wounds. Vomiting is a natural reaction that prevents you ingesting life-threatening material.",
"Read The Storytelling Animal. It's take on how humans walk through scenarios in their mind as an evolutionary tool for preparedness may explain this. It's why we tense up or cry during movies. To the brain (and your body's response) looking at something happening can trigger a physical reaction because the story in your mind can be indistinguishable to it actually happening to you. It's a way of doing practice runs for surviving likely future scenarios, and this would be a side effect of this very useful tool. ",
"Well, not an answer to your question, but an interesting trick:\n\nSqueeze your left thumb gently but firmly in your left hand. You now have no gag reflex, enjoy! well, so long as you keep squeezing.",
"Humans normally would live together in large groups sharing food. \n\nWell, if your mom, sister and wife all start throwing up after eating your mushroom soup, chances are that those are bad shrooms. \n\nAs people lived and died, certain traits get passed along. At some point, the trait to barf when you see others all throwing up was helpful to keep us from dying. \n\nIf everyone else is barfing, you probably should too before you a are poisoned by what you ate. ",
"This might be a question better suited for /r/askscience. Because you're not looking for a simplified explanation of a complex topic, but just an answer to a question about biology. \n\nI know there's far too many comments in this subreddit admonishing posts for not fitting the criteria, but this comment is as much for the good of your question as it is this subreddit, because /r/askscience is likely to give you less speculative answers grounded in published research, and the sub is filled with actual scientists who would be better qualified to answer the question.",
"This does belong in r/askscience (more for the sake of a good answer than anything else)\n\nbut the answer anyway.\n\n-You have a big grey mushy thing in your head called your brain. \n\n-Right above your ear and slighty towards the front is an area of your brain called the \"insula\". \n\n-It's mainly responsible for taking \"tastes and feelings\" and putting them in a box called either \"approach\" or \"avoid\". \n\n-When it finds something it wants to approach, it signals another part of your head (details, details). \n\n-When it finds something it wants to avoid... it sends a message (motor signal) to the affected area to \"get it out/off\"!\n\n-This will result in rejection actions (like shooing something away, gagging, etc)\n\n/character\n\nI could go into way more details with insula signaling through cranial nerves that control glossophrangyl and vagus nerve systems (cranial nerves 9 and 10 are directly in charge of your gag reflex to directly answer your question) but this isn't r/science. I hope this is a sufficient introductory answer. ",
"Obviously you haven't been on the internet long enough if you're still throwing up when you see something disgusting.\n\nWould you like a tour? I'll even provide a 30 gallon trash can.",
"It's a common assumption that evolution is somehow \"intelligent\", in the sense that every trait an organism possesses must have a purpose which can be explained in evolutionary terms, that \"why does organism X have trait Y?\" is always a sensible question to ask.\n\nThis is false. It is true that a harmful trait is going to be selected against, but it is not true that that automatically results in the complete elimination of harmful traits (consider the wide range of inherited diseases a person can suffer from). Sometimes harmful traits simply aren't common enough or severe enough to be completely eliminated from an entire population, or perhaps less-severe versions of the disease confer some advantage (sickle cell anemia's connection to malaria resistance). Many other traits may be neither harmful nor helpful and so may simply hang around despite providing no particular benefit. In other words, while most of an organism's traits clearly help it survive, they don't all.\n\nBefore we get to vomiting in particular, let's start with disgust in general. Disgust is not unique to humans, but it is clearly much more highly developed in humans. Many animals will happily eat vomit, droppings, or weeks-old carcasses, things that humans would be revolted at the thought of doing. Now, disgust *does* carry a clear evolutionary advantage -- humans who found these things disgusting would be less likely to contract diseases from them, and the benefit of that is obvious.\n\nWhy are we more disgusted by these things than animals? I have seen it suggested that we are more vulnerable to food-borne illnesses than similar animals, due to having a relatively reduced digestive system. We have a reduced digestive system, of course, because we cook our food. We are unique in the animal kingdom in doing so, and cooking our food makes it dramatically easier to digest. With easier-to-digest food, we do not need as much of a digestive system to handle it. With a less capable digestive system, we are more vulnerable to getting sick from what we eat, but in a happy coincidence cooking our food kills the nasty organisms in it. So as long as we fully cook our food and start with clean, fresh kills, we're fine. Our disgust reaction to decaying carcasses becomes much stronger as a result, causing our ancestors to safely consume easy-to-digest cooked food.\n\nNow, the vomiting in particular? I suspect there's not a real strong reason for that, beyond \"disgust causes nausea (as a deterrent) and nausea causes vomiting\". There's not a really good reason why we'd vomit from being dizzy, either (that I know of), and I suspect disgust is the primary factor at work here rather than the vomiting itself.",
"It's an instinct to prevent you from even getting close to it or touching it because what we see as disgusting is likely to be dangerous to us.",
"when tribes roamed the earth in caveman days, they shared food and water... if one ate something bad, odds are they all did.... \nso if one person puked, it was an evolution advantage if others did too... the people that did not puke would keep in the poison and die...",
"Disgust in and of itself is a product of evolution. When we see someone we are physically repulsed and disgusted by, we tend to steer clear of them. One example of this is someone on public transportation who is matted with feces, or is obviously mentally unstable (or both!). It's in our best survival interested to stay away from them, either for their potential for violence, or the myriad of diseases they carry. Disease especially is a trigger for the adaptive disgust response\n\nBecause we had no refrigeration or knowledge of germs or disease, our bodies evolved to respond immediately and violently to that feeling of disgust. When other people vomit, it triggers that response in us. When we see a diseased carcass, same thing. It's to save us. \n\n[Check out this study for more info on it.](_URL_0_)\n\n**Like you're five**: That feeling you get when you see something REALLY gross like Jordan in your kindergarten class eating his boogers, or when you taste something that just doesn't seem right to you, like liver or that clam sauce Mom made last week, well that's your body telling you to be careful. It's like a little alarm bell in your body that wants you to be safe, and stay away from it. Mom will still make you eat clam sauce though. That's because moms are sometimes smarter than our bodies. But only sometimes. Sorry, kid. ",
"Do people really do this? I've seen it in plenty of movies and stuff, but I've never actually thrown up from seeing/smelling/whatevering something gross, and I've seen and smelled some things in my day.\n",
"Keep in mind most people (in the first world) have been highly sensitized to things like blood and organs and bodily fluids. When your normal day consists of cutting open another person and eating their organs (like in ancient South American civilizations), you might puke for other reasons.\n\n**tl;dr \"disgusting\" is subjective**",
"ok well while people seem to answer this question, there's nobody answering it like you are 5, so i will. \n\nWhen you see something disgusting you throw up because over time, out bodies have adapted to saving ourselves. If you eat poo (gross) you will puke because there are things in there that will kill you and your body doesn't want to die. Watching somebody else do this triggers an alarm system, like a fire drill.",
"The part of the brain that deals with taste is the exact same part of the brain that deals with disgust. So, we subconsciously imagine tasting whatever it is we're disgusted with.",
"this is a quality-ass question",
"So you don't eat it?",
"The vomiting reflex is controlled by the medulla in the brain. The medulla is a section contained within the brain stem, that controls unconscious or *involuntary* functions, such as breathing, swallowing, cardiovascular functions and vomiting.\n\nStimulation of these receptors starts the vomiting reflex. These triggers include drugs, chemicals in the Blood (alcohol), pain, stress, motion sickness, viral infections in the stomach, eating disorders, illnesses, etc. \n\nWhen the vomiting reflux is activated it causes a feeling of nausea. The vomiting center in the medulla sends signals through the body, which starts a wave of peristalsis (progressive wave of contraction and relaxation) in the small intestine.\n\nNow, what people see/feel can definitely trigger the vomiting reflex. I would consider seeing something particularly disgusting/horrible would trigger a stress reaction that would cause the reflex. \n\nI could see an evolutionary aspect to it as well. "
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2ks6zd | why do worldleaders even think about going to war with eachother even though they know that it will cost incredible amounts of money and many innocent lives? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ks6zd/eli5_why_do_worldleaders_even_think_about_going/ | {
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"War is usually about land and resources. If one country needs land for farming and it's taken by another country, they will not have the ability to feed their people. If land with valuable minerals or oil is taken, the country losing that land will have less ability to progress by using those resources. If a shipping lane is taken, some countries might even become trapped, unable to import or export goods. ",
"There's a difference in the reasoning behind wars in the past and in the modern era. In the past, some nations were led by people who were motivated by power (Alexander the Great, Ghengis Khan, etc). Sometimes wars were fought for land, food, or other natural resources such as gold, silver, diamonds. Sometimes we fought over over ideals and ways of living and governing (Cold War era of capitalism vs communism). Sometimes we fight to free ourselves from the tyranny of some far away land who claims to have control over us (American Reovultion). And sometimes we fight for people who can't fight for themselves. People who live in constant fear of dying or having their loved ones die to the hands of their oppressing governments.\n\nEvery war or conflict was motivated by some combination of the above and every leader who initiated these conflicts believed it was the right thing to do - either morally, divinely, or some other reason.",
"Any two individuals or groups are always going to have different opinions on various issues of common interest. When you go out to dinner, you need to balance your desire for sushi with your date's desire for pizza.\n\nMost of those differences are sufficiently minor that nations are willing to compromise in some fashion. However, nations frequently face problems that can't be solved by compromise - most notably when other nations refuse to negotiate in a meaningful sense.\n\nConsider the problem Japan faced during the run-up to World War II. The nation was busily industrializing, but it lack access to raw materials. It could only trade finished products for raw materials since it didn't have much in the way of resources itself.\n\nThis wouldn't have been a problem except for the fact that Japan was de facto locked out of access to most raw materials. The only place they could locally obtain them was Korea/China, and the Chinese had effectively closed their markets. Not only weren't they mining coal, but they wouldn't let anyone else pay them for the privilege either. The Western nations were generally anti-Japanese for racist reasons at the same time they were limiting trade in the kinds of materials that could be used for production of war materials (steel, oil, etc.)\n\nSince the combination of Western Imperialism and primitive, isolationist cultures effectively cut the Japanese off from raw materials, they were faced with a problem that couldn't be compromised away. They simply couldn't support their population and economy if things remained the way they were, and they couldn't negotiate with anyone who would help solve their problems.\n\nGiven this, entering a war they were very likely to lose was still a path that might possibly lead to a better future - while not entering such a war was virtually guaranteed to lead them nowhere.",
"War is either about territory or control of natural resources. Both of those are usually considered more valuable in the long run than the lives and the expenditure on war. Just to give one example of this, the US consumption of oil is 18.5 million barrels a day. At a rough $90/barrel, that's an expenditure of over $600 billion per year. If the US goes into an area to preserve control of oil traffic for the next 10 years, this is a benefit of $6 trillion. Now a war cost of $2 trillion and the loss of 5,000 killed and 52,000 wounded seems worth it, doesn't it? I know this presents a rather cold view, but I believe that's the calculation that is done.",
"Nature consists mainly of a brutal battle for survival at the expense of the other creatures competing for the same resources. Any organism without a strong instinct and ability to fight to the death did not make it to this point in the evolution of species. Genocide is normal and natural in this context. Our genes are programmed to survive and multiply at the expense of anything that gets in our way.\n\nGiven this biological inheritance, it's surprising that there are not more wars and genocide.\n"
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1x1mt8 | why does google safe search filter out anything sexual but leave very graphic gore images? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1x1mt8/eli5_why_does_google_safe_search_filter_out/ | {
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"I'm sure they could if they wanted to but that isn't where American priorities are at. We have this weird Puritan culture that has a fucked up relationship with sex. House wives all over would rather their children stomp hookers in GTA than see even a mild sex scene in a movie. While all of this is going on politicians and men of the cloth are consuming street-ass and devouring porn after long days of actively fighting sexuality in the general public.\n\nTL;DR: interesting question, I'm not sure"
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3pb8di | how is t-mobile able to afford people top use large ammounts of unlimited data while sprint and at & t have been found to throttle speeds. | With Sprint announcing they will throttle people who use over 23GB of data, how is T-Mobile able to have people use large amounts of data without throttling it?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3pb8di/eli5how_is_tmobile_able_to_afford_people_top_use/ | {
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"Very few people actually use very large amounts of data. T-Mobile is willing to let the few that do have it, because they believe that the goodwill they foster with their customer base is worth the traffic on their network. If everyone who had an unlimited plan used hundreds of gigabytes a month, they wouldn't be able to sustain it.",
"Data caps have very little to do with network congestion, they're about generating more revenue.\n\nCellular network congestion is a thing, but the real problem isn't **some** people using a **large amount** of data...it is a **large amount** of people using **some** data at the same time in close proximity. \n\nNetworks don't break down because your neighbors each use 80gbs a month, they break down because everyone at an event is trying to tweet at the same time. \n\nNow of course, abuse is an issue that does add strain to a network, but it isn't anywhere close to the issue that carriers would have you think.\n\nEdited for clarity."
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6qu6nr | why can't gifs be stored/compressed in the same way videos can? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6qu6nr/eli5_why_cant_gifs_be_storedcompressed_in_the/ | {
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"They *sort of* can. \n\nThere are clever gif making programs out there that make each successive frame in a GIF image transparent, and only make it contain parts of the picture that have changed from the previous frame. That is very basically how video compression works. \n\nThe standard answer though is that gifs define each frame in full, whereas video formats don't, they only define the stuff that's different on each frame. ",
"Because then they wouldn't be GIFs.\n\nA GIF is a specific image format that uses a specific set of techniques to compress an image and represent multiple frames. Those techniques are very cheap to decompress and thus was very good for the early internet when computers weren't very fast.\n\nModern video formats use several different techniques together for better image compression, most (all?) of which the GIF image format does not support. They also require significantly more computation to decompress, with several video formats actually using specialized hardware on your device or computer to play back as they could otherwise be too expensive to play back in real time!\n\nThe basic explanation of the GIF compression format is that it uses indexed color. A table of up to 256 colors is stored for each GIF with the pixels of the image only storing what color index to use. If multiple pixels in a row use the same color the format just stores the one color index and how many pixels after that use the same color. You can think of it as a digital paint by numbers.\n\nFor multiple frames of animation, each frame generally only stores information about pixels that changed from the previous frame, and uses a single \"transparent\" color for the other pixels. This can often mean much of each frame after the first is almost blank if not much changed.\n\nThen there's a little information about how long to display each frame and how many times to loop the animation, and that's kind of it.\n\nIt is possible to change or add to the GIF format, looping wasn't originally a feature for example, but there's little reason for anyone to spend the time doing so when there are other formats that already exist. It would also require getting browser and content authoring tool developers to support those changes.",
"GIFs were never meant to store video. It is an old format designed to store still images and small short animations. A 200 x 200 pixel half second animation was the most it was designed to store, and so GIF doesn't do well to store modern high resolution silent videos.\n\nIn video, most of a frame is the same as the frame before it. Most notably; in stationary shots, the background stays the same. To save space, you only need to store the changes between one frame and the next. This is the basis of inter-frame compression, and how modern video compression works. If something stays the same, you don't have to send it again.\n\nGIFs don't have inter-frame compression. It only has intra-frame compression. There was no need for it back when the format was designed. Each frame of a GIF is compressed by itself, without taking into account information from the frame before it. So whichever part of the video stays the same between frames, has to be stored again each frame. This makes GIF a much less compressible format for video than other alternatives.\n\nEdit: Had inter and intra backwards."
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2b70cb | why are cops portrayed so overwhelmingly positive in all tv show procedural? they are all morally upstanding, caring, really really competent, hard working to the point where their personal lives are in turmoil and good looking to top it all off? | I know there are many good cops but even they aren't as near perfect as they are portrayed in pretty much any of dozens of TV Procedural. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2b70cb/eli5_why_are_cops_portrayed_so_overwhelmingly/ | {
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"Because shows portray everyone that way.\n\nThey portray doctors that way, judges, models, chefs, factory workers, teenagers, etc.\n\nUnless it's one that has to be sad/depressed/angry for a specific plot, then everyone is generally portrayed as having an enjoyable life even when realistically, they don't.",
"It's TV. If you want reality, watch documentaries, or go outside. Everyone on TV is portrayed in a 'best light', and by an attractive actor. Doctors don't all look [McDreamy](_URL_7_), cops aren't all like [Horatio](_URL_4_) or [Munch](_URL_0_), hackers aren't like [Morpheus](_URL_1_), the woman processing government pension checks doesn't look like [Mary Louise Parker](_URL_3_), and my landlord resembles neither [Schneider](_URL_5_) nor [Buffalo Butt](_URL_2_). \n\nOccasionally you'll get a character like [Valchek](_URL_6_) from The Wire, but television is usually about limited characters in contrived situations that all neatly get wrapped up in an hour. \n\n",
"This is a loaded question, and you can't prove 'all' TV shows portray this ",
"The Wire certainly shows police aren't perfect. It's also an awesome series. "
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"http://www.imdb.com/title/tt1245526/fullcredits/",
"http://www.imdb.com/title/tt0313043/",
"http://wikipedia.org/wiki/One_Day_at_a_Time",
"http://flavorwire.com/226049/tv-cops-you-wouldnt-want-solving-your-crime/6",
"http://abc.go.com/shows/greys-anatomy"
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1exudt | how do home theatre systems convert stereo sound into simulated surround sound? | I have a 5.1 surround sound system. Whenever I send a TV show that I know has stereo sound to my television, it is able to accurately convert it into a sort of 'simulated surround sound'. When I turn off my front 3 speakers, I can hear background noises (for example, the background sound of people talking in a diner).
It is also able to guess which sounds should be moved from the rear speakers to the front speakers. For example, during a car chase, it's able to put the sound of an oncoming car through the rear speakers, and then as it passes, it moves it through the front speakers.
It does this incredibly accurately, but how does it do this? How is it able to differentiate the different noises and properly put each sound to a different speaker?
Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1exudt/eli5_how_do_home_theatre_systems_convert_stereo/ | {
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"Chances are, the stereo sound of the TV show is encoded in Dolby Pro Logic stereo. This is also the method used in Dolby Stereo in movie theaters (before the advent of digital sound, that is). It is a way to mix four channels of sound as two and then unmix them into four channels again.\n\nIt works like this. A sound that should sound louder in the right channel is recorded louder in the right channel. Left, left. A sound that should come from the center channel is recorded *equally* loud in the right and left channels.\n\nSo far, this sounds like ordinary stereo, doesn't it? Here's the interesting part. A sound that should come from the surround channel is also recorded equally loud in the left and right channels--but *out of phase*. This means that as the cone in the right speaker is pushing out, the cone in the left speaker is pulling in. Usually, they move in and out in sync.\n\nAnd here's another interesting thing: even if you don't run the sound through a receiver that has Dolby Pro Logic, you still get a kinda-sorta surround sound, because the out-of-phase surround channel sounds will be diffuse and non-directional. It's kind of crummy compared to actual surround sound, but it's still rather more than just two channel stereo.\n\nBack to Dolby Pro Logic. All this means is that there is circuitry in the receiver that analyzes the signals in the left and right stereo channels and *steers* sounds to the appropriate channel. A sound that is clearly louder in the right or left channel goes right or left, a sound that is equally loud in both channels is steered to the center channel, and a sound equally loud in both channels yet out of phase will get steered to the surround channel.\n\nThe major drawback with Pro Logic is crosstalk. Sound meant for one channel cannot be completely eliminated from the other channels--surround effects will still be audible in the screen channels, dialog will be audible in the left, right and surround channels--but it's still pretty nifty. One reason digital sound became popular in theaters, aside from *more* channels, is that the channels are entirely separable, that is, \"discrete.\""
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1fdet4 | what really happens when you get a blown motor? | My car recently got a blown motor and I have no idea what that really means beyond the point of "Hey your motor won't work, get a new one."
-edit-
The way my engine blew was lack of coolant and oil from a cracked head. So, if my engine had run without coolant for long enough to have it go out, what really happened inside is what I'm asking. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1fdet4/eli5_what_really_happens_when_you_get_a_blown/ | {
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"That could mean a lot of different things. The timing belt could have snapped, causing the pistons to hit the valves. A connecting rod may have broken due to a spun bearing, punching a hole into the block as a result. Blown really just means irreparable damage, but it doesn't tell you what broke. And if it's an older car, a mechanic may also tell you the engine is blown when the damage is technically repairable but it's cheaper to buy get a used a remanufactured one. ",
"Actually if you run em without coolant it will sieze, some engines will start again once cooled but still have damage. But most will pretty much weld the pistols inside the block. If your not familiar with the internals of an engine it's hard to explain. But someone saying your engine is blown could mean a ton of different problems.\n"
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p74wu | if facebook made 3.71 billion usd in 2011, why would they want to sell their company instead of keeping future profits for themselves? | I don't understand the benefits of an IPO for a company that is profitable. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/p74wu/eli5_if_facebook_made_371_billion_usd_in_2011_why/ | {
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"People are willing to offer far more than Facebook is worth right now, which means it's a good time to sell. In the mean time there are lots of profitable things to invest in, and if it gets cheaper later, then you can buy it back with a profit.\n\nEdit: I should also mention that they're only selling about 5% of the company, and keeping the other 95% for themselves.",
"Because now they are making profit on how much the company is worth, not the company itself. The [wikipedia page](_URL_0_) on this subject kinda helps. In addition, the [past answer](_URL_1_) on stocks helps. \nThe way I understand it, right now the company is making money buy selling stuff, in this case the ads on the website. This is fine and all, but you can only sell so many ads, eventually the income is going to flatline. If you take your company public, people now can buy pieces of it. Initially, this money goes straight to you, since you are selling it. Now you have a bunch of money to use to do improvements and make the company worth more. The more your company is worth, the more people are willing to pay to get a chunk of it. Of course, eventually you aren't really the owner, but the person in charge per se. However, now the company hopefully has a bunch of money to work with that isn't just its original revenue, and you can get paid a big salary for being in charge.\nI'm certainly no expert, but this is how I have come to understand it. ",
"Say you own 10% of facebook. The 100 billion number that people are using right now values your ownership at 10 billion dollars.\n\nBut you don't actually have that money. The valuation could plummet and you'd never see it. So to mitigate the risk of that happening, you \"cash out\" one-tenth of your stake (or 1% of the company).\n\nNow you have a billion dollars, cash, in the bank. It's no longer tied to something as volatile as a corporation.\n\n\nThe other reason is that maybe the company needs some cash to spend on operating expenses, expansion, etc. Either the way, the purpose of an IPO is to convert theoretical value into cash value.",
"Great answers here already. One more though. Facebook is having significant legal issues with the SEC stemming from how they have let investors buy into the company before the IPO. They would be expected to have to release their books anyways this year, they are just going to profit on it as well now by selling a small portion of the company publicly that they otherwise would have sold to those private investors"
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946q4q | why do foods with a more basic ph give me heartburn? | Why would something like orange juice (3.5) make me feel acidic if my stomach is already 1.5-3? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/946q4q/eli5_why_do_foods_with_a_more_basic_ph_give_me/ | {
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"The pH is not the only thing contributing to the acidity. The type of acid also matters. Your stomach fluid is around 10% Hydrochloric acid. Most fruits contain C-vitamin (ascorbic acid) and citric acid. These contribute differently to the acidity in whole. Different acids have different charasteristics.\n\nFor an example[ Aqua regia](_URL_0_) can corrose even gold and platinum, but it's components, when separate, (Hydrochloric acid and nitrogen acid) cannot."
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3ae8cn | how they create and maintain millions of activation keys for software and especially games (like on steam) without complications | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ae8cn/eli5_how_they_create_and_maintain_millions_of/ | {
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"It isn't really all that hard.\n\nAn activation key is just a (somewhat) random assortment of numbers and letters (usually 16). All you would need is a basic random value generator to create a few million unique codes, enter those codes into a database, then set a program in the game so that when a certain action is taken (ie - the game application is opened on a machine) it sends out a query via the internet to this database and checks against the list... if there's a match then no problem... if there is no match... a problem.",
"Some activation keys are also algorithm-based. These are not tracked with a database. Rather, a calculation is performed to validate a particular key. It may be random or based on something like a registration name/ID."
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4o43vh | why did soldiers in the 1800s put their ears to the ground to hear enemies approaching | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4o43vh/eli5_why_did_soldiers_in_the_1800s_put_their_ears/ | {
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"Because the shockwaves of the boots and wheels of approaching enemies travel further through the ground that the audible sound does through the air. Edit: The Wabes have been eradicated!",
"Sounds travel well in some solids. Cavalry makes a lot of impact noise, which can sometimes be heard through the ground over long distances.",
"The Indians (native americans) used to lay their ear on the traintrack to hear if a train was comming so they could ambush them.",
"I think the better question is, why wouldn't they? You seem to acknowledge that they can in fact hear enemies approaching. That seems like good information to have."
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2gb7mz | what about water makes bed head go away? | I could put gel in my hair and it wouldn't make bed head go away but when you rinse your head it's all gone. What is it about water that does this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gb7mz/eli5_what_about_water_makes_bed_head_go_away/ | {
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"Hydrogen bonding! These are attractions between the oxygen and hydrogen of separate water molecules, because of electromagnetic force. It may sound complicated, but basically, it's what makes water \"sticky.\" When you dip your hand in water and it comes out wet, or water sticks to itself in beads, or when two wet sheets of paper cling together, that's what I mean. \n\nThe curliness/waviness of hair is highly affected by hydrogen bonds. These bonds are the same as the type between water molecules, except that they are between hair molecules. So, water makes hair a \"clean slate\" by interfering with all these bonds and letting them reform anew. This is why women set their damp hair in curlers and it comes out curly, while putting dry hair in curlers won't do anything - the water destroys the arrangement of hydrogen bonds in the hair, and when it evaporates the hair reforms its hydrogen bonds in the way that it's curled. Without curlers, simply wetting your hair and letting it dry will allow the hair to bounce back to it's natural shape. So, when the shape of your hair has been altered by spending a night smashed on a pillow, water is the best thing to restore it."
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1edpue | when drinking, why do i feel sober after puking | If the alcohol is in my blood, why do I immediately feel "sober" after puking (while drinking, not day after)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1edpue/eli5_when_drinking_why_do_i_feel_sober_after/ | {
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"Don't think you feel sober, you just feel like you can drink more since your stomach is empty.",
"You might be confusing feeling 'sober' with feeling 'better'. Before you puke you probably feel awful, your body's way of telling you that you've got too much in you and it's time to jettison some of it. \n\nOnce you do vomit and get some of the alcohol resting in your stomach out, that feeling of being bloated, sick, etc. goes away. ",
"you don't feel sober. you feel less sick, so by comparison your (slightly) improved condition feels like sobering up. you're still very drunk though. puking doesn't lower your blood alcohol level. ",
"Here is the correct answer: When you throw up, your body releases endorphins and adrenaline, which are two substances that your body releases when it is under sudden and/or physical stress. The endorphins are like your body's natural pain killer, and adrenaline boosts the supply of oxygen and glucose (energy) in your brain and muscles. \n\nUnfortunately, these things wear off eventually but they, together with the fact that by throwing up you have decreased the amount of poison (alcohol) in your body combine to make you feel better.\n"
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9t06i7 | light travels at a constant speed in a vacuum. how do we not know our absolute speed in the universe? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9t06i7/eli5_light_travels_at_a_constant_speed_in_a/ | {
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"Because relativity is weird. If we did exactly as you proposed, we would measure no difference in any if the beams. If we launched the detectors at thousands of miles an hour off in a direction and measured again, we *still* wouldn't detect a difference.\n\nThis is because light always moves at a constant speed when you measure it. Doesn't matter how fast you're going, you'll still measure the same. In fact, if you were moving and shot off a light ray, bounced it off a stationary target, then recorded it, both you *and* the target would measure contradictory speeds for the light ray. Both of you would detect that the ray was moving exactly at C relative to each of you despite the apparently contradiction.",
"We have done exactly that, and that is one of the ways we proved there is no such thing as \"absolute speed in the universe.\" The reason is that light travels at the same speed relative to us regardless of our motion. It also travels at the same speed relative to anyone else. This sounds like a paradox but it is not, since time and space are *not* constant - different observers will not agree on distances, durations, or the order of events. The resolution of this \"paradox\" is called special relativity, developed by Albert Einstein.",
"Light travels at a constant speed in vacuum regardless of how fast you are moving. Imainge a rocket ship with headlights in the front. It goes by you at 99% the speed of light. Intuitively the people in the rocket ship will see the light from the headlights tracel at the speed of light. Unintuitively, you would ALSO see the light travel at light speed. You do *NOT* see the light travel at 199% the speed of light.\n\nThis is weird, but we are very sure now that it is what happens in our universe. It is also the cause of a lot of the weirdness in the relativity. That is why the theory of relativity is called that. There is no such thing as an absolute motion. All motion is relative.\n\nOn a somewhat side note:\n\n > fire off six or more rays of light in space nearby, measure how fast they travel in certain directions, and use that to measure the absolute total speed of our solar system/galaxy.\n\nSomething like that has been done before. You can look into the [Michelson–Morley experiment](_URL_0_), which tried to find out speed through a theoretical aether that exists everywhere. The expriment did not measure any difference in the speed of light in different directions. And it was evidence that the aether did not exist, and also evidence for the constant speed of light in all reference frames.",
"We have tried to do that. Multiple times even. We know the Earth moves around the Sun and Sun moves around the galactic center and our galaxy moves as well, so we were expecting to find that if we measure lightspeed in one direction, we'd get a different result than in some other direction.\n\nAs it turns out, no matter how fast you are going and in what direction you measure the speed of light in a vacuum, you always get the exact same value.\n\nThat's the core thing about relativity.",
"Light travels at the exact same speed in all directions, according to every observer, regardless of their relative speeds. \n\nLets say we have a central observer who sees I’m in a spaceship moving towards you at 0.25C and sees you’re in a spaceship moving towards me at 0.25C, so to him we’re moving towards each other at half the speed of light. Now I turn on a laser pointer and shine it at your ship. To me, that laser moves away at exactly the speed of light. To you, that laser will approach you at exactly the speed of light. And to the observer it is moving from my ship towards yours at exactly the speed of light. It doesn’t matter that our relative velocities are all different, light, in every frame of reference, always travels at the same speed (so does any massless particle). It doesn’t make intuitive sense since that’s not how velocity works in any situation we can actually see here on earth, nor is it noticeable since everything we do is WAAAAAAAY slower than the speed of light. But at relativistic speeds (speeds that are a sizable fraction of the speed of light), time and distance behave differently depending on how fast you’re moving. "
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3n540b | what would happen if the us just adopted all of australia's gun policy laws verbatim? | Change the geographic locations referenced but keep everything else exactly the same. What would happen? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3n540b/eli5_what_would_happen_if_the_us_just_adopted_all/ | {
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"In the long term gun violence would be reduced, but due to the fact that there is such a huge volume of legal AND illegal guns in the US there would be a long adjustment period where citizens have no real access to guns but criminals can still get them pretty trivially. Its not difficult to think this transition period might get quite violent. It could be a decade or more before the supply of illegal guns is stemmed to the point it is in AUS where acquiring a gun illegally is prohibitively expensive for common crooks.",
"A country cannot just 'adopt' gun laws without a lengthy legislature process.\n\nLengthy legislature processes cannot be carried out unless a majority of representatives vote in favor of it.\n\nA majority of representatives will only be in favor, if the majority of their voters in their counties are in favor of putting them in office.\n\nAnyways, if all of that happened, there are still 320 million guns in the USA. They don't just poof and disappear. 320 *million* firearms would still be out there and in the possession of millions of people. Short of a SWAT-team raid on every home in the country... there will always be guns in the USA.\n\nIn any case, many of our stricter states (such as my state of NY) are very much on par with the Aussies. Very difficult to get a handgun here.\n\nNot to mention that 3D printed guns are a real thing.",
"At a moment it's hard for anyone to be reasonable but to beat the dead horse a bit more, gun violence IS down and continues to fall. This doesn't make the news as much as shooting, but good news doesn't sell newspapers. Also I don't see any reason to follow the Australians in anything.",
"I believe that the majority of Australia's gun laws were implemented directly following a national tragedy over there. Which caused the large majority of people who had owned guns to voluntarily give their gun to the up to the government.\n\nTrying these same laws in the US would not work because there would be way more people who would not willingly hand in their firearms. Making them illegal wouldn't do much, since they would still be widespread and fairly easy to get. "
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3v6g5j | why do countries prevent regions/states from seceding? | I don't think people who are defeated in a secession struggle will ever be really happy with the state. So what's the point in keeping unhappy citizens in your country?
edit: two answers so far suggest that a country loses resources if regions secede. Doesn't this suggest that governments are more interested about self-preservation than they are about giving people what they want? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3v6g5j/eli5_why_do_countries_prevent_regionsstates_from/ | {
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"When a country loses territory, it loses people and resources. That makes the old country weaker than it was before. Also, if the people in the new country are hostile towards the people in the country that they left, the old country suddenly has a new enemy directly on its borders.\n\nThat being said, sometimes both sides do agree to secession. One example is the breakup of Czechoslovakia into the Czech Republic and Slovakia."
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rygkm | easter | Seems to me like a free long weekend to everyone except the hardcore religious. Explain to me, as somebody who knowns next to nothing about Christianity, why it's so important. Regardless, I don't mind four days off school. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/rygkm/eli5_easter/ | {
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"In Christianity, the week leading up to Easter, Holy Week, has a service each day, representing some part of Jesus's work in the world. Good Friday, the last weekday of Holy Week, represents the day in which he was crucified. It is very solemn. Three days later, Jesus rose from the dead. If Friday is one of the three days, Sunday is the day Jesus rose from the dead, fulfilling the scriptures and proving that he died for our sins. \n\nTL;DR: Easter represent the day Jesus rose from the dead, proving that he died for our sins. ",
"Pretty much, Jesus died on Good Friday, so people were all like \"Man, that's saaaaaaaad.\" so a couple days later some females went to go check on where Jesus was entombed(nosy bitches) and When they got there, they were like \"Awwww shit, Jesus gone.\" Okay, so then Jesus came back from the dead 3 days after Good friday(Easter) and he was like \"Surprise Bitches, im the Hulk, I moved that big ass rock by myself\" and thus proving that he died for our sins.",
"In full disclosure it should be mentioned Easter, like many religious holidays, predates the religion, and is simply the Christian cultural celebration that emerged out of similar religious holidays from various religions, notably Judaism. It was given a Christian focus at some unconfirmed later date, but almost certainly some point before the First Council of Nicaea (A christian convention around 325 CE) as it was a topic of discussion there.",
"St. Peter was actually a rabbit."
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8en296 | why can't you move your leg and hand in circle in opposite directions simultaneously? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8en296/eli5_why_cant_you_move_your_leg_and_hand_in/ | {
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"You can. You just have to practice.\n\nYou spend an entire life teaching your muscles to remember certain moves. Standing up seems easy to you, but watch toddlers do it sometimes and you're watching \"muscle memory training\" at work.\n\nYou don't have much call for moving your leg and hand in opposite directions simultaneously, so it can seem hard to do. But work on it and you can. You just need to train it in.",
"In fact, some people can do that. But it takes a bit of training. We have difficulty performing these two different movements at the same time because the area of the brain that commands these movements is the same for your leg and your arm.",
"I don't know what you mean, I can do this?"
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7q8q7f | what is 'sharpness' and how does serration affect it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7q8q7f/eli5_what_is_sharpness_and_how_does_serration/ | {
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"Sharpness is correlated to how thin the leading edge of a blade is. The thinner the edge, the easier it can wedge between other materials and thus cut them. Serration is also used for cutting, but instead of relying on a thin edge to cut, the teeth physically dig in and pull on the material, tearing it. Serration is good for tough, fibrous material that might otherwise flex under the pressure of a straight edge. But for softer materials, serration can produce a rough, uneven cut."
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3spwfq | why is paris being repeatedly subject to terrorist attacks? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3spwfq/eli5_why_is_paris_being_repeatedly_subject_to/ | {
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"There are no answers to this yet, and there won't be for some time. Modern communication is fast, but not that fast. Watch the news and read the news sites like everyone else.",
"Assuming it's ISIS and affiliated (let's be honest, it's not like we have international terrorrists outside of them, so 99% sure)\n\nFrance has a habit of having a military presence in northern africa/dictatorship/ancient colonies, and has been bombing ISIS for months with some success. \n\nAlso, the separation of church and state is quite heavily enforced, and because islam has been the \"new\" religion around here, it's the one that saw the most pushback to its expansion, as the country is fairly non/anti-religious. \n\nOther major monotheism are quite established, and islam is in the population, but not that much in infrastructures (having troubles to get prayer rooms, convention halls, no one want 30m tall a minaret in 18th century european cities). They also made a push a few years ago to get more stuff (pool access restricted to woman, hijabs, religious slaughter etc) Didn't went well, as many of these things did brush the christian/jewish/atheist population the wrong way (for different reasons obv). Anyway, for some reason, that marked the country as fairly islamophobic. \n\nSo, TLDR : France is present in NAfrica, conducting military operations against ISIS, and the expansionist nature of islam isn't well received in a country where the norm is \"don't even try to change my shit to accomodate your religion\".",
"They are the capital city of one of the world powers that is a permanent member of the UN security council. They also provide a lot of UN police force troops. ",
"Higher percentage of Muslims due to influx in immigration, combined with the French progressive attitude that some immigrants are uncomfortable with handling (it never existed in their home country). \n\nThey become offended because it's not how they were raised, and want to change it violently to their own terms. ",
"Doesnt France have most muslims out of eu countries?",
"The situation and why France is a target is quite complex, and unfortunately your're going to get largely \"because Muslims hate progress\" answers. But reality is it's not quite that simple. Part of the issue is that France, while it tries to claim it's progressive, is really not. This question/answer already goes over the issues going on within France: _URL_0_\n\nSo you have France, which is progressive but also has this uncomfortable underlying racism that it would rather not admit to, and you have immigrants realizing that France sucks for them but can't really go anywhere else. Throw in extremists capitalizing on this situation by convincing young men that the situation will never change unless they blow shit up, and you have terrorism.\n\nAnd what the \"Muslim's are bad, M-kay\" brigade doesn't realize is they contribute to the recruitment of Muslims by painting the entire religion with the same brush. \"There are Muslim extremist terrorists, so therefore all Muslims are extremists.\"\n\nThey fail to realize there are also violent white rightwingers and they'd really hate it if we said anyone who was a right wing conservative in the US was a domestic terrorist due to McVeigh.\n\nSo, just remember things are not as simple as people wish they could be.",
"Because the multiculturalism melting pot that governments promote never happens. Large immigration causes pockets of sub-cultures to grow. Tensions between those cultures are imported and thrive. ",
"Deport all without valid visas, documentation. Why is it that their countries of origin have zero compunction about exercising the most extreme xenophobia, yet \"first world\" countries are supposed to suffer the slings and arrows of outrage from displaced zealots who contribute nothing to their adopted homes, and radicalize this way?",
"For years they allowed immigration from Muslim countries. Then turned over huge neighborhoods to them. It's not the PC narrative to say the truth. But large percentages of Muslims agree with terrorism in the name of Islam. They may not want to commit terrorism themselves but they will look the other way as others do. So a small number will actually carry out the attacks but many others will say nothing as they plan the attacks. So France has invited this problem in and the rest of Europe is doing the same as we speak. Trying to understand Islamic extremism is difficult and simple at the same time. It's difficult if you are sane because why would anybody want to kill strangers because a book written by a pedophile 900 years ago tells you to? But it's simple because they don't want to kill you for any other reason than you are not one of them. ",
"Hi/Salut!\n\nThis is a good question. First, I would say that while France has certainly made the news the past few years, there are a lot of terror attacks everywhere. Just look at [this list for the US](_URL_0_), compared to [this list for France](_URL_8_), and you'll see that there are people that want to cause terror everywhere. It's important to keep this in mind when discussing responsibility for these attacks, and to not paint in broad strokes.\n\nThe real answer is that it's complicated and nebulous, as most things are. But, let's focus on just the past year, where there have been a number of attacks and incidents involving Muslims. France has a long history with colonization, specifically in North Africa, but also in the administration of Syria and Lebanon after the end of the Ottoman Empire. Though colonialism is officially over, these ties remain and encouraged immigration to France from these places for many years. This has lead to a large population of Muslim heritage (around 7.5% or ~5 million according to [this report](_URL_2_)) living in France today. It might seem like a lot, but that's not specifically those who practice Islam but just those with Muslim heritage. Even so, [there are more practicing Muslims in the United States](_URL_6_), so maybe it's not just to do with Islam itself. \n\nOften brought up is the poor integration of this Muslim-heritage population. Metrics of integration are hard to come by, but there are several ways we can look at it. Unemployment rates for immigrants from outside the EU are [significantly higher](_URL_3_) than those for the general population or even EU immigrants. So while this might not be exactly the same for descendants of these immigrants, it's not unreasonable to assume that employment discrimination might be present for people who look and have similar names to these immigrants (I have no specific data to back this up). \n\nThere's also a decent amount of [Islamophobia in France](_URL_1_), and while this is a chicken or the egg situation (do attacks lead to Islamophobia or vice-versa - probably both), it does not help the integration of migrants or subsequent generations. The Islamophobia comes from all levels, including quotidian interactions (my observations) and politicians like [Marine Le Pen](_URL_5_) and far right leaders. France is not particularly welcoming to these groups, and so often they rely on their own communities for support.\n\nFurthermore, France is involved in military action in [Syria](_URL_7_), [Iraq](_URL_4_), and other campaigns across the Arab world, which makes it a target of terror groups from those regions.\n\nSO, in summary, France has a relatively large population of Muslims and their descendants. These people face discrimination at many levels in France, hampering their integration into French society, even for generations. Furthermore, France is actively involved in anti-terror and military actions in the Middle East. Together, this gives terror groups a vulnerable, disgruntled, and excluded population in France that they can exploit, and who have not found France to be welcoming or a home for them.\n\nA few clarifications: this is largely my own speculation, but it's been echoed elsewhere. I'm sure people with degrees on the subject can correct/clarify/repudiate what I've said. Also, I want to say that this is no way is meant to condone any of the attacks. What has happened is awful, but understanding some context does make it easier to see how France can seemingly produce so many attackers.\n\nFurthermore, anything that we hear about the attacks tonight is just speculation at this point. We don't know anything, so let's not rush to vilify anyone yet.",
"Imagine Bernie Sanders in charge of the US government, it's borders and welfare system over the next 40 years.\n\nSocialism / Liberalism does not work.\n\nHumanity is too immature.",
"Most signs point to the Islamic State of Iraq and the Levant (ISIS) being behind the most recent attacks, but I don't know if they have formally claimed them yet.\n\nTheir long term goals, according to a statement from a spokesman, Abu Mohammad al-Adnani, which was translated into English by _URL_0_ in March 2015 include: \"...with Allah's help [we] want Paris, before Rome and Islamic Iberia and after we blow up the White House, Big Ben, and the Eiffel Tower before Paris, and Rome... We want Kabul, Karachi, Riyadh, Tehran, Baghdad, Damascus, Jerusalem, and Cairo, Sana'a, Doha, Abu Dhabi, and Amman. The Muslims will return to power, to be the vanguard and lead in every place.\" \n\nThey want to build a Sunni Islamic State which would be led by a religious leader they believe to be next in line from the Prophet Muhammad.\n\nParis was targeted in the first attack in early 2015 because of the Charlie Hebdo cartoons, and Charlie Hebdo is based in Paris so they attacked their office there. It was believed to be an act of jihad, which boils down to attacking in the name of their faith, and they found Jihadist flags in the attackers abandoned getaway car.\n\nWe don't have any known motive for this second attack yet, but it's probably jihad again. Paris is a target because it is the capital of France, which has a long history with the countries in the region the Islamic State is active in. So attacking the capital basically hits the country where it hurts most.\n\nIn my view, they're attacking Paris because, well... they hate France. I honestly think it's that simple. These guys are extremists, and their top target is France because of history and modern day relations between France and Muslims. The things that happened under old colonial rule have not been forgotten by new generations. The effects of their former rule over these countries still last politically and socially. They hold a grudge, and view France as an enemy to Islam, so France is a big target. The religious context is huge, they have declared war on France who they see as an enemy to their religon. It's important to remember that these are extremists, and not your every day Muslim. They are ready to fight, kill and die.\n\nFrom the first World War to the present, a lot has happened between France and countries in the area the Islamic State operates in. I think that all plays into this. The old generations overlap into the new ones. They pass down beliefs and history. And here we are today, in a time where extremism seems to be at an all time high, communication is easier than ever, and the instability of key countries is giving rise to leadership that seek their ideal Islamic State.\n\nSo why did they attack Paris? Because they view France as an opponent to Islam and their culture. France's history of foreign relations with these countries is pretty ugly. The new generation of extremists use all of that as motivation and vindication."
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"https://en.wikipedia.org/wiki/Terrorism_in_the_United_States#Attacks_by_date",
"https://www.washingtonpost.com/world/europe/french-muslims-caught-between-rising-islamophobia-and-growing-extremism/2015/03/22/7359329c-c739-11e4-bea5-b893e7ac3fb3_story.html",
"http://journalistsresource.org/studies/international/conflicts/france-muslims-terrorism-and-challenges-of-integration-research-roundup",
"http://www.insee.fr/fr/themes/tableau.asp?reg_id=0&ref_id=NATnon03346",
"https://news.vice.com/article/france-is-sending-more-troops-to-help-iraq-fight-the-islamic-state",
"http://www.aljazeera.com/news/europe/2015/01/qa-marine-le-pen-france-islam-2015113123524709520.html",
"http://www.pbs.org/wgbh/pages/frontline/shows/muslims/etc/faqs.html",
"http://www.lemonde.fr/proche-orient/article/2015/09/27/la-france-a-mene-ses-premieres-frappes-en-syrie_4773677_3218.html",
"https://en.wikipedia.org/wiki/List_of_terrorist_incidents_in_France"
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5bsfm0 | how the targets are decided and who is doing what in case of ww nuclear war | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5bsfm0/eli5_how_the_targets_are_decided_and_who_is_doing/ | {
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"Targets fall roughly into 3 categories: military Infrastructure and people. The majority of nuclear weapons would be directed against enemy military targets such as bases and likely nuclear launch sites to slow down an enemy exploiting the nuclear strikes and invading someone. \n\n\nNext is infrastructure. So roads, railways, fuel refineries etc. Basically make it hard for the enemy to keep their army moving and fighting. \n\n\nFinally some weapons are pointed at major population centres. This is mostly as deterrence. You generally don't want to get your people killed as the leader of said people. If only because that's where your wealth is. \n\n\nAs for who is doing what: \n\n\nThe missile silos are manned 24/7. Someone is there waiting for orders to launch. The air force will begin to put aircraft into the sky in preparation for invasion and maybe to shoot down one or two incoming missiles. They will also load bombers with more conventional nuclear weapons in case they are ordered to go drop them somewhere. The nuclear ballistic missile submarines dive and disappear and come up every so often to listen for orders to launch their nuclear weapons. The rest of the military is essentially going to high alert in case of invasion and to assist in the fallout of the attack. \n\nThe government and high military command goes to secure locations in order to give orders and direct everything going on. There is a very long established chain of command so that whoever doesn't make it is replaced by someone. All the commanders of various military units also have orders in case there are no orders so they will still be doing something."
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3y9r38 | where are we at with the turing test? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3y9r38/eli5_where_are_we_at_with_the_turing_test/ | {
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"It was announced in 2014 that a chatbot posing as a 13 year old Ukrainian named Eugene Goostman had passed the Turing test. While the needed number of judges did vote for this bot, it is not what is popularly defined as artificial intelligence.\n\n They also came under criticism for their use of the 13 year old non-english speaking personality, because was possibly more leniency in judging for the language barrier (and for the mental age of 13) than if the program was communicating fluently in the testers native language."
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||
1bsnjx | unix epoch time | So, I was figuring out the 'date' command in Linux the other day, and came across the subject of Unix Epoch Time. I know it began January 1, 1970, but other than that I have no idea why it is relevant today, or how it may still be used, or why it was started. Here's to hoping someone in computer science can explain it like I'm five!
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1bsnjx/eli5_unix_epoch_time/ | {
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"It's just the number of seconds since 1 January 1970, UTC. Note that the 'UTC' means it is independent of time zone, and your computer takes that into account when it has to show the date, like this:\n\n $ TZ=EST date\n Sat Apr 6 09:11:15 EST 2013\n\n $ TZ=UTC date\n Sat Apr 6 14:11:19 UTC 2013\n\nBut it's all driven off the same epoch time, which increases, one second at a time. It's used everywhere, and is a convenient way to represent time, to one second resolution.\n\nImagine if you tracked your age as number of days since birth. You would then say that you were, say, 7300 days old, instead of 20 years. But if you had to figure out your age 1200 days ago, you just say 6100, instead of, um, wait, no, um ... 16 and something?\n\nCounting time monotonically like that makes math easier. But humans prefer formats like \"Sat Apr 6\". So the computer uses the most convenient format for it, which is number of seconds.",
"Fun fact: In a few years (in 2038 if I recall correctly), 32-bit signed unix timestamps will overflow and become negative, breaking this system. The maximum value of a 32-bit signed int is 2^(32-1) - 1. After that, it wraps around to -(2^(32-1)).\n\nELI5 version: After too many seconds have elapsed, some computers won't be able to handle these timestamps the same way anymore, because they will have increased so much they can't be stored in the same fixed amount of memory. 32 bit computers will be confused and not know the correct date, but 64 bit computers will continue to function normally.\n\n\nedit: for more info see _URL_0_",
"When they were developing Unix, they decided that the internal time counter should just be an integer that tracks seconds from a certain point. Unix started in 1970 so Jan 1 seemed like as good of a time as any.\n\nUnix has spread far and wide and it's clones & derivatives are everywhere. Time hasn't really changed much - most systems have moved to 64-bit instead of 32-bit counters & many support fractional seconds of accuracy. You'll find it in databases and programming languages of all sorts.\n\nIt's a very convenient format to work with - it's just a number. You can easily add and subtract to it. You don't need to use any fancy data structures. It, usually, just works the way you expect it. When dealing with time, simple is good - because there are a great many fine details to take into account (time zones, leap years, leap seconds....)."
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2utz5m | from a skeptics standpoint, how do psychics/mediums/clairvoyants go about getting the conclusions that they come to. | I understand about focusing on generalizations that are basically true for anone but if someone could take me through the process of giving readings and the like, I would appreciate it. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2utz5m/eli5from_a_skeptics_standpoint_how_do/ | {
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"Generalized statements, cold reading, eavesdropping. Those seem to be the primary methods.\n\nGeneral statements: \"Does anyone in this room [of 100+ attendees] have a lost loved one named John? He wants you to let go and be happy.\"\n\nCold reading: _URL_0_\n\nEavesdropping: the \"psychic\" sends a patsy to listen into idle conversations before the psychic comes in. The patsy overhears or even draws out information from the mark, then passes it unobtrusively to the \"psychic.\" The \"psychic\" then knows what the mark wants to hear."
]
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"https://en.wikipedia.org/wiki/Cold_reading"
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3aic3m | why do we see our reflection in windows? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3aic3m/eli5_why_do_we_see_our_reflection_in_windows/ | {
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"The same reason you see your reflection in anything other smooth surfaces eg mirrors/polished metal. Perfectly smooth surface means that light bounces off it at exactly the same angle at which it hits it. \n\nReflections are fainter in glass because most of the light passes through it, only a small amount gets reflected. "
]
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||
5xy82f | how do we know when our sun will go supernova? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5xy82f/eli5_how_do_we_know_when_our_sun_will_go_supernova/ | {
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"Our sun will not go supernova, and when our sun begins to die, it will go big and red.\n\nWe know this due to calculations that we do and observations. ",
"Our sun doesn't have enough mass for that. It will eventually swell into a red giant and eventually putter out into a dwarf. Unfortunately no massive explosions involved. ",
"We know the Sun *won't* go supernova because it isn't big enough. So that makes it easy to say when: Never. You can't get a stick of dynamite out of a cap gun."
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feayx0 | why sound is not flipped (or reversed/messed up in a way) no matter how you flip/turn the source? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/feayx0/eli5_why_sound_is_not_flipped_or_reversedmessed/ | {
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"Sound is vibration in a medium (mostly air). It doesnt matter how the thing creating the vibrations is oriented as long as the pattern/intensity/frequency of the vibration doesnt change.",
"Sound is the vibrations of air in the form of a wave. It doesn't have an orientation. It's a little like throwing a rock into a calm lake - the wave goes in every direction equally. It doesn't matter where the rock is thrown from, or the orientation of the rock. \n\nHowever sound *is* messed up if the source is travelling at speed. That's why the sound of an ambulance changes as it goes past you. When it's approaching you the waves are compacted, and when it's going away from you they're spread out. It's called the Doppler Effect.",
"Sound is a pressure wave in air (or other substance). If the air pressure goes up and down there isn't really an orientation to that event.\n\nThe common depiction of sound as a wavy line is more of a chart or graph of the change in air pressure over time, it isn't like a real vertical or horizontal line is flying through the air into your ear. If you look at the membrane of a speaker moving then you can see that it is if anything a forward and backwards movement, and the eardrum moves in a similar fashion.",
"Actually it is, and you can hear it.\n\nA common trick in large concert sound systems is to flip one subwoofer backwards, creating a '[cardioid array](_URL_0_)' with the goal being to cancel out the sound waves going to towards the stage (or the rear of the array).\n\nThere is a reason why you see all the speakers pointing towards the crowd at a concert.",
"Sound is a wave or series of them, you're thinking of it as having an up and down property, like the top of the wave being different from the bottom of the wave. That's not the case, the wave is constant in itself, what makes different sounds is the size of that wave and the frequency at that the waves are coming, in a simplistic way."
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aycxl2 | how do you tell if something is an actual rock and not something made by man? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/aycxl2/eli5_how_do_you_tell_if_something_is_an_actual/ | {
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"There is no simple, straightforward method of doing so. There are some general rules of thumb we can use, but for each of those you will find at least a few exceptions. In general, you don't see right angles in nature, but bismuth crystals will display them.\n\nThe best answer I can give is that geology is a science that you would have to spend an entire life studying to fully appreciate, and geologists have a wealth of different information that they can use to try to figure out if a particular substance is naturally formed.",
"It’s kinda difficult to manufacture an aggregate of minerals and stick them together to look like a rock. Any efforts just wouldn’t look....natural. Nature either takes a long time to make rock, or it has access to means that we don’t (or both). For example, the rock that makes up the seafloor is erupted at [mid-ocean ridges](_URL_0_) and so forms relatively quickly just from lava cooling down underwater, but it’s made from partial melts of the mantle, which we don’t have access to. Even if we managed to take some mantle rock (occasionally small pieces are transported to the surface in volcanoes) then it would be hard to replicate all the little inconsistent things in the way natural rocks are generated. There will always be impurities and what have you in natural rock. \n\nMaybe if someone didn’t know what concrete was then it could pass as a weird looking sedimentary conglomerate. Industrial slag is often mistaken by non-geologists for natural rock, often in the hopes that they’ve found a meteorite. There are always tell tale giveaways when a rock is not natural though. It’s difficult to explain what all of them are without examples in front of us to go through while actually holding them and looking at them from different angles, being able to test the density and hardness etc. They say the best geologist is the one who has seen the most rocks - there’s definitely something to that idea. ",
"There's no single answer to this because it really depends what specific example we're talking about. The most common material we see misidentified as rocks on /r/geology is slag, which is relatively straightforward to identify if you know what you're looking for and it looks fairly distinct from rocks you will naturally find in nature. \n\nIt can, however, be much more difficult, since it's possible to grow minerals synthetically that mimic the natural processes that form them, to the extent that it's extremely difficult to distinguish the artificial product from a natural example, physically (and potentially even chemically). For instance, experimental petrologists will create artificial rocks in special furnaces which can be essentially impossible to distinguish from a natural rock."
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2633l4 | when sucking a piece of candy (hard or soft) why do you have the urge to crunch and swallow it instead of savoring the flavor longer? | Every time I go to the barber shop I get a sucker and inevitably wind up crunching the hard candy off the stick and eating it instead of fully sucking it and dwindling it down. I do this with Mentos as well. Seems like it would be better to keep sucking the one piece of candy and letting it last longer, but I always have the urge to just crunch and eat it. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2633l4/eli5_when_sucking_a_piece_of_candy_hard_or_soft/ | {
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"Because your whole life youve been crushing things with your teeth and swallowing them immediately as they enter your mouth. It becomes a reflex.",
"i think it has to do with the same reason why when you toss a dog a piece of food they pretty much inhale it. while humans enjoy flavor i think we have a more basic instinct of \"that was some food eat more right NOW\" your body is less concerned with enjoying food as it is with consuming as much as possible. if you go back to the kill or be killed stage of are evolution it would make total sense to cram as much food into yourself as soon as possible before it went away.",
"I am interested as to why gum does not give the urge as described. Is it pure fear that swallowing gum \"gets stuck in your stomach for 7 years\"(which is BS)? Every time I even think about swallowing a strip of Orbit, I seem to just say no to myself, but as the OP suggests, for every other food we have the urge.",
"It's forbidden and some people like danger. ",
"Must be a person to person thing, i prefer to let it melt away in my mouth and savor it all."
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383c5b | how is it possible that i always lose at blackjack, despite playing the exact same rules of hit/stay as the dealer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/383c5b/eli5_how_is_it_possible_that_i_always_lose_at/ | {
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"The biggest reason is just that the dealer plays last. If you bust, the house still wins your bet even if the dealer busts against someone else at the table. That advantage is bigger than any of the rules in your favor (being able to split, 3:2 payout on blackjacks, dealer must stand on hard 17) since he only has to worry about busting on hands where you stay under 21.",
"It's actually a bad idea to play the same rules as the dealer. This is because you aren't taking advantage of bust cards (3 4 5 6). You shouldn't hit if the dealer is showing those cards because there is a good chance the dealer is going to bust."
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1jbxjj | why are hospital emergency signs always red? | I've looked this up on google, and all I get is a bunch of pictures of emergency signs instead. I've noticed that every hospital that I've seen, even ones in Mexico, they all have a big red sign on the hospital and the direction list saying 'EMERGENCY' in big lettering and everything.
Edit: okay, I get that they're easy to see and some other countries may have different colors but I'm asking why do they particularly associate the color red to the word "emergency", like even "ambulance entrance" is in red and shouldn't the paramedics already know where to go anyways? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jbxjj/eli5_why_are_hospital_emergency_signs_always_red/ | {
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"Big bold red lettering is the easiest to see both during the day and at night.",
"The simple answer is that it's a standard. Sometimes standards don't necessarily have a specific reason for why they're one way and not another way, but the most important thing is that they're consistent so people can know what to expect no matter where they are.\n\nRed is an eye-catching color and is used for many emergency purposes. It makes sense that it be used for emergency room signage. I've never built a full-fledged hospital (and I'm on mobile right now) so I'm not sure where you can find hospital standards, but I'd bet money that there is a specific national standard for hospital signage including colors, language, size, and placement, and that those standards are adopted into state and local building codes nationwide. They may even be part of ADA (Americans with Disabilities Act) regulations."
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3coazh | why do people pass out within a few seconds at high altitude (e.g. loss of cabin pressure) but we can hold our breath without passing out for much longer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3coazh/eli5_why_do_people_pass_out_within_a_few_seconds/ | {
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"If I tell you to hold your breath, straight away you'll take a really deep breath so you get a good lungfull of air to go on.\n\nIf you're in an aircraft that suddenly loses cabin pressure without warning, you don't get the opportunity to go from normal breathing to preparing to hold it. You'll breathe out as normal, and then your next breath in will be ineffective because you just can't get the oxygen you need."
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1tihfj | why is cosmetics testing on animals always so abusive? i don't see why make-up requires torturing monkeys, mice, etc | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tihfj/eli5_why_is_cosmetics_testing_on_animals_always/ | {
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"text": [
"Because makeup isn't always used for its perfect, intended purpose. Poisonous lipstick might not be such a big deal when used normally, but when someone's toddler eats it? That's a problem. They need to test every scenario to ensure that their products are safe.",
"In order to release a product like cosmetics to market, you need to figure out how much of it will cause irritation to the skin, and how much of it ingested will cause death. \n\nFor death, you're looking at what is called the LD50. The LD is Lethal Dose and the 50 is 50%. I.e. what dosage, when administered to a large population, would kill half of them. \n\nOne way to determine this is get a population of test animals and dose them, and then keep increasing the dose until half of them are dead. It doesn't matter that some might get sick and be in pain, you have to keep going until half are actually dead. So basically there is no permissible outcome from the test other than half the animals dying what is most likely a torturous death. Even if you dose them a hundred times higher than what could be possible from normal use, you can't stop. You have to find out what the LD50 is. \n\nAt least that's what has traditionally been the case. Regulations are changing now so that if you can show that it isn't possible to cause death from realistically possible dosage, that's enough. \n\nSimilar sort of thing for irritation - you need to figure out how much will cause severe irritation. Not just whether a regular use will cause irritation or not. So you have to keep going until the poor animals are in severe pain. And then you kill them anyway. "
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16fixc | why is wearing fur considered less moral than eating meat? | Considering that eating meat is not *really* necessary for survival nowadays. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16fixc/eli5_why_is_wearing_fur_considered_less_moral/ | {
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"I believe because it's because it's so wasteful. Slaughtering a cow can feed dozens of people, killing a chicken can feed a couple.\n\nYou have to kill something like 40 baby foxes to make a fur coat, and the meat is just disposed of. \n\nWhile you can make the argument that meant isn't *really* necessary for survival it's very difficult to say what IS necessary. How much can you chip away? And while it's arguable meat is one of the best foods for humans. ",
"Well one keeps you alive, and the other is solely for decoration. It's not hard to see a distinction where one would be morally acceptable to most people and the other would not. There's even the argument that a *purely* plant-based diet is not quite as healthy as one with *some* meat in it, so you could even claim that eating meat is *necessary* for optimum health.",
"Most of the furs that are worn are from animals that people don't eat, like fox and chinchilla. Not many people have the same problem with wearing leather because we still eat cows. \n\nThe one exception would be rabbit, which does tend to be eaten and worn.",
"It's easier for people from developed nations to say \"eating meat is not necessary for survival these days\"; In many parts of the world you don't have the option to be picky about what is on your plate. \n\nThat being said, there is no such thing as a \"kind method\" when it comes to raising and then killing animals for their fur. The methods used are barbaric and awful, and often times the animals are subjected to being skinned alive. Their deaths are never quick. It's the pain involved in procuring what is a *luxury* item that creates a stigma around fur wearers (deservedly so). \n\nHowever, please remember this is also a regional thing. In other parts of the world, people wear furs as a means to stay warm, and to literally survive harsh, frigid winters. \n\nFor the record, I'm a vegan, if that makes any difference. But I learned a long time ago that it's useless to try and subject your views on others, especially when often times there are factors involved that all too often are not taken into consideration. ",
"But the alternative to fur is chemically cooked up plastic materials , polyesters and such, which are far worse to the enviroment than killing a bunch of fluffy animals. \n\nYou are doing much more evil be wearing a polyester jacket, than by wearing a fur.",
"Animals killed for their fur are often killed only for the fur which means the rest of the animal is wasted; thrown out or fed to other animals. Animals consumed for meat are killed for the meat, everything else (hooves, skin, etc) can be used. Not a lot of wasted on a commercially butchered animal. ",
"because people don't think about where meat or leather come from, but fur looks like its source. "
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1pypkp | why is it widely believed that o. j. simpson is guilty, even after being acquitted by a jury? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pypkp/eli5_why_is_it_widely_believed_that_o_j_simpson/ | {
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"The preponderance of circumstantial evidence and motive on his part versus lack of evidence or motive for a phantom killer.",
"[His book makes a compelling case](_URL_0_).",
"In the U.S. justice system, there is a difference between being innocent (i.e. \"I did not commit the crime\") and not guilty (i.e. \"You cannot prove I committed the crime.\")\n\nWhen you go to court, the judge gives you the choice of plea: guilty, not guilty, and a few others that I won't go into. But these are the main two.\n\nSince Simpson said he was \"not guilty\", the prosecution has to convince 12 people that he indeed committed a crime and he should be held criminally liable for that crime. Both the prosecution and the defense have a set a rules but the rules are more strict for the prosecution.\n\nThe prosecution, in this case, did not follow proper evidence procedures, contaminating the evidence. There are a number of other things but this was the main one.\n\nBecause this evidence was never heard by the jury, they acquitted Simpson.\n\nThe rules of evidence are there to protect the judicial process. While there was some argument that the police planted evidence, chain of custody was broken so it could not be used.\n\nPlease note that the defense does not have to prove that the police actually planted evidence. They used the fact that the chain of custody was broken to supplant this idea.\n\nSo, people being trusting of the police, and given Simpson's record of violence /u/flipmode_squad [pointed out](_URL_0_), most people believe he should have been found guilty.\n\nBut lack of evidence means that Simpson would be acquitted.\n\nTL;DR: The rules of evidence must be followed in order to convict someone of a crime. Lacking said evidence, the jury must acquit.",
"It should be noted that OJ Simpson is in jail right now. He and some accomplices robbed a sports memorabilia dealer of what he claimed was his own property at gunpoint (which is totally insane). His trial was not nearly as widely publicized as the murder trial. He was sentenced to 33 years in jail, and isn't eligible for parole for another four years. \n\nIt's entirely possible that he may die in prison, and some people think that's perfectly fine.",
"He was found guilty in civil court, however civil court has a much lower threshold for verdicts against.\n\n\nThere is also a theory that he was acquitted for political reasons -- LA didn't want another round of Rodney King riots.",
"He was acquitted **in a court of law** meaning while on trial he also enjoyed all the protections the law gave him such as fair trial and the burden of proof laying on the prosecutor. So while there was a wealth of *circumstantial* evidence that would point in his direction, there was not enough concrete hard evidence implying or showing it was murder on his part and technically a jury cannot find someone guilty unless there is enough evidence to \"prove beyond a reasonable doubt\". Circumstantial evidence may be used to make deductions everyday in the real world but definitely isn't enough for a trial in a court of law. But again, the circumstantial evidence does not work in his favor for his reputation. \n\nIt's like if there are two boys and a cookie goes missing. The mom finds an empty glass of milk in the boy's room who was complaining of being \nhungry but finds no crumbs or used napkins of the cookies. She may really want to believe the boy stole the cookie or \"know\" it but she can't prove it because there's no real evidence and therefore reasonable doubt. Also the other boy could have done it. "
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3bpqjf | how is it that the us women's soccer team is the one of the best in the sport worldwide, yet the us men's team is lackluster in comparison? | Seriously, the US women's soccer team has been amazing for a long time and the US-Germany match today was fucking riveting. And now it's just a match against England or Japan to win the cup. Why doesn't that talent+teamwork match with the US men's equivalent? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3bpqjf/eli5_how_is_it_that_the_us_womens_soccer_team_is/ | {
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"text": [
"Most of the best male American athletes choose to play sports other than Soccer. Women's soccer is a top dog sport by comparison and attracts some of the best athletes. "
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44uwco | how is neutron star matter so dense that a teaspoon of it weighs 10 million tons? | Everything that has mass takes up space, so how can that many neutrons fit in such a small area to weigh so much? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/44uwco/eli5_how_is_neutron_star_matter_so_dense_that_a/ | {
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"A hydrogen atom is 99.9999999999996% empty space. If you can collapse that space into a plasma of subatomic particles without atomic structure, you can see how much opportunity there is to increase the density.",
"It's because there's more stuff in the space than there usually is. Ordinary matter is made up of atoms. An atom has a very, very, very dense nucleus at the center, and then a cloud of electrons around it. If an atom were the size of a football stadium the nucleus would be a pea at the 50 yard line. Nonetheless, the nucleus has almost all of the mass of the atom. (Practically 100% of the mass. Electrons weigh almost nothing.) \n\nAtoms tend to stay a certain distance from each other and not overlap because the electrons repel each other and keep them that way. You don't fall through the floor because the electrons in the atoms of your feet (or shoes) repel the electrons in the atoms of the floor. (There's a subtlety here related to something called the \"Pauli exclusion principle\" that I'm not going to go into. Suffice it to say that this isn't really the same thing as the \"like charges repel\" you learned in highschool physics.) \n\nIf someone pushed down on you hard enough though, you'd break through the floor. That's sort of what's happened to a neutron star. Healthy, normal stars are in balance. The nuclear explosions in the middle try to push the material of the star away, and the gravity of the star tries to pull everything in. Eventually the nuclear fuel runs out. But the gravity remains. So the whole star starts falling in towards the center of the star. There are some different options as to what can happen: \n\n1. The atoms get packed in as much as they can before the electrons pushing each other away stop the falling. This gives you a \"white dwarf star\". \n\n2. The star is too heavy for that, so it keeps falling, and the atoms \"break\". The electrons hit the nucleus, where they combine with protons to form neutrons. Eventually the neutrons will start to push each other away and the star stabilizes at that smaller size. This gives you a \"neutron star\". \n\n3. Nothing ever stops the material of the star from falling. Everything falls to the very center of the star and occupies the same point of space. This gives you a \"black hole\". This is the weirdest option. \n\nIn option 2, remember how most of normal atoms are empty space. Now you just have neutrons basically sitting on top of each other. The whole stadium is full of peas, in the analogy. That's why it's so dense. The 99.99999% empty space of normal atoms is all nothing but super dense nuclear matter. \n\nAlso, if you actually *had* a teaspoon of neutron star it wouldn't *stay* that dense. It's only that dense because the gravity of the star is *holding it* that way. If you somehow managed to separate a teaspoon from the star it would just explode back out the neutrons would dissolve back into protons and electrons. (This would certainly kill you if you were holding the teaspoon.) It can only be that dense in that very strange high gravity environment. ",
"For fun I looked up what a cubic meter of uranium weighs (because its heavy). It's about 19 tonnes.\n\nI think I askedReddit and got an answer for how big that cubic meter of uranium would be if you took out all the empty space in the atoms. My answer was a cube smaller than the width of a human hair. About a trillion times smaller (if I remember correctly).\n\nSo I worked out what a cubic meter of Uranium with all the space taken out, would weigh and got 19 trillion tons.\n\nCrazy. So I imagine even at a million tons per teaspoon, there is probably still a lot of space between the atoms.\n\nIf I'm wrong, I'm happy for someone to tell me.",
"A neutron star is essentially the neucleus of a giant atom. The density is about that of the neucleus, so even a tiny amount is incredibly heavy.\n\nDid a physics problem where the average density of a neutron star, and the density of a neutron were related. Was something like 95% the density."
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2rsp2p | if the affordable care act requires that people with pre-existing conditions can not be denied by private insurers, why wouldn't everyone just wait until they were sick and then purchase insurance? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2rsp2p/eli5_if_the_affordable_care_act_requires_that/ | {
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"Theoretically, much of this is combated by having open enrollment periods. ",
"Because the ACA has provision that penalizes anyone who doesn't have insurance. For 2015 the you'll pay the *higher* between 2% of your income or $325 per person for the year. So the idea is people can pay the IRS for no insurance or pay to get insurance. ",
"You can only apply for insurance during \"open enrollment periods\" (the 2015 one ends February 15th) or under certain specific circumstances called \"qualifying life events\" (get married, be born, change jobs, things that might require you to change health insurance basically). If it's not an open enrollment period, and you aren't undergoing a qualifying life event, then you can't sign up for insurance and are out of luck if you get sick.",
"This is why _URL_0_ has enrollment periods where if you don't sign up in that period: you are SOL if you do get sick because sign ups are closed.\n\nYeah, if you do get sick during enrollment you could get insurance but that's a big bet to make.",
"That is one of the many fallacies in the ACA. It is partially addressed by penalizing you for not having insurance, but in many if not most cases, it is cheaper to pay the fine than buy the insurance.\n\nOf course, when someone develops a condition where he/she needs insurance, the insurance companies must cover that person and condition and pass the cost on to every person receiving their insurance coverage.\n\nPrior to the ACA, the States provided insurance for otherwise uninsurable people. The cost of care did not raise insurance cost for everyone. But those plans went away when the ACA was passed.",
"You noticed that, \"loop hole\" did you. So did the government. That is why the law enacts individual mandates, employer mandates, and IRS enforced taxes, (once upon a time referred to as a fine) for non-compliance. "
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3nzub7 | why didnt i get withdrawals from quitting smoking | was a chain smoker for 9 years. quit cold turkey without any withdrawals. how is this possible ? before i wanted to quit, going 2 hours without a cigarette was impossible without feeling irritable and grumpy
EDIT: 26 days since last ciggy | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3nzub7/eli5_why_didnt_i_get_withdrawals_from_quitting/ | {
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"How long has it been since you quit?"
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10fc2u | the reddit front-page algorithm | Please explain to me how upvotes, downvotes, points, and how long ago something was posted (and maybe some other factors) come together to decide what posts makes it on my front page. Thanks. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/10fc2u/eli5_the_reddit_frontpage_algorithm/ | {
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"Totally stealing this from a bestof post about the algorithm. I couldn't find it so I am typing this out. \n\nThink of reddit like a horse race where each post is a horse that enters the race at the moment it is submitted. The number of upvotes it receives is like giving it energy boosts which makes it run faster. More upvotes means more boosts which makes the horse (the post) run faster. So at a moment of time (maybe every time the page is refreshed) the front page is a snapshot of the top 25 horses (I think the front page has 25 posts...not sure). Over time, new posts are submitted with the default boost i.e new horses enter the race with some default speed. But remember that there are horses that have already been running very fast (due to all the energy boosts). These very fast horses overtake the new horses in real time. Thus you don't see only new posts on the front page but only those which have considerable momentum (upvotes). Overtime, a new horse will get lots of boosts and manage to be in the top 25.\n\nIn this analogy, a bad post is a horse that is beaten to death (much like all memes here)! :)"
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32ybgj | why drawing picture of allah is not allowed in islam? | Allah(or god) is someone who created everything, from small insects, trees to planets , sun and the universe.
Why then is drawing a picture of Allah banned in Islam?
Is he so weak that he gets offended when some tries to draw him? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32ybgj/eli5why_drawing_picture_of_allah_is_not_allowed/ | {
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"They aren't allowed to draw Muhammad. No one will every try to draw Allah because as an omnipresent deity, it has no form we would recognize.",
"I'm not muslim but if you wanted a serious and accurate answer to this question you wouldn't suggest their prophet who they are clearly find of, is weak. ",
"Because Allah is an ideology and to depict Allah as a physical feature would seem to *cheapen* the notion of what Allah represents.",
"To clarify, it is a Sunni Islam custom to forbid religious depictions... and to clarify further, it is only an extremist group of Sunnis who follow that custom. The Quran (just like the Bible) forbids idolatry. Over the centuries, some ultra-conservative interpretations of that law determined that any depiction is a form of idolatry. The actual hadith (which is a separate collection of Muslim texts than the Quran) forbids ALL drawings of any sort... \"Verily the most grievously tormented people amongst the denizens [inhabitants] of Hell on the Day of Resurrection would be the painters of pictures\"",
"Not exactly explain like I'm 5 but more explain like you're Christian or Jewish: \n\nIn the Christian bible (and Jewish Torah) one of the commandments, the 2nd (or 1st depending on the translation) says something to the effect \"Thou shalt not make unto thee any graven image\" the translation varies. But one interpretation of this is no false idols, but another interpretation could mean don't make an image that you would worship. Under the later interpretation, a crucifix of Jesus that people pray to is problematic, because depending on how you look at it, are they praying to Jesus or are they praying to that image of Jesus.\n\nA lot of the rules of Islam seem to come from problems they saw with early Christianity. One rule is that the Koran cannot be translated out of Arabic, possibly because they saw problems with the Christians arguing over translations of the bible. Similarly they may have seen Christians praising idols of their Jesus and found it hypocritical in the context of the 2nd commandment. It may have been a well intentioned rule to not make images of people in general as those images might be worshipped and take attention away from actually praising their God. "
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2yyt96 | why do arabic men grow such mean beards while they live in hot climates? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yyt96/eli5_why_do_arabic_men_grow_such_mean_beards/ | {
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"It's mandated by Islamic dogma, two aspects in particular:\n\n1. In the hadeeth of Zayd ibn Arqam Mohammed said: “Whoever does not remove any of his moustache is not one of us \n\n2. God's command for Abraham to keep his beard.",
"God gave Abraham some mandates regarding grooming, including to keep his beard, cut his stache, trim his nails, and shave his pubes and armpits. The beard is the most obvious one to notice of course and the most out of the ordinary."
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33mms2 | how do our ears position the source of a sound in 3d-space when the sound is behind us? | I can completely understand spatial positioning when the source of the sound is within ~120^o in either direction, but beyond that, how does it work? Like, how do we determine that the sound coming from the rear speakers in our home theater is supposed to mimic/emulate a sound behind us? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/33mms2/eli5_how_do_our_ears_position_the_source_of_a/ | {
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"Accuracy of hearing is not 100% precise. If the distance to the sound is similar from both ears you may confuse the direction.\n\nThink about crickets in the grass, one cricket can appear emmiting sounds from different directions. By moving your head you can narrow down the location of the sound. If you will sit absolutely still and two people will emit sounds with the same echoes standing in front of you and behind you, you will not be able to tell the exact location."
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1ohids | why do material things i buy seem extremely expensive when i buy food for the same money and not give a second thought? | Also, I tend to have a much harder time buying things in person than when buying things online. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ohids/eli5_why_do_material_things_i_buy_seem_extremely/ | {
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"Well its because you need to eat, but do you need a new iphone?",
"There have been studies on this phenomenon. The virtual shopping doesn't feel as real and therefor you don't think of your money as real because you're not using paper money and counting it out, you're not dealing with a store clerk or hard goods, everything is virtual. Things being less real makes it much easier to buy things and spend money you normally wouldn't.\n\nRestaurant service is designed so that you eat and drink without as much awareness of the cost until you have finished and bought everything already. The final cost is hidden from you until the very end, and then you are still expected to tip. It's another instance where the cost is hidden from you and reality doesn't settle in until after you've already done it. \n\nRetail feels immediate, dining and internet shopping do not feel immediate because the bill arrives after the fact."
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5vclso | why do racing cars have so many sponsors - what's the point or benefit to the companies? | I'm trying to understand this, even though cynical part of me says "tax writeoff". Why do racing cars have so many sponsorship decals on them. You might say "it's a great promotion if the car has T-Mobile livery" - that's fine, but what's with dozens and dozens small, almost invisible stickers and logos plastered all over the car.
Do people really see some miniscule bumper logotype on a photograph and think "wow I should google these guys".
Please explain. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5vclso/eli5_why_do_racing_cars_have_so_many_sponsors/ | {
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"It's not about the viewers immediately Googling the name. It's about getting viewers subliminally exposed to the name over and over.\n\nIt's the same reason they play the same commercial sometimes multiple times an hour, so the first thing you think about when you want oil is \"Valvoline\".",
"The sticker on the car is less important than purchasing the right to call themselves an official sponsor, which they can then do in their own promotional material. ",
"Car racing is a very expensive sport to compete in. Consider the list of things a racing team needs to have to compete: Race Spec Cars, Drivers, Parts, Mechanics, Tires, Track Times to practice on, and so on. Even if you win the race it's a high bill to pay for. Even at smaller race series this isn't cheap. All those sponsors help make racing a sport that people can afford to be in.",
"It's branding... in addition to having your logo seen on the cars during a race, there are also additional benefits that come from sponsoring a race team, such as having those drivers in ads for you, being able to promote giveaways/sweepstakes featuring the race team, etc. Many race fans are very loyal to those who sponsor their sport and favorite race team/driver so they will seek out who is sponsoring them.\n\nAs for tax write-offs, that's not a business practice for making such a decision... while spending $1 million on a sponsorship would be an expense that would reduce their profits, they spend more money than they save so it's still a net expense.",
"I am a rally driver and I can explain it. There are two things when it comes to sponsorship. First one is branding - it goes well when the livery is easy to recognize and the logos are big. Consumers see a car and if the like it, it makes a positive connection with the brand. You asked: ok - full one brand livery is ok, but what with the small ones, often barely visible. This is second thing. The company that have a logo on a car can use the team, the car or the drivers (it all depends on the contract) for their advertising purpouses, and build positive connection to their product or company. Some minor sponsors of F1 or WRC use whole team as their communication. They can use some part of the car with a logo and say - proud sponsor of XYZ racing/rally team. It works good with specific target groups and it cost much less money than being main sponsor."
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b2en5b | batteries. what's the difference between volts and amps? how does a charger know when a battery is fully charged? | As a specific example, I have a drone that takes 3.7v and 500mAh, but I can use 3.7v and 750mAh batteries for it (from another drone) and it works just fine. Does it fly longer. Another example is that my daughter has one of those electric cars with a 6v 5amp battery in it. I replaced it with a 12v 5amp battery and it goes twice as fast. If I used a 6v *10amp* battery, would it go the same speed but for twice as long? Oh, and if I connect two batteries, what's the difference between connecting them in in line (pos to neg) as opposed to side by side (pos to pos, neg to neg)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b2en5b/eli5_batteries_whats_the_difference_between_volts/ | {
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"mAh (milliamp hour) is a measure of capacity, whereas voltage and amperage are measures of energy flow. Voltage is a function of the battery (think of it as electrical \"pressure\"), amperage is a function of the circuit that it is hooked to (equivalent to how far open the taps are). Hooking up a higher voltage battery to a circuit can be dangerous and cause damage to the electronics, but hooking a battery with the same voltage and higher mAh will just cause the thing to run longer before it exhausts the battery.",
"The amps (mAh or milliamps per hour in this case) are like how much juice the battery can give before it dies. The volts is the level of delivery of that juice. The higher the mAh the longer it can deliver the volts. Hence why you can use a larger mAh battery on the same device. (And it will last longer). If the volts were different it wouldn't be compatible and could even provide too much as to damage the device. ",
"The capacity of the battery is like the capacity of a bucket. If the battery holds 500mA*hr and you drain it out at a rate of 1A, it will last half an hour. The 750mA batteries will last 50% longer under the same load (though they are presumably heavier so the drone has to work harder...).\n\nBe careful with Amps and Amp Hours. They are not the same thing at all. In this case you probably mean 5 AHr and 10 AHr in which case, yes, the 10AHr battery will last twice as long.\n\nOn the other hand, an automotive starting battery has a rating \"cold cranking amps\". This described the maximum current the battery can deliver over a few seconds and *has nothing to do with the size of the battery*. A deep cycle might be quite a bit bigger (and have much more capacity) but it probably can't deliver it is as quickly.\n\nA couple of simple and useful equations:\n\nV = IR.\n\nVoltage (Volts) = Current (Amps) * Resistance (Ohms).\n\nP = IV. \n\nPower (Watts) = Current (Amps) * Voltage (Volts).\n\nThe resistance is determined by the load (the drone or the electric car). So doubling the Voltage without also modifying the car made it twice as powerful. ",
"There are three different, but related quantities you’re asking about when it comes to batteries;\n\n- How ‘strong’ is your battery? Measured in Volts\n\n- How ‘fast’ can your battery go? Measured in Amps (or milliamps for smaller batteries)\n\n- How much total energy does your battery have? This is determined by how long it will last when it goes given a certain speed. We measure that in Amp-Hours or milliamperes-hours (mAh)\n\nBatteries will always push a circuit as hard as they can (use all their Volts). But how fast a circuit goes depends on its resistance. A high resistance circuit will not run as fast (i.e., it uses less Amps).\n\nUsing a battery with the same strength (Voltage) but more or less total energy (mAh) just changes how long a device will run - there isn’t any risk or other effects on its behaviour.\n\nUsing a battery with a different strength (Voltage) can change how a circuit behaves and has some risks of damaging the device.\n\nIn the example of your daughter’s car, we can probably assume it has a fairly simple dc motor circuit in it. When a battery tries to turn a dc motor, how fast it goes is proportional to the strength (Voltage). If you double the voltage, you will double the speed (as you observed) - you also doubled the Amps being drawn from the battery. This means if your 6V and 12V battery both had the same mAh, the 12V would run out of energy twice as fast (because of the faster running circuit (higher Amps)).\n\nSo, the car is more fun, just not for as long...\n\nBut, there is also a risk - running faster with a stronger battery means it’s consuming higher power, and heating up, which might cause the motor to burn out completely. Then the car is no fun at all :-(\n\n",
"Long story short, a charger knows a battery is charged by how much current the circuit has/draws (amps). As the battery charges, the current decreases. A certain level means battery is charged."
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5awxfn | how significant is the cubs winning the world series in the world of baseball? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5awxfn/eli5_how_significant_is_the_cubs_winning_the/ | {
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"The World Series is the championship of the top baseball league in the US/Canada. This top league, Major League Baseball is the oldest major sports league in the US, dating back to 1876 (or some would say 1871). The Cubs along with the Braves are the two franchises that can be traced back to 1876. Of those two, only the Cubs stayed in their original city.\n\nThey haven't won since 1908. Simply put, that's just a very long time. Generations of baseball fans were born and died since the 1908. All this time, despite not winning, the Cubs remained one of the more beloved franchises due to them playing in a big city (Chicago) and in one of the two remaining historical ballparks, Wrigley Field. As recently as the 1980s, there were no lights in Wrigley and all their games needed to be played in the daytime. As old an historic as this ballpark is (buiilt in 1913), the previous championship in 1908 pre-dates that park!\n\nI'm sure if some team or country hadn't won something equivalent over in the UK for 108 years, it would be a big deal when they finally won.",
"I don't know anything about soccer either here or there, but I'll try to fill you in on some baseball. First of all, the Mets are a team so good job :). Second, the World Series isn't the league, it's the championship of our baseball league, the MLB. This \"World Series\" is the championship between the two teams who have won their side of the playoffs bracket (I assume most sports have this same concept). The Cubs winning is significant because they haven't won since 1908, thus ending their 108 year drought. ",
"I don't know the EPL enough to make a proper side by side comparison, but the Cubs have one of the largest fan bases in the USA and had no champions in living memory. Not only do they represent the 3rd largest city, but the channel that airs them (WGN) is nationally broadcast, so a lot of people with no other connection to the city grew up watching them. Sometimes more than their own local team because of MLB's ridiculous blackout rules.\n\n \nSo, you have a team with a massive following, sometimes literally stretching back 3 and 4 generations, who have never seen a win and many who thought they never would. A significant chunk of the United States wasn't even part of the country the last time they won. Back to the Future 2 made a clichéd throw away joke about the Cubs winning the world series *30 years ago*. It was the most celebrated and lamented title drought in American sports, and the only one that even came close were the Boston Red Sox from 1928-2004.",
"MLB = EPL\n\nInstead of a double round robin, the MLB plays 162 games in a season and then the top 10 teams go to the playoffs. The World Series is liking playing the FA Cup final 7 times.\n\nThere's no Relegation/Promotion, so the teams will always be around. In the EPL, there are giants (Arsenal, ManU) and minnows (Burnley, Stoke). While the MLB has has richer teams--the ones on big markets (LA Dodgers, NY Yankees)--the wealth is spread around. This means teams go up and down with how good they are. \n\nThis year, the Cubs were the favorite to win the series at the start of the season. You could probably think of them like Arsenal: they're a strong side who you expect to do well, but it hasn't happened for them recently. Although for the Cubs it was 108 years. "
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26iuct | what is the purpose of terrorist attacks, if they only give the group a bad name? | Unless it's a hostage situation or something, where the terrorists have something to gain, what purpose do they actually serve? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/26iuct/eli5_what_is_the_purpose_of_terrorist_attacks_if/ | {
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"Terrorists attempt to strike fear into their enemies' civilians. If a country suffers terror attacks, the civilians might think to follow what the terrorists want to avoid future attacks.\n",
"Some publicity is better than no publicity. ",
"Apparently Osama bin Laden said that the purpose of his campaign was to destabilise the USA by bankrupting it. He claimed similar tactics brought about the collapse of the Soviet Union in 1980s and early 1990s when they got bogged down in an expensive war in Afghanistan.\n\nIn other arenas, the IRA would claim that their campaign of violence in the 1970s, 1980s and 1990s got them a seat at the negotiating table at the Good Friday peace talks, although they seem to have realised that independence through violent uprising was a lost cause by 1998.\n\nOn the ground, the suicide bombers are likely to be motivated by a mixture of desperation, religious extremism, vengeance and brainwashing. You can't expect much logic there.\n\nA lot of countries have won independence on the back of armed uprisings (e.g. Cuba, Israel, USA). If they are successful, they call themselves liberators. If they are unsuccessful, the winners label them terrorists, so a lot of it is propaganda and semantics.",
"Depends on the group but it's usually punishment for something the person/country did. \n\nSome groups are (in my opinion) wrongly classified as terrorists as they have an actual military objective, are run like a military and use guerrilla warfare. The PIRA would come to mind. ",
"It really depends on what the group is trying to achieve. It could be anything from simply punishing a population for its support of a certain position (ex. County X supporting country Y) or it can be used in an attempt to slowly delegitimize the ruling government. If a government can not protect it's people, people will turn from it and seek those who can (often the people planting bombs).\n\nTerrorism is part of a broad, overarching strategy and it's best not to look too deeply into any one act unless the target has symbolic value.",
"If you can't wage a war on a country because you are out-gunned, and out-manned then you resort to terrorism. With terrorism the idea is to scare civilians of a sovereign nation until the civilians demand something be done, and because it is so hard to fight small terrorist cells, especially abroad, then the idea is that the government will give into the demands of the terrorist group. It might give the terrorist a bad name in the nation they attacked, but back home it could be a message to anyone else who shares the terrorist groups ideologies, and could bring in more support and recruits from home. "
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4u5bq4 | can america actually pull off significant or total economic isolation? | I hear this topic thrown around a lot (especially with the current election cycle), and being a layperson when it comes to economics, I don't have nearly the scope of comprehension required to have an educated opinion on this matter.
Are there any comparatively simple resources that explain whether the U.S. could actually successfully maintain this with its current standard of living? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4u5bq4/eli5_can_america_actually_pull_off_significant_or/ | {
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"Absolutely not. The USA imports and exports A TON. \n\nLong story short, there would be many jobs lost, many companies would go into a panic, and common day goods would not be available.\n\nIt is arguable if the USA has the resources (in our land). But in our interconnected world, countries are really dependent on one another. Perhaps in the future with some sort of new technology this could happen. But not now.\n\nEdit: Also, the USA's culture is built up on the cultures of the world. To separate would mean we would have to form a new identity and new economy (or invade Canada or Mexico and adapt some of their stuff).",
"Do we all want to live like the Amish and work all day just to feed and clothe ourselves? Probably not. \n\nThe US has significant resources, but we can't possibly replace all the things that the world marketplace makes available. For many things where US producers don't currently have an advantage, who would invest to rebuild the infrastructure and skillsets required? To even build that out, you might need other components and skills to be developed in-country just to get the ball rolling.\n\nSuddenly, that tshirt costs $100, and the whole Walmart style consumer system that we currently experience falls to pieces. The system works because we supply to the global marketplace where we have advantage and buy what we can't make as easily or cheaply.",
"The simplest way to concisely describe the benefits of trade is with [comparative advantage](_URL_0_). To put it as briefly as possible, some countries produce some things more easily, while other countries produce other things more easily. An easy example to understand is tropical fruit. Several tropical fruits like pineapples and bananas and so forth require warm temperatures and lots of water to grow, so it's easier to grow them in places that have warm weather and more rainfall. It's possible to grow them in other places too, but it requires more work. So if a place that has an easier time growing pineapples grows more pineapples than it needs, and then sells some of them to another place that's colder and drier and can't grow pineapples so easily, the cold place gets to eat pineapples and the warm place can buy something else that they couldn't produce so easily by themselves.\n\nObviously it's not that simple if you're talking about something besides pineapples, but the same basic principle can still be applied in a general way to other products. Making cell phones doesn't have much to do with the weather, but if circuit designers are easier to find in this country, and big electronics factories are easier to build and factory workers are easier to find and cheaper to employ in that other country, then the cell phone manufacturer can to put their design offices in the first country and their factories in the second and end up making more cell phones cheaper than either country could do if there was economic isolation."
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23tv8i | computer science and discrete math | I'm a CS major finishing up calc 1 and taking discrete math this fall. Why is discrete math important in computer science? I understand that Boolean algebra is important, but why abstract topics like rings and fields or proofs? Where do they come into play, if at all? Where is that knowledge applied or useful? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/23tv8i/eli5_computer_science_and_discrete_math/ | {
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"Very good question. There are a ton of topics in discrete mathematics that have applications to computer science. Here are a few of them:\n\n* logic: let's say that you want to prove that a program is correct, or automatically generate a proof that a theorem is correct. Discrete maths contains some of the intellectual building blocks you need to do this.\n\n* primality, ring fields, number theory, and abstract algebra, etc.: incredibly heavily used in cryptography and cryptanalysis.\n\n* polynomials: generating error-correcting codes, i.e., how to encode information in such a way that it is robust against the loss of parts of it. Useful for RAM, file systems and storage, internet transmissions\n\n* probability: useful in so many ways it's hard to count. Probabilistic machine learning and AI (e.g., Bayesian inference). Probabilistic algorithms, including monte carlo simulations, load balancing, robotic planning and positional estimation, etc. etc.\n\n* linear programming: a powerful tool for finding optimal solutions to constraint-based problems, such as planning the routes, crews, aircraft, and schedule for an airline.\n\n* graph theory: pagerank (a part of the search engine ranking algorithm that gave Google its initial edge) came out of this. Also, many analyses and algorithms related to networks, routing, distributed systems, social networks, and so on.\n\n* game theory: designing robust auctions and bidding methods (e.g., for advertising networks), analyzing algorithms and systems involving the interaction between mutually distrusting agents (e.g., network protocols, P2P systems and their incentive compatibility), and more\n\n* information theory: the design of compression algorithms, video encoders, faster broadband network modems, and more.\n\nThere's so much incredibly useful stuff in there.",
"Computers are inherently discrete, i.e. you are fundamentally dealing with bits at the lowest level which are discrete. It, then, shouldn't be too surprising that discrete math and computer science overlap quite a bit. Many discrete math problems are easy to formulate in a way that can be solved by a computer (which can't truly be said about other branches of math) and many computer science problems (like algorithmic problems) essentially boil down to a discrete math problem. \n\nThe answer to this question also depends on what you think computer science means. In a lot of ways, I see discrete math as a subfield of computer science. Maybe you think computer science is something else entirely. There is a common quote that I really like that I think makes you think about CS differently: \"Computer Science is no more about computers than astronomy is about telescopes.\""
]
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[],
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|
1xbsv8 | world superpowers tend to be huge. why don't smaller countries unite? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xbsv8/world_superpowers_tend_to_be_huge_why_dont/ | {
"a_id": [
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"text": [
"Like the EU and African Union?"
]
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[]
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||
59wdgm | dakota pipeline. why is the $3.8 billion pipeline moving oil from north dakota to illinois? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/59wdgm/eli5_dakota_pipeline_why_is_the_38_billion/ | {
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"A pipeline is the cheapest and most efficient way to move oil. Some other ways to move oil are tanker truck, railroad tanker, tanker ship, and barge. All of these methods are time consuming, limited, and somewhat dangerous. "
]
} | [] | [] | [
[]
] |
||
4zy5z1 | are memory palaces real? how useful/powerful can they become? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4zy5z1/eli5_are_memory_palaces_real_how_usefulpowerful/ | {
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"They don't increase your.. eidetic memory. You can't memory-palace glancing at a phone book and then remember the entire page. No one has a photographic memory of that sort as portrayed on television. It has to be something you're consciously trying to remember. \n\nBut it is a real thing, and it can help you memorize large numbers of things. There are memory competitions (World Memory Championship) where people memorize the order of multiple decks of playing cards, random numbers and words, names of strangers, etc., and they have amazing success mostly with just this technique. \n\nAnd while it isn't instant as on TV, it can work fast: the world record for memorizing the order of 52 cards is 18 seconds. This is still a long way from a phone book at a glance, but it still works pretty quickly once you get the trick down. ",
"the german wikipedia has an article:\n\n_URL_0_\n\n- > yes, it is real, mostly based on [this, the method of Loci](_URL_1_)\n\nyou can't know if somebody \"has one\", because 1. basically, everyone stores information, 2. if this information becomes more abstract / counter-intuitive, you need better keys to maintain access to the info.\n\noverly simplified, \"the palace\" is just excellent key-management - every room serves a specific field of interest.\n\nhave you ever smelled something for the first time in a while and remembered long-past stuff? here, the smell was your key.\n\nyou can't tell what somebody has smelled in his life before. \n\nhowever, you can study ones expertises and make assumptions to what his keys might be.\n\n"
]
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[],
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"https://de.wikipedia.org/wiki/Ged%C3%A4chtnispalast",
"https://en.wikipedia.org/wiki/Method_of_loci"
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2g0e05 | why do countries use civilian agencies for military intelligence (cia for example)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2g0e05/eli5_why_do_countries_use_civilian_agencies_for/ | {
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"There's a grey area between law-enforcement, military and dedicated intelligence when you're thinking about things like foreign-based terrorist threats or counterfeiting operations and other such things. Countries solve these things differently. \n\nCanada used to rely on the RCMP for intelligence related to threats within Canadian borders from foreign agents, but decided ultimately to go with a dedicated agency for such things.\n\nThey also rely on JTF-2 and other military assets for any violent interactions with threats that would generally be the domain of CSIS to discover and investigate. \n\nThe upside to a dedicated intelligence agency is that you can readily have it focus on investigations or keeping up with situation even if there's no possible military action going to be taken on it. Having law-enforcement do it isn't totally ridiculous, but it can be readily argued that foreign threats aren't really within the realm of 'law-enforcement'.\n\nAlso the government as a whole, not just the military, is going to be interested in the sorts of things one would have dedicated intelligence agencies doing. MPs and other government figures may approach CSIS or be approached by CSIS regarding information important to their position in the government.\n\nA dedicated intelligence agency prevents military biases or interests from getting involved in the information sharing with the rest of the government. If the military is the only way the government knows what's going on that's a government that can be manipulated easily by the military.\n",
"Civilian doesn't mean non-governmental, it means more or less non-military. "
]
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||
1vch4j | what's wrong with/why don't people like the ayn rand institute? | I glanced at the Facebook comments to [this](_URL_0_) NPR article and saw things like, " i stopped reading at 'ayn rand'" and "I smoke, but if the Ayn Rand institute approves of something I'm doing, I clearly need to quit immediately."
Thank you! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1vch4j/eli5whats_wrong_withwhy_dont_people_like_the_ayn/ | {
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"Lots of reasons, but one of them is that ARI defines Objectivism as a \"closed system\" -- that is, whatever Ayn Rand said is the beginning and the end of the truth, and anyone who thinks for themselves is explicitly unwelcome.\n\nEven if you buy into the rest of Rand's philosophy, that's a good reason to run away from the institute which claims to represent her."
]
} | [] | [
"http://www.npr.org/blogs/theprotojournalist/2014/01/15/262489772/quick-question-time-to-leave-smokers-alone?utm_content=socialflow&utm_campaign=nprfacebook&utm_source=npr&utm_medium=facebook"
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[]
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|
3c5tui | why do fireworks "pop" *after* they explode and not while they are exploding? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3c5tui/eli5_why_do_fireworks_pop_after_they_explode_and/ | {
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"Typically a firework will be some 10's or hundreds of meters in the air and some distance away from you.\n\nThe light from them reaches your eyes almost instantly, but the sound travels slower and comes a second or so later.\n\nIts the same reason you see the lightning immediately but don't hear the thunder untli some time later.",
"Fireworks *do* pop while they are exploding, but light travels much faster than sound. The light emitted by the firework reaches your eyes before the sound emitted reaches your ears.\n\nThis is true for everything, not just fireworks. If you stand at the end of a field and have a friend standing at the other end, they can clap their hands and you will be able to see them do it before you can hear the clapping sound they make."
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1nolyu | how do we refer to "locations" or "positions" in space? | In space everything is orbiting everything else and there's no such thing as a "fixed" position or point of origin. Ok, sure, so then how do we refer to positions?
Say I'm from another planet and I want to tell you to meet me at a particular moon orbiting a particular planet orbiting a particular star, how the hell do I do that?
| explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nolyu/how_do_we_refer_to_locations_or_positions_in_space/ | {
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"There would generally need to be some sort of previously agreed upon reference point. And from there it's a continuing series of relative reference points. \n\nIf our agreed upon reference point is the center of the Milky Way Galaxy, we could pretty easily superimpose a coordinate system over it, and identify most stars with enough precision. Stars do move, but they're generally far enough apart and move slowly enough relative to those distances that it's not a problem over short time scales. \n\nOnce you've got the star figured out, then it's probably best to come up with some sort of local system for that specifics of that system. I'll be in geosynchronous orbit around the second moon of the fourth planet from the star. \n\nThere might be a little confusion if the planets orbits aren't easily apparent, or cross or whatever, but there are probably other ways of distinguishing. We've got 8 full blown planets, and a few minor planets in our solar system, and they're generally very different from each other. I'll be around Venus, it's the 2nd planet, covered in clouds of sulfuric acid. Meet me at Neptune, it's the big blue gas giant, you can't miss it.",
"You always have to define a reference point. It doesn't matter where that reference point is, though it sure as hell helps to have it be something that makes sense, like the center of a planet or star or galaxy.\n\nThere's no way at all to pick a reference point that isn't arbitrary, though. None at all. You always have to say something like \"149 gigameters from the Sun at a polar angle of 7.5 and azimuthal angle of 90\" or whatever, and you'd also have to define what you mean by \"polar\" and \"azimuthal\" angles since those are arbitrary choices."
]
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lzdl4 | economic growth. | What does it mean when the economy grows by 4%?
Edit: and why does growth benefit stockholders? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/lzdl4/eli5_economic_growth/ | {
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"Let's say a company that makes TVs manages to make 10% more TVs this year than they did last year. We say that company \"grew.\" That's usually good for stockholders, because it usually means they're making more profits.\n\nNow, if you add up the total dollar value of the stuff that all the companies made this year - all the TVs, all the cars, all the shiatsu massages, all the yards landscaped, etc - the total value of everything we made is our \"gross domestic product.\"\n\nIf that's bigger than last year, we say \"the economy grew.\" If our companies made 4% more stuff than last year, then we say the economy \"grew by 4%.\"\n\nSo when the economy grows, it just means that companies are making more stuff. Or, possibly, higher quality stuff. Which usually means those companies are making more profits. That's good for stockholders.\n\n",
"Let's say a company that makes TVs manages to make 10% more TVs this year than they did last year. We say that company \"grew.\" That's usually good for stockholders, because it usually means they're making more profits.\n\nNow, if you add up the total dollar value of the stuff that all the companies made this year - all the TVs, all the cars, all the shiatsu massages, all the yards landscaped, etc - the total value of everything we made is our \"gross domestic product.\"\n\nIf that's bigger than last year, we say \"the economy grew.\" If our companies made 4% more stuff than last year, then we say the economy \"grew by 4%.\"\n\nSo when the economy grows, it just means that companies are making more stuff. Or, possibly, higher quality stuff. Which usually means those companies are making more profits. That's good for stockholders.\n\n"
]
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n6cws | the diamond industry | The reddit hivemind seems set against the diamond industry and all its evils. All I've really heard is that leaders in the industry only sell a fixed amount of diamonds per year, keeping demand high. I also have a small amount of knowledge concerning blood diamonds, but not enough to really understand how much (if any) that still plays in current times. Is there anything big I'm missing?
Also, are there any videos/documentaries I could learn more from that provide enough good information without being too biased?
Thanks in advance! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/n6cws/eli5_the_diamond_industry/ | {
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"To my knowledge, there are three things people have problems with the diamond industry for. How accurate these perceptions are is debatable.\n\nOne, DeBeers, the diamond cartel, only releases a small number of their diamonds for sale, keeping *supply* (not demand as in your OP) artificially low. Low supply jacks up the price, DeBeers makes money.\n\nTwo, the diamond industry as a whole promotes diamonds as a \"This is the only thing that matters to show your woman you love her. Artificial diamonds are for artificial love\". Now, what a carbon-based rock has to do with love is beyond me, but this marketing campaign keeps diamond demand artificially high, which also jacks up the price.\n\nThree, diamonds are fungible. This means one diamond of the same size, shape, etc, is just as good as another. For example, water is also fungible: you don't care if it came from the tap, bottled water, or is a French import, it's all H2O (unless you care about intangibles likes artisan water). Non fungible goods are things like art, where the Mona Lisa is not worth the same as a kindergartener's drawing even if they are the same size. Since diamonds are fungible, the price is the same no matter where they come from. \"Blood diamonds\" (aka conflict diamonds) are often mined under inhumane circumstances and sold to support local warlords. Since diamonds are fungible, the warlords will get a good price for them even if most people buy \"conflict-free\" diamonds, because they few people that buy conflict diamonds get them from the warlords for the same price. Incidentally, the same situation occurs with oil, where even if the US doesn't want to buy oil from, say, Iran, if the US demand for oil goes up, the price Iran can charge also goes up.\n\nSo, artificially low supply + artificially high demand = artificially high price, plus indirect support of warlords.",
"I'm a hobby gemcutter. I've never worked with diamonds, but I know a fair bit about how other gems work, and I've read a [good book on them,](_URL_2_) and talked to people in the industry, in person and online.\n\nFirst the reason there is (or was) a diamond cartel. Unlike other stones, diamonds are found in only a few locations. They are formed deep in the mantle, they only surface when kimberlite or lamproite happens to grab chunks of diamond bearing rocks on their way to the surface. Those two rock types form in titanic geological steam explosions. But where they exist, diamonds can survive having the host rock blasted and crushed, and they can be seperated from tons of rock because they are tremendously hydrophobic- they are attracted to grease, they stick to a conveyor belt of grease while water washes other rock away. They are also found in river or ocean gravel downstream of the host rock, they don't wear down much. These alluvial diamonds are the blood diamonds the artisanal miners in poor countries are after.\n\nThe diamond mining companies spend many millions of dollars mining diamonds, they wouldn't do it if they were just sitting on a huge supply. What they have done is markeet diamonds very effectively as the ultimate gemstone, and as the standard choice for engagement rings. That last point is utter bullshit.\n\nJewelers really get behind it though, because most jewelers aren't artists, and they aren't gem experts. All but a few diamonds are some shade of white, they come in a limited range of sizes and shapes. Diamond grading is complex, but exact. Sapphire comes in literally every color, including clear, parti- color, and color change (red sapphire is called ruby). Spinel is so similar to sapphire that only an expert with test equipment can tell a spinel from a sapphire. Then add similar levels of complexity to topaz, tourmaline, chrysoberyl, beryl... Jewelers are more comfortable with diamond, the guy at the mall doesn't know how to design a custom setting for a three carat cat's eye tourmaline.\n\nAs far as blood diamonds, that is as much hype as diamond engagement rings. There is just as much [Blood tin](_URL_0_) or [Blood coffee](_URL_1_) on the market. You would probably improve the world most by limiting your consumption of petroleum.\n\n",
"To my knowledge, there are three things people have problems with the diamond industry for. How accurate these perceptions are is debatable.\n\nOne, DeBeers, the diamond cartel, only releases a small number of their diamonds for sale, keeping *supply* (not demand as in your OP) artificially low. Low supply jacks up the price, DeBeers makes money.\n\nTwo, the diamond industry as a whole promotes diamonds as a \"This is the only thing that matters to show your woman you love her. Artificial diamonds are for artificial love\". Now, what a carbon-based rock has to do with love is beyond me, but this marketing campaign keeps diamond demand artificially high, which also jacks up the price.\n\nThree, diamonds are fungible. This means one diamond of the same size, shape, etc, is just as good as another. For example, water is also fungible: you don't care if it came from the tap, bottled water, or is a French import, it's all H2O (unless you care about intangibles likes artisan water). Non fungible goods are things like art, where the Mona Lisa is not worth the same as a kindergartener's drawing even if they are the same size. Since diamonds are fungible, the price is the same no matter where they come from. \"Blood diamonds\" (aka conflict diamonds) are often mined under inhumane circumstances and sold to support local warlords. Since diamonds are fungible, the warlords will get a good price for them even if most people buy \"conflict-free\" diamonds, because they few people that buy conflict diamonds get them from the warlords for the same price. Incidentally, the same situation occurs with oil, where even if the US doesn't want to buy oil from, say, Iran, if the US demand for oil goes up, the price Iran can charge also goes up.\n\nSo, artificially low supply + artificially high demand = artificially high price, plus indirect support of warlords.",
"I'm a hobby gemcutter. I've never worked with diamonds, but I know a fair bit about how other gems work, and I've read a [good book on them,](_URL_2_) and talked to people in the industry, in person and online.\n\nFirst the reason there is (or was) a diamond cartel. Unlike other stones, diamonds are found in only a few locations. They are formed deep in the mantle, they only surface when kimberlite or lamproite happens to grab chunks of diamond bearing rocks on their way to the surface. Those two rock types form in titanic geological steam explosions. But where they exist, diamonds can survive having the host rock blasted and crushed, and they can be seperated from tons of rock because they are tremendously hydrophobic- they are attracted to grease, they stick to a conveyor belt of grease while water washes other rock away. They are also found in river or ocean gravel downstream of the host rock, they don't wear down much. These alluvial diamonds are the blood diamonds the artisanal miners in poor countries are after.\n\nThe diamond mining companies spend many millions of dollars mining diamonds, they wouldn't do it if they were just sitting on a huge supply. What they have done is markeet diamonds very effectively as the ultimate gemstone, and as the standard choice for engagement rings. That last point is utter bullshit.\n\nJewelers really get behind it though, because most jewelers aren't artists, and they aren't gem experts. All but a few diamonds are some shade of white, they come in a limited range of sizes and shapes. Diamond grading is complex, but exact. Sapphire comes in literally every color, including clear, parti- color, and color change (red sapphire is called ruby). Spinel is so similar to sapphire that only an expert with test equipment can tell a spinel from a sapphire. Then add similar levels of complexity to topaz, tourmaline, chrysoberyl, beryl... Jewelers are more comfortable with diamond, the guy at the mall doesn't know how to design a custom setting for a three carat cat's eye tourmaline.\n\nAs far as blood diamonds, that is as much hype as diamond engagement rings. There is just as much [Blood tin](_URL_0_) or [Blood coffee](_URL_1_) on the market. You would probably improve the world most by limiting your consumption of petroleum.\n\n"
]
} | [] | [] | [
[],
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"http://www.vqronline.org/articles/2010/fall/scrank-tin-fever/",
"http://ihscslnews.org/view_article.php?id=43",
"http://www.amazon.com/Nature-Diamonds-George-Harlow/dp/0521629357"
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"http://www.vqronline.org/articles/2010/fall/scrank-tin-fever/",
"http://ihscslnews.org/view_article.php?id=43",
"http://www.amazon.com/Nature-Diamonds-George-Harlow/dp/0521629357"
]
] |
|
1sq566 | why is the united states make such a big deal about the idea of 'spreading democracy'? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1sq566/eli5_why_is_the_united_states_make_such_a_big/ | {
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"It is a euphemism for securing access to natural resources via toppling governments that are unfriendly. We don't \"spread democracy\" in countries that don't have things that we want.",
"It's an easy way to sell actions that might otherwise be unpopular, basically.",
"It's also for security reasons. There is a theory that democracies don't fight each other. "
]
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275pl3 | is it possible to make a solution of salt and water that doesn't hydrate or dehydrate you? | I know that drinking sea water dehydrates you, but is this possible? Like a perfect mixture of regular and sea water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/275pl3/eli5_is_it_possible_to_make_a_solution_of_salt/ | {
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"text": [
"Yes. It's called an isotonic solution. The saline they give you in hospitals to rehydrate you is isotonic, and contains .9% salt by volume."
]
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2qtm1m | why does the us have a 3 school system (elementary, middle, high)? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qtm1m/eli5_why_does_the_us_have_a_3_school_system/ | {
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"6th through 8th/9th grades are considered an especially important time developmentally, so they are put in a smaller school for that. It also serves as a transition to high school.",
"Well I'm just here to say that's not how its set up in all of the US. I had elementary school and high school and that was it. Elementary school lasted 10 years (preschool-8th grade). ",
"It should be noted that many Catholic schools in the US have a K-8 and 9-12 configuration. Whether or not it is better than the 3 level system is open for debate. It might also have to do with finances, two schools vs. three.",
"Government operated schools in the USA often went until around age fourteen with the expectation that students would then enter into apprenticeships or work in the family business.\n\nAs the economy changed, more parents wanted their children to be eligible for office employment. At the time, office workers came from the educated elite who attended preparatory schools. The government-operated high school was an attempt to emulate this.\n\nAt the same time, many school populations were rising, requiring the building of more facilities. Some suggested that, instead of just building more elementary schools, the existing schools could have their age range reduced and a new facility could be built for early-pubescent students which would act as a bridge between the elementary system and the high school system. This would be called a junior high school and later a middle school.",
"You don't really want adults (12th graders are 18 years old) to have to share a school with 5 year olds. By separating the age groups, they have less interaction with the young kids, who would just be disruptive. (Both ways: young kids can be a distraction and the older kids/adults can be a bad influence). \n\nAlso, they have different playground requirements. Kindergartners really don't need 10 foot tall basketball hoops. High schoolers don't play on monkey bars. \n\nSome school districts separate into two different schools. Typically K through 8 in one school and 9 through 12 in another school. \n\nIn districts that have a middle school, it's typically 7th through 8th or 6th through 8th. The reason I've typically seen for this is because the young teenage years are very formative and separating them allows them to prepare for high school in a more thorough manner. The reasons I've seen for not separating them is to give more leadership opportunities for the kids. \n\nE.g., if a district had 25 K-8 schools and 5 high schools, if you separate them, they might end up with 17 K-5 schools, 6 middle schools, and 5 high schools. So there would only be 6 class presidents, 6 basketball teams, etc. As opposed to 25 class presidents and 25 basketball teams."
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6rzruw | why do manufacturers sell their products in a lot of poor countries, instead of focusing on only the wealthy ones? | I live in Lithuania (lower economy level) and recently been in Norway. The prices are x3 compared to my country there, so it got me wondering, why does Coca-Cola bring products to countries like mine, where they get x3 times less profit, instead of focusing on only the wealthy ones? Is it only because wealthy countries wouldn't consume it all, and so they get a bit extra profit? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6rzruw/eli5why_do_manufacturers_sell_their_products_in_a/ | {
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"Did you go anywhere in Norway where you couldn't buy Coca-Cola because it was sold out? I'm gonna guess that you didn't. So either Coca-Cola stops producing more than they can sell in Norway (giving them 0 extra profits), or they produce more and sell in a different country for less profits (giving them some extra profits).\n\nAlso, remember that a lot of the price difference is because of taxes, regulations and wages, so Coca-Cola the company might not actually see that much more profit from Norway vs. Lithuania.",
"My question for you is- are you going to buy up a ton of the same candy, travel back to Norway and sell it for 2X more and undercut those stores by 33%? ",
"They adjust prices based on what people are willing to pay in an area. It doesn't cost Coca Cola anywhere near $3 to produce a bottle of coke in the United States, but they can get away with selling it for that much in the United States because that's how much people standing in the line at a grocery store will be willing to pay. Likewise in a country where average incomes are a third of the average income of the united states, they probably won't sell coke for the equivalent of $3 a bottle. But the production cost is still the same, only a few pennies a bottle. They aren't losing any money by selling their product in lower income areas. They are just making a bigger profit margin by selling in higer income areas and marking up the price higher. They would however be losing out on profits of they simply cut out entire markets like Lithuania, just because the profit margin is smaller there than it is in Norway. They are still making a profit by selling in Lithuania, just not as big of a margin as in Norway.\n\nProfit margin isn't the entire story either. Sales volume is a big part of it too. Even if they could sell coke for $6 a bottle in Norway and $0.50 in Lithuania. If Norwegians didn't like coke and never bought any, they wouldn't be making any profit by offering it in Norway. Conversely if Lithuanians loved coke, they could be potentially raking in the cash even if the were selling it for super cheap in Lithuania compared to other countries.",
" > Is it only because wealthy countries wouldn't consume it all, and so they get a bit extra profit?\n\nThat's exactly why.\n\nLet's say it costs you 0.05 to make a can of coke. You can sell it in Norway for $2, but you can also sell it in Lithuania for $0.75.\n\nSelling in Lithuania doesn't hurt your sales in Norway(it's not worth trucking a bunch of $0.75 across the border, paying extra taxes etc), so the more you can sell, the more profit.\n\n\nYou do actually see this problem with software/textbooks-things where it's either free to transport, or it's worth paying the transport costs- those companies have gotten around that by using either software lockout or laws to prevent it. A lot of movies/games are region-locked.\n\nEdit:\nAnd even if people did do it, they might still make overall more profit. If they make $1000 in Lithuanian sales, and people undercut them in Norway and they lose $500 in potential sales, they're still up overall. It's unlikely other companies can do it efficiently, but as long as it's more profit, they won't really mind. Though they might adjust prices if they think they can earn more profit.",
"It still makes profit. Would you be willing to pay 3 times more for the range product ?most people no , things are scales to the economy. Come can't charge to much in one area due to either it not being obtainable or regulation, but can elsewhere. Now some products are only for the wealthy but not others. Coke would make less selling a few cans a day to the 1% than it does selling to the 99%. At the end of the day if they will sell the product as high as they can while maximizing profits, if they doubled price but cut their sales by 2/3 then they make less."
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678417 | why is the ping high even when you have a fast internet connection sometimes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/678417/eli5_why_is_the_ping_high_even_when_you_have_a/ | {
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"Your connection is only one small link in a potentially long chain. It's like saying your house is on a high-speed expressway, so why does it take a long time to drive somewhere sometimes?\n\nIf your network packets have to travel a long distance, e.g. if you are far from the systems you want to connect to, or if they have to wait to transit a very busy connection, then your roundtrip (\"ping\") time will be higher than if none of those things are true.",
"Latency (that's ping time) and bandwidth are not really closely linked at all. To take the extreme case, a lorry full of hard drives can have a bandwidth easily in the tens of gigabits per second - potentially even *hundreds* of gigabits per second depending how fast and far it's travelling - but the latency is *atrocious*. Even outside of that, satellite connections can provide a good example: there's no reason they can't transfer a huge amount of data per second, but the speed-of-light delay is necessarily longer than with an optic-fibre link, for example. Those are reasons an individual connection can be high-bandwidth (\"speed\", but note that perceived speed depends on latency as well) yet also high-latency. Then there's what u/yes_its_him mentions about your connection not being the only one involved - amongst other things, the backbones are generally pretty reliable, high-bandwidth, and low-latency, but geographic distance still has an impact, as does the connection at the \"other end\".",
"In easy terms:\n\nThe higher your ping, the further away from the server you are. The lower your ping, the closer to the server you are.\n\nNot so easy explanation:\n\nSo if there's a server with +100 ping, this means you are further away from the server and it takes longer for you to communicate with the server. Which results in the server taking longer to reply back to you, which means it takes longer to update the information on your screen.\n\nSo let's say you're playing an online game (I'll use Team Fortress 2 as the example), you've just joined a server with +200 ping. This means what you see on your screen isn't actually what the current game state is, to other players you're either moving (more like teleporting all over the place) or your character isn't moving or your moving at a very slow pace, so it appears that it takes forever to walk out a door or to go around a corner. This also means when you fire your gun or swing your melee weapon, you won't be able to hit your target as your actions are delayed by your high ping. This also explains how you get shot even though your behind a wall, because on the screen of other players your still in their sightline, however your game (due to your ping) makes it appear as though you weren't in sight, but were killed nonetheless.\n\nIt's always best to join servers within your country of residence, so that you can always have decent ping. However if you do play on servers that aren't within your country of residence, try to play on servers that have low ping. Don't go joining servers with +300 ping (especially if you get 800 ping on the server). "
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50ri28 | what happens (legally) to nazis that are caught nowadays or the past ten years (given their age) once they are caught? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/50ri28/eli5_what_happens_legally_to_nazis_that_are/ | {
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"They go to trial and get sentenced to some prison time. But due to the advanced age they probably can sit it out at home under house arrest. \n\n[This is the latest case of a 90+ year old nazi who got sentenced to 5 year of prison](_URL_0_)",
"They are extradited to the appropriate country to stand trial when they don't already live there. (Usually Germany, though not always)\n\nGenerally they are charged rather harshly and then sentenced rather lightly (Reinhold Hanning was found guilty of 170,000 counts of accessory to murder and sentenced to 5 years).\n\nTrials of former nazis are now more about recognizing the crimes than about punishing the perpetrators. All the nazi bigwigs have been dead for decades."
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"http://www.independent.co.uk/news/world/europe/auschwitz-guard-guilty-accessory-murder-charges-jailed-five-years-reinhold-hanning-nazi-germany-a7087341.html"
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7yc7tj | how do holograms appear closer to the viewer? | I don’t know how to explain it exactly, but the image in the hologram display of the Lykan Hypersport seems closer when you look at it. How does that work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7yc7tj/eli5_how_do_holograms_appear_closer_to_the_viewer/ | {
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"Your eyes can‘t see distance. Instead both of your eyes see slightly different views of the world in front of you. The more those views differ the closer your brain thinks an object is. That‘s what you perceive as distance. Holograms like the one you described use optical effects to show a slightly different image depending on the angle you look at it. So your brain thinks the object must be closer than it really is, because the images differ more than usual for the actual distance."
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vhow0 | ion thrusters | Edit: I found a fairly good explanation by [NASA](_URL_0_) if anyone is interested. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/vhow0/eli5_ion_thrusters/ | {
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"Take a heavy particle which has a charge, such as a proton. and put it in an electromagnetic field so that it moves. When it moves, the thing creating the field moves the opposite way (because all actions have an equal and opposite reaction) which creates thrust. Do this a lot of times, and you can create enough thrust to actually move an object on human or even planetary scales.",
"Sit on a small boat on a lake. Now pick up a heavy ball and throw it towards the shore. You and the boat will be pushed out further into the lake. The heavier the ball, and the faster you can throw it, the more you will be pushed out.\n\nIon thrusters use a lot of very, very tiny balls that are moving really, really fast. They're still tiny, though, so they don't move the craft very much. It wouldn't work for a boat on Earth, because all those tiny balls wouldn't be able to overcome drag from the air and water; a brisk wind or current would push you more than an ion drive. It still works in space, because there's almost no drag to worry about. Since those balls are so tiny, you can bring up huge numbers of them without adding much mass to the craft and you'll still be able to run it for a long, long time.",
"An ion thruster works by shooting very small particles out the back of a spacecraft in order to make it move forward in space.\n\nLet's try it at home! For this first part, you're going to need roller skates and a bowling ball. Stand on a flat surface with your skates on, take the bowling ball, and throw it as hard as you can straight out away from you. Did you move backwards? You probably did! That is the result of something called Newton's 3rd law, which you might have heard said as \"for every action, there is an equal and opposite reaction\".\n\nIt turns out, if you throw the ball even harder, you'll move even more! But this could get hard to do if you want to keep going faster. To do so, you need to throw even harder, but you can't because you're just a 5 year old. The other way would be to bring more bowling balls, but they're heavy and carrying more than one or two could be hard.\n\nSo what to do? Well, you could throw even smaller balls even faster if you have something like a machine gun at home! You might want to ask your mom first, then go grab her machine gun, put your rollerskates back on, and now trying spraying your neighbor's garage in a hail of lead. Notice how you've moved backwards even more? This is because the action is a product of the weight of the thing we're throwing (bowling balls are big, bullets are small) and how fast we throw them. We can't throw bowling balls fast, but mom's machine gun can throw lots of bullets very fast!\n\nAn ion thruster works with even smaller bullets thrown SUPER FAST! In fact, what an ion thruster is throwing is something even smaller than an atom, and that's very small indeed. We \"throw\" these ions using magnets and electricity, and we throw them close to the speed of light, which is the fastest you can throw anything! It's so fast that even these super tiny \"bullets\" are enough to get you moving if you throw enough of them. And because these \"bullets\" (ions) are so tiny, we can carry more than we could ever need - unlike those bowling balls.\n\ntl;dr - listen to your mom or she'll fuck your world up"
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c9kzzk | why do corporations get rid of their ceos so eagerly? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c9kzzk/eli5_why_do_corporations_get_rid_of_their_ceos_so/ | {
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"A CEO, especially at a large company, is the driver behind how the corporation as a whole is moving forward. They either creat or OK the ideas that define everything at the company, so if they’re not succeeding at hitting the benchmarks set forward by either the owner, investors or board of directors, they will often be replaced for someone else with a different “vision” or way of getting things done.",
"A CEO is paid so much because they are the punching bag for shareholders and the public. If things go wrong, no matter what the issue is, they can fire the CEO and get another one, signifying that whatever was wrong with the company is gone now. Action taken, confidence restored.",
"A CEO must lead the company, and vision and forethought are critical traits. Failing to establish a vision, and leading to ensure others understand and execute that vision is a huge shortcoming and grounds for immediate dismissal. By the time someone sits in the CEO chair, he or she has made and learned from all the mistakes needed to be prepared for the role. Not to say they can't still make and learn from mistakes, but they can't be of such magnitude that their company falls way down the competitive ladder vis a vis others in their industry.",
"In theory, the job of a CEO is to appoint and direct the managers of the company in whatever way maximizes the stock value of the company. If people think the company is profitable, in a growing market, has good opportunities, reliable workers and good leadership, the stock value goes up. If that isn't true, stock value goes down. \n\nIn practice, the job of a CEO is to make people think that whenever something goes right, it was because the company has one of those stock-value-enhancing positive traits. Usually good leadership if they can convince people of that idea, but anything works. When something goes wrong, their job is instead to convince people that the company has already fixed the problem, that the problem was due to bad luck/outside interference, or that there actually isn't a problem at all. It is helpful (but not critical) for the company to actually be making a profit, but the CEO doesn't really have much influence over how well the company is doing - at best, they can push the company to focus on short term profits (which make the CEO look good) at the expense of long term gains (which are healthy for the company as a whole).\n\nIf the CEO does a bad enough job, the board of directors will use them as a scapegoat like you suggest, but they don't like doing that since it makes the company look like idiots for hiring such a bad CEO in the first place.",
"Because share prices plummet if companies are not seen to be addressing shortcomings. It's not really about anything more than that. The market won't wait for a CEO to learn from their mistakes. People just want maximum return from their investment",
"This is actually a result of a logical fallacy where people place too much blame on a leader. It happens in sports as well with how quickly coaches are fired even if they have inferior talent. It’s the result of lazy thinking and taking the easiest action on the table. Instead of doing the work to diagnose a problem fully, decision makers, such as board members, take the easy way out and just throw money at the problem. This isn’t to say there aren’t bad leaders, just that people are unwilling to put in the time and effort to effectively diagnose organizational failure.",
"Usually this happens when CEO does not share the vision of the board of the directors. So maybe the BMW CEO express a lot of skepticism towards electric car and is unwilling to spend more resources on them, or the CEO is terrible at execution and the board of director can actually find someone they know that's better at doing their job. 90% of the time is due to misaligned visions because even if a CEO had a few misses in the execution, there is absolutely no guarantee that they can find someone that is going to do a better job than that person.",
"It’s not so much that they can’t learn from the mistake as it is there are better candidates for the new path. In many cases, a CEO getting fired signals a major strategic shift within the company. The old CEO may have learned that they should have switched course sooner, but they may not have the skillset needed to follow the new path. \n\nThink of a company like Kodak. They eventually realized that digital cameras were the future, but at the same time, the mistake of ignoring this technology was made because the CEO could not comprehend it could ever replace physical film. It would make little sense to leave the same leader in charge to figure out how to change their company to adapt.\n\nDemoting isn’t much of an option either, office politics would create way too many headaches in most cases.",
"Ill sum this up a lot more Succinct then everybody else. One wrong decision can end a corp. if you continue to let the top guy make wrong decisions your entire company may not survive. \nThus hasty moves need to be made sometimes.",
"Don't you stress out about the CEO. Even if they bankrupt the company they land safely with a golden parachute."
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4gbqaa | what are those random pains you get sometimes, such as in a toe or arm, that then quickly go away and you never feel again? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4gbqaa/eli5_what_are_those_random_pains_you_get/ | {
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"Just to clarify here, folks, I'm not talking about muscle cramps. I know what causes those bastards. I'm just talking about extremely brief, random pains in random places in your body. Might not even be that bad. I know the human body is incredibly complex with a ton of things going on constantly, and I'm curious what causes these occurrences in particular. "
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2h31wb | what's happening in argentina financially? why can't argentinians buy the dollar? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2h31wb/eli5_whats_happening_in_argentina_financially_why/ | {
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"Argentina has been having financial problems since the 1930s, but back in 2001 the government stopped payment on $100 billion in their debt. Yes, with a \"B\". Since then the government had been spending more than they took in and could afford, printing money and devaluing the currency resulting in high inflation. Argentina seems set for another default, which would just make it that much harder to claw their way out of the economic shitter.",
"We've had economic crisis throughout the 20th century and even started the 21st with one. Due to this argentines are mental about the dolar because usually our inflation rockets and our currency isn't worth shit (we've dropped 13 0's with 4 currency chsnges in the second half of the past century alone). Because of this argentines are mental about the dollar and we run to it once things to go sour (about once every 10 years: 1976,1989,2001 and now).\n\nSooo this the reason we always want dollars. But guess what? Govt. needs dollars to pay debts and realize imports but due to the shit economic policy we carry no one invests here and thus no dollars come in. Also we export less and less due to the high taxes they placed on agricultural sector.\n\nSo whats the draconian solution? 1. Prohibit purchase of dollars to the general public and 2. Limit imports.",
"Saying that people cannot use the dollar OR that people cannot use the dollar \"legally\" are two different things.\n\nIn any state where there is a general economic collapse there will be a run to a foreign currency (which the government may not want to provide to you) and the creation of a black market. \n\nBasically it means any savings you have in local currency are majorly screwed and you will probably have to hustle to figure out how to each enough of the parallel currency to buy scarce goods on an overpriced black market."
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tkupc | why is widescreen the preferable way to view screens? and why these specific ratios? | I'd like to know why it is that widescreen is the preferred viewing format for screens. I know the obvious "you can see more on the sides, they aren't cut out" but...why are the filmed like that? Why did we decide that widescreen is the way we'll do our movie screens, and more recently TVs and computer monitors?
Also, how and why did we decide on the specific ratios that we did? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/tkupc/eli5_why_is_widescreen_the_preferable_way_to_view/ | {
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"Cinema screens started off square (or nearly square, they had a ratio of 1.33:1), and when tv started it followed the same ratio. Cinema audiences started to drop because more people were staying home to watch tv, so movies got wider in an effort to entice people back to the cinema. It's also a more \"natural\" scope of view, due to the way human peripheral vision works.",
"Because our vision is naturally widescreen -- our eyes are next to each other horizontally and are wider than they are tall, so we have far more horizontal vision than vertical -- so it makes more sense to us. And it makes more sense for composition, too. A wide composition lets you have multiple people standing next to each other in the same shot, which you wouldn't do as easily with a square composition.\n\n > Also, how and why did we decide on the specific ratios that we did?\n\nBack before movies existed, the standard for photographic film was 3:2. That's 3 centimetres of width for every 1 centimetre of height. I don't know why; I guess it just seemed like squarish was a good shape at the time. They weren't trying to replicate comfortable human vision, they were just taking portraits with clunky early cameras. But when movies came along, they went with the standard film size being produced, because that was easy, it was already being made.\n\nThen, in the late 20s, sound came along. To include sound information on the film negative, they cut into the shape a little, and made the Academy ratio (1.37). This was the ratio used for basically every movie from the late 20s up to the 50s, and popularly for a while after. This is the shape Casablanca and Citizen Kane are in.\n\nWhen TV was invented, they made it in the 1.33:1 shape, which we call 4:3 due to the ease of using whole numbers. If I've ever learned why they went with 1.33 over 1.37, I've forgotten it, so sorry about that. But they're damn close. This is the shape old TV was, the shape we used right up until ~2001. When 1.37 movies are shown on 1.33 TVs/DVDs, they usually clip a little bit off the sides so it fits.\n\nIn the 50s, TV started getting huge, and the movie studios all started panicking, thinking \"oh crap, if people can get unlimited entertainment at home for free, why would they ever come to the cinema?\", so they did two things to make cinemas more attractive. The first was switch to producing virtually everything in colour, which TV couldn't do. Prior to this, only big-budget musicals and major releases like Wizard of Oz and Gone With the Wind had been done in colour, but from the mid50s onward, they spent the extra money and did all but the lowest-budget products in full colour. Second, they invented widescreen.\n\nDuring the 50s and 60s, a lot of different film and camera manufacturers invented a lot of different types of widescreen, all competing to be the new standard. In the US and Asia, 1.85:1 became the new standard ratio because it was plenty wide, but didn't require any really new techniques or equipment to use. 2.40:1, or Scope, became a \"premium\" format used for some high-budget productions and 'epic' films. In Europe, Australia and the UK, 1.66:1 became the standard because it was considered to be a happy medium between the traditional ratio cinemas were built for and the fancy new widescreen ratios. \n\n1.66:1 is the ratio you'll see watching Barry Lyndon or a lot of old Disney movies. 2.40:1 is the ratio you'll see watching Lord of the Rings or Spartacus. 1.85:1 is the ratio you'll see most commonly.\n\nWhen HDTV came around, they had the opportunity to create a new size for TV. There was a lot of debate over what size to make it, and it was finally settled on 1.78:1 because that's the exact ratio that results in the least amount of unused screen space for someone who watches 1.33, 1.66, 1.85 and 2.40 aspect video equally. 1.78:1 is the shape of your TV and, usually, your computer screen.\n\nTV is produced specifically for 1.78 sets now, so TV matches perfectly. But movies aren't. This is why, no matter what movie you watch, you'll have some unused space on your screen. "
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64vm8o | why haven't hydrofoil boats become popular? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/64vm8o/eli5_why_havent_hydrofoil_boats_become_popular/ | {
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"They use a huge amount of fuel simply because they are going so fast. They seek to be lightweight to lift up properly, so their capacity is limited. They are loud. Many require fairly calm seas in which to operate at speed. ",
"They are for their specific niche use, but the problem is boats in general, at least for mass transit (not including leisure cruises) have been in massive decline for the last four decades. Ultimately, cheaper costs and travel times have made travelling by ferry pretty somewhat obsolete. In terms of personal use boats, there's not much need for Hydrofoils as regular hull and outboard do the job at lesser cost. Many catamarans are hydrofoils but again, this is a tiny niche as most people don't have several hundred thousand to spend on a sail yacht."
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2odksw | people always compare smells to rotten eggs, but i've never encountered this smell. what do "rotten eggs" smell like? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2odksw/eli5_people_always_compare_smells_to_rotten_eggs/ | {
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"Light a match. The smell that hits you when it is first lit is sulfur.",
"ever heard of \"fire and brimstone\" in reference to hell?\nBrimstone is sulfur....so hell.....it literally smells like hell.\nit is seriously pretty fucking gross.",
"Take some alcohol and react two moles with a mole of ammonia. You'll get some diethylamine. \nIt'll smell like rotting fish, not eggs, but you get the idea. \nAnyway. Have you ever been around fireworks? Black powder contains some sulfur, but not much. Not enough to do anything. Skunk stank has a bunch of thiols in it, which stanks because of sulfur. It's a chemical that living isms find repulsive because it's most commonly found around active sites of vulcanism, places like tar pits you could get stuck in and die, hot springs you could get boiled in and die, cooler hot springs you could drink and die, and lava that could burn in and die. All that is assuming the sulfur dioxide doesn't kill you first. It's not good for you. You do need some sulfur in your diet but not much. It increases the strength of tissues by making a stronger molecular bond between membranes of adjacent cells. If you burn a piece of skin really really bad, or hair, it'll smell bad because of the sulfur, but nowhere near as bad as rotting eggs, which produces the exact same kind of sulfur containing molecule found in those geological phenomena. \nEdit: don't use your own skin for this, use some leather or pig skin or cow skin or rawhide. And if you use your own hair cut it off first. And don't play with fire, because you're 5.\n",
"I really think that phrase results from someone trying to compare a smell to the worst smell in the world. Believe me, a real rotten egg smells way beyond regular sulfur. It's much more concentrated, maybe mix some sulfur with a dead animal body that has rotten."
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6wcr7o | why are nearly all children heavy sleepers when it varies more in adults? | I can pick my daughter up, carry her up a flight of 15 stairs and put her on the bed and she won't even stir, but if someone opens my door quietly I'll instantly be awake. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6wcr7o/eli5_why_are_nearly_all_children_heavy_sleepers/ | {
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"My kids doc recently explained it to me in relation to why adults wake up to use the rest room while kids do not. There is a gland that is not yet fully developed in children so it does not produce a certain hormone that makes us sleep less soundly. He said this is also why some kids wet the bed longer than others because the gland develops at a different rate. I'd then take a leap to saying it varies more in adults because that gland produces a different amount of the hormone in all of us."
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2e9j80 | why can't android get updates like windows does, bypassing the phone's manufacturer? | Both Windows and Android have to deal with vast number of devices of various manufacturers, but Windows can update itself while Android can't. I thought this might be caused by how phones need to be optimized for power and performance, but so do laptops.
Edit: In short, why doesn't Android devices get updates at the same time like Windows does? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2e9j80/eli5_why_cant_android_get_updates_like_windows/ | {
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"first of all, every manufacturer (besides of nexus series) is tinkering with android. so there is almost no \"pure android\" besides of official google products. this means that every manufacturer needs to change android.\n\nsecond thing, drivers. windows have many drivers, many things is plug and play, it doesn't work that way with android. android needs to be light, needs to be optimized for hardware. they can't add drivers for every part, it needs to be tested and needs to work on particular phone (or sometimes series of phones).\n\nedit: there can be even more delay if it's changed by operator. in this case it looks like this:\n\ngoogle is releasing new android - > manufacturer is changing it (like TouchWiz) - > operator is changing it (like adding even more bloatware).\n\ni'm not sure it's big case in USA, but probably is.",
"It's largely because Android is open source and can be changed by the manufacturer before they distribute an update. This includes the ability to change the update process, so only updates approved by the manufacturer and carrier are installed. Part of it also has to do with drivers and optimization, but it's largely the need for control over your phone.\n\nWindows is closed source, so the internal parts of it can't be changed (e.g. Windows Update) easily by a manufacturer, and in some cases, it might be against Microsoft's OEM agreement. Microsoft decides when to update. The most a manufacturer usually does to Windows before shipping a computer is install tons of garbage that no one uses.",
"In some ways, they have addressed this issue. Google broke up the core parts of the OS and they do get updated. Things like play services, each of the Google apps, boot services, etc. It allows them to update things without an entire rebuild of the system, and it's all delivered through the play store. Major updates to the overall system still need carrier approval because they could change things like radio firmware, and the carriers want to add their own stuff in too.",
"My contrary answer: it can get updates, but that's not the business or mindset that the carriers / third party device makers are in.\n\nFor Google, Android is an ongoing thing. They work on it, they improve it, they release new versions. But version 4.5 is the same product as 4.4, just a newer version of it. This is the Internet-age software / webdev mentality: continuous incremental improvement, and when I buy something, there's an understanding that I'm also buying some number of future updates.\n\nFor the carriers and phone manufacturers, the product is the *phone*. They put Android on it because it needs some kind of OS, and they tweak it to distinguish themselves from the competition, but once the phone is out the door they're *done* with it. That product has been sold, and it sold with whatever software was on it at the time. The next model of phone will sell with a later version of Android, but that phone is *a different product*. This is the hardware manufacturer mentality: each model, each *sale*, happens on its own. If I buy a 2014 model car, I don't expect the manufacturer to send me replacement trim and engine parts every year to upgrade it to the next year's model. Not only would that cost them money, but it would cannibalize some number of future sales.\n\nOf course, in practice, the mindsets blur together a little. Google won't support your phone forever, and hardware buyers get some amount of warranty service, support, recalls, etc. But the baseline attitudes and expectations of each industry are quite different.\n\n"
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5yqnee | why do airplanes use two-pronged headphones? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5yqnee/eli5_why_do_airplanes_use_twopronged_headphones/ | {
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"So you have to rent/buy the headphones on the plane and not just use the ones in your pocket.",
"So you won't take the headphones with you when you leave. It's an anti-theft measure. Headphones are cheap, but some people would still steal them. "
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zv3wk | why haven't more species of animals evolved out of having natural predators? | It seems to make sense that animals with natural predators would be killed, while those prone to no predators would survive. And yet, this is not true. Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/zv3wk/eli5_why_havent_more_species_of_animals_evolved/ | {
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"As the prey evolves so to does its hunter. Evolution also takes millions of years, we have only been around a few thousand. ",
"Prey species evolve lots of ways to avoid predators, like being faster/hiding better/fighting back, and predators evolve with them to get better at catching them.\nBut the prey don't need everyone to survive, just enough individuals to propagate the species. So instead of defenses, they can just have more babies, like rabbits and a lot of rodents."
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5gilyh | how is it possible to catch a ball without ever looking at your hands? | How is the body able to accurately catch an object without actually observing where the hands are in relation to the falling object? For instance, how is a juggler able to consistently use his/her hands to keep the objects in motion while only watching the peak of the arc? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5gilyh/eli5_how_is_it_possible_to_catch_a_ball_without/ | {
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"We actually have more than 5 senses. One of the other senses is [proprioception.](_URL_0_) You can feel where your body parts are without looking at them.",
"Thanks to unconscious processing, most of us instinctively know where our limbs are and what they are doing. This ability, called proprioception, results from a constant conversation between the body and brain. This adds up to an unerring sense of a unified, physical “me”.\n\nThis much-underrated ability is thought to be the result of the brain predicting the causes of the various sensory inputs it receives – from nerves and muscles inside the body, and from the senses detecting what’s going on outside the body. ",
"Bend your elbow.\n\nClose your eyes and tell me if your elbow is bent. \n\nYou can't see it, but your body does have sensors that let's your brain know where your body is in space. \n\nYour body doesn't have to look at your hands to know where you hands are. You brain already has that information. \n\nYour eyes look at the ball and your brain determines where your hands should be to catch the ball and if your brain picked the right place and your body places you in that place and your hands work right you just have caught a ball. \n\nThen again this is a skill which it pays to practice. With practice you don't have to think about it anymore...you just kind of do it. \n\nJust like when you spell the word cat your brain doesn't have to think C.....then A then T. \n\nYou just do it. \n\n "
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3i8v84 | how can stores like wal-mart or best buy legally check your receipt or search your bags? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3i8v84/eli5_how_can_stores_like_walmart_or_best_buy/ | {
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"Technically they can't. They can however ban you from the property if you refuse. Some business where you have to a member, will likely have a clause in the agreement where you consent to checks and searches by joining. ",
"Law school graduate here. You are correct that the 4th Amendment protects you from unwarranted and illegal searches and seizures. This, however, only applies to government officials or people acting on behalf of the government (e.g., informant on behalf of the government). You are not protected from searches by private individuals, which would be Best Buy in this case. *See, e.g., United States v. Jacobsen, 466 U.S. 109, 113 (1984).*\n\nThe Constitution is there to protect private individuals from governmental action. This is why you can get fired for telling your boss that you think he's an idiot, even though you have freedom of speech. I can go into more detail if you would like, but this should cover it.\n\nEdit: formatting, grammar"
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4c7ypk | why do sites immediately interrupt my browsing, asking me to sign up for their email newsletter? who signs up to a newsletter before seeing anything about the site? why is it a popular strategy to annoy site visitors like this? can i block these pop-up pleas? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4c7ypk/eli5_why_do_sites_immediately_interrupt_my/ | {
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"If you are on a PC you can use Ublock Origin. If you are on Android you will need root and you can install Adaway. If you use an Apple product I have no idea what you could do. \n\nEdit: corrected name",
"You could view it to marketing to the inexperienced internet users. They could perceive the pop up as a requirement for viewing the site. They fill out the form and the marketing base for that site just increased.\n\nSome of them make it less obvious you can close it too by fading the color of the close button, further targeting people who don't know any better.",
"I recently read they have increased newsletter subscriptions. The web is so data driven it seems fair to assume newsletter pop ups are working. At least for now. ",
"Saw a comment you have uBlock. You can specify it to block specific elements (the popup)\n\n[Before](_URL_3_)\n\nNotice the install firefox ad that snuck through\n\n[Step 2](_URL_1_)\n\nClick uBlock then the eye dropper\n\n[Step 3](_URL_0_)\n\nClick the element to block, then it will open up some code, click Create\n\n[Result](_URL_2_)\n",
"it increases earnings per visitor. when people opt-in to the newsletter, they get offers and advertisements in their email. you go from needing to get money from ads and on-page offers, to being able to market people through their e-mail.\n\nfor a long time, the trade-off was worth it: piss off some people to get opt-ins from others. \n\nnot that great of a strategy anymore, though. a better one is just to put a tracking pixel on your content and track people all over the place with well-targeted ads. no opt-ins, no stupid popups, and you can still market to people. best part is: 100% opt-in rate. if you read the content, too bad: tracking pixel. enjoy your ads.\n\nbut at least the ads you get will be better targeted to your interests.\n\na lot of people don't want to do that though because it costs extra money to keep advertising to people over and over. however, it's worth it.\n\nsource: i'm an internet marketer\n\nget ublock origin to avoid most of this.\n\nedit: so i got a lot of questions asking what a tracking pixel is.\n\nbasically, it's a piece of javascript code that executes once a page loads. the code it runs sends data about your cookies (which are saved on your computer to save web history) to a server, where this information is recorded. this information is used to tell a server that you, at that address, with that login, visited the page. then the pixel loads, and it's just a 1x1 blank GIF file.\n\nthis information is used to create audiences, which are just groups of people who have landed on a pixel. facebook makes it easy to send these audiences ads. google goes one step further than simply tracking traffic, though: google tracks nearly everything. \n\nthe only way to effectively avoid it is to (1) not have a google or facebook account and (2) always browse in incognito.",
"1) Because people sign up to those things.\n2) Lots of people.\n3) Because it makes money.\n4) No.",
"The popup is controlled by a cookie that prevents it from reappearing every time you open a new page on the site, but it expires after a while to have the popup reappear tomorrow. If you're using Firefox, the [Firebug](_URL_0_) developer tool can modify cookies. If you get a popup, look for the cookie in Firebug and set the expiry to a few thousand years in the future. Only works on the current site, but if you frequent it you shouldn't see the popup again unless they make a new one using a new cookie.\n\nAlternatively, you can use the eyedropped in uBlock origin to select the popup and block it by the top element, eg \"###mrLightbox_19h459s\" and delete everything behind the ' > 's in the text field that appears. This too only works on the current site.",
"I kinda like them because I know at some point the site administrator is going to go through the list of undeliverable spam and see my entered e-mail address, telling him what I think of his mother at where to stick his pop-ups.. Dot com.",
"As for a bit of understanding into why this is a thing, I might be able to shed some insight. If you see this type of thing on a relatively popular website, chances are it's a result of A/B testing. \n\nSay you sell cookies at a stand. You want to sell as many cookies as you can because more money means a new pushbike that you can't wait to have. Now, let's say you have many ideas on how to improve sales, like a glass cookie jar that people can see through and see your nom cookies (but the cookies get stale faster), and an opaque jar where the cookies can't be seen but they remain fresher for longer. Which one entices more people to buy cookies from you? Well, let's measure it!\n\nUse the glass jar first, and for every 100 people that pass your stand, count how many sales you get. Same with the opaque jar. If more people buy from the glass jar, then that's obviously better for your bike fund than the opaque jar. Who cares if the cookies are not as good; we're all humans and we'd rather have more money than giving people a better experience. \n\nSame thing with these doggone popups. They annoy everyone (including the people who implemented them), but they've been measured to be better for business, so they go up and stay up. More popular websites will measure this and prove its better for business, and small blogs and websites will blindly copy them. I'm hoping it's a \"phase\" the Internet will grow out of when it becomes less effective, but only time will tell.",
"I've signed up for more newsletters and emailing offers on sites that haven't shoved them in my face than I have from any site that has showed a full screen \"Sign up now!\" Ad. ",
"LPT: If you use google chrome you can right click > Inspect hover your mouse over the html that is causing the blockup (it should highlight in blue with a surrounding orange) and hit delete. It will remove the block so you can continue reading.",
"I once delved into this for a site I was building. Statistically, it is a far superior way to collect emails. It's creates a terrible user experience though too. ",
"Some sites use a cookie to see how many times in a certain amount of time you've visited the site and only show the newsletter after a certain point. ",
"Honestly, because it works - in the short run. I've worked for companies that have that on their website, and it's the most infuriating part of the job for me. It probably doesn't work on _you_, it certainly doesn't work on _me_, but there seems to be some not-trivial amount of people (our stats say generally older women) who will fill out forms because they're there.\n\nNow, the stats never tell the whole story, I'm pretty convinced it drives other people away, is bad branding, etc which will overall drag on our visit and conversion rates. But the middle manager who is on the hook to deliver business month to month, all they care about is the fact that if they make the annoying box go away, they'll get $n less leads this month. Instead, when overall numbers slowly dip due to the shitty user experience, they'll ask for increasingly larger and more annoying hoverboxes, because in the short run that will make up the difference. Meanwhile, we're still bleeding business slowly because we're annoying the piss out of our user base. But, the middle manager hit their numbers.",
"Actually I believe the reason for all the popups is to get Google ranking up. Google ranks pages according to how much time viewer spends on the page, but only AFTER the click on something. If the viewer only views the page, without taking any other action, such as a click, in Google's eyes the page was not interesting enough and it will rank it down. SEO people solve the problem by sticking something annoying on the page, in front of our eyes, just so they get us to click on it. That is all they want, if you sign up that is a bonus for them. Anyway, I hope Google changes the way they rank the pages, because the pop ups are becoming really overwhelming. \n\n",
"You know how mom and dad complain about getting junk mail. How they get a new credit card in the mail and say, \"why do they keep sending me this stuff?\" It is because it works. They only need a small number of people to signup in order justify doing it. Same thing with pop ups. Until it stops working they will keep doing it. \n\n",
"I personally like NoScript. It disables ALL scripting, which pretty much kills all websites from doing funky stuff like that.\n\nYou can whitelist sites you do use, and then they will work fine.\n\nYou can also temporarily allow a site.\n\nAs a bonus, this will block a lot of advertisements across all the sites you visit.",
"With *uBlock Origin*, you can block 3rd-party scripts and that will take care of most sites:\n\n_URL_0_\n\nHowever some assholes put their pop-ups in 1st-party scripts, so you would need to block those too. However I would avoid blocking 1st-party scripts if possible because it will break almost every site you visit until you build your whitelist.",
"They're called pop up ads. \n\nBack in an age called bronze by some, when walled gardens were king, a technique was born and thus it was that this technique was called the Pop up ad. The peasants did the opposite of rejoice for they sweated this technique. \n\nBut the wheel of time turns and ages come and go. There came to be a time called silver by some, when browser technology advanced and gave people the ability to stop/prevent/block pop up ads. The websites wept. For they lost a valuable source of their chicanery.\n\nThen came a [new technique](_URL_0_) in a new age called golden by none. Low and behold were born the in-browser pop up ads. And verily was this new technique effective at recreating pop up ads of the silver age without the blockability. It is here that we find ourselves. With tools that unlike water attacks on a fire pokemon are not super effective. ",
"I have no idea why some people think it's still a good idea. I'm currently building our companies e-commerce website, and one of the old guys (part owner) wanted me to put one of those. I refused. Functionality and user friendliness is the end all and be all. Anything that interferes with that is unacceptable. Perhaps it works for old people or something, but because 60% of our traffic is internet savvy 25 to 35 year olds, it's only going to turn them away. Luckily we have a loyal user base that is very active and gives us feed back at the slightest thing that pisses them off, which helps big time. We own the website, but it's not really OUR website after all, it's theirs, they are the ones using it. Aside from using a popup blocker, you can always try to voice your opinion and give them your feedback, and cut it out at the root. You'd be surprised. I messaged the website ebaumsworld one time. It was absolutely infuriating that they had a still picture thumbnail for a video that did not come from the video at all. They would put a high quality picture of something related to the video to make the front page look better. I told them it was wrong, and created a deceptive experience. We argued about it through emails, but eventually they told me they'd reconsider. Not only did I get a package of their website memorabilia in the mail, they changed the website back to actual thumbnails of the video shortly after. Maybe other people complained to, but at least I know I contributed. ",
"Because it works. Internet marketers have found that, over time, email subscribers convert (buy their product) more than any other form of marketing. So they ask for you email address for a \"free\" ebook. They ask for your email address when you get to the site. They ask for it when you leave the site. \n\nThen they keep sending you emails. Yeah, you'll ignore many of the emails. But someday they'll send you an email that entices you to buy something. That's why services like Mailchimp and Infusionsoft are so popular among internet entrepreneurs, they allow you to automate email lists.",
"Why? Usually because they don't have a good marketing strategy. They read or heard (misheard?) somewhere that someone did this and so they do it too. But they do it wrong. And then they have no idea why it doesn't work. ",
"I don't know because there is some \"big name\" site that sells housewares and maybe clothes. I see it advertised all the time. I think I've even seen commercials for it. It has one of those pages that requires you to give up your email address before you can see anything at the site. You can't even kill the pop-up. You literally *have* to give them your email to go any further.\n\nOh well, I've never gotten to see their site because screw that. I can't even remember the name of their site. FAIL FAIL FAIL FAIL.",
"as a former email marketer, i can tell you that they do this because it works. they get more signups than complaints. if they see a high abandonment rate (people leaving the website very quickly) they will remove the popup or alter the timing. ",
"This combined with not being able to save pictures from half the cool websites online due to overlays and webp formats... ARGH! The internet is becoming unusable some days. Combine that with MASSIVE amounts of trackers, weird repetitive ads with pictures designed to hack your mind and slideshows that don't start or only have more ads... \n\nGive me back homemade geocities websites. For real.\n\n",
"Because they're run by idiots who confuse offline interruption marketing with online permission marketing. Online you're ferociously task orientated and anything that gets in your way will annoy you.\n\nJust boycott the site and the company and (we can hope) these idiots will eventually go away.\n",
"install \"ublock origin\", then right click, choose \"block element\". it might take 2 or 3 tries but it can do things like browse pinterest w/o logging in",
"I know what you mean and i believe personally its terrible. I believe in time this trend will fade into the classification of bad practice. Designers know that interruptions are a big no-no in the flow of things. You don't want slow loading content, bad connections, NO OBSTRUCTIONS BETWEEN THE USER AND THE CONTENT - is generally a rule to reach for.\n\nThese pop-up lightboxes; especially the delayed ones are obstructions and i don't know when or why they are currently implemented. It reminds me of a time when tiny type, and multimedia was the major practice (around the myspace times). the web is developing into full usability. practices come and go en masse. the interruptions are annoying and unfortunately well established for the time being."
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4cj937 | if the student loan bubble is so certain to happen, why is nobody attempting to bet against the student loan market as in the movie the big short? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4cj937/eli5_if_the_student_loan_bubble_is_so_certain_to/ | {
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"Shorting is generally very risky. You can't just know that a bubble is going to pop, you need to know when it pops. If you invest in the short too early, you might need to close it before the bubble pops and end up down\n\nFor example, say there's a drug company Magic Industries. Magic Industries says they are going to cure cancer, and that it's in testing, and they generate a lot of hype. Their stock price keeps rising and rising. You are a scientist, and you are sure that they are lying, and their entire company is worthless. However, if you go short now, and the company keeps rising, you lose money when you close it. If it collapses after you close the short position, you end up losing money, even though you were right. You need to know exactly when the stock will crash in order to place the short and then close it over the time when the bubble pops\n\nedit: Explanation of shorting:\n\nShorting is essentially betting against a stock or security. Basically, you borrow it from somebody else (for a fee), sell the borrowed shares, and buy them back after their price goes down, for a profit.\n\nFor example, say I'm sure Magic Industries stock is going to crash. I pay James $100 to borrow his 100 shares, currently valued at $10 each. I sell those shares for $1000. Then Magic Industries crashes, and I am able to buy back those 100 shares for $5 each. I give those 100 shares back to James.\n\nI spent $100, but then sold the shares for $1000 and bought them back for $500, so I profited $400.\n\nThe problem is that when I borrowed the stock initially, we agreed on the length of time I was allowed to wait before paying him back (closing the short). If the stock actually went up to $15 per share, I would have lost $600.\n\nI can't really simplify it any further",
"People may be betting against it and we just don't know they are. Also, I may be wrong, but federal student loans are held by the United States government, so when it does collapse the outcomes will be greatly different than privately held junk mortgages. When the housing bubble burst, we had to bail out the banks and many companies filed for bankruptcy. If the student loan bubble bursts, the outcome will be very different. Will the govt even let it burst? They can artificially prop it up for decades because of the practically unlimited money the govt has. ",
"Strictly speaking, there are no securities that one could trade that would accurately represent a short position against student loan debt. Indirectly, one could short the stocks of banks that issue private loans, or one could short treasury futures if they thought less of the full faith and credit of the US Gov't.\n\nedit: Apparently, I'm wrong. It seems SLABS and Navient stock would be appropriate methods of shorting the student loan market",
"It's not really that possible since the loans are held by the government. Private loans could be shorted butnyou.might as well short the entitity holding them if that is their primary business.",
"There is no such thing as a \"student loan bubble\", that's just wrong terminology used by people who think anything that seems to go up in price to a degree they deem unreasonable must be a \"bubble\".\n\nA bubble is when asset prices are driven by speculation, by people willing to pay any price because they think the price can only go up and they want to resell the asset at a higher price.\n\nDegrees are not resellable, and \"buying\" them takes years and involves a lot of non-delegatable work. And I also don't see the loans themselves being traded around.\n\nSo whatever is happening, it is not a bubble, and you can't bet against it in the same sense.\n\n**Update:** Someone has pointed out that the loans *are* traded (\"SLABs\") and there may be characteristics of a bubble there. But there is still a limiting factor in that the *number* of student loans is limited pretty tightly by the number of people who are students.",
"The student loan bubble is quite different to the real estate bubble depicted in The Big Short, and quite different from most other bubble's we've seen. The main reason for this is that the student loan bubble has not been created and sustained by private institutions but by the government itself as it is by far the largest student loan lender.\n\nThe specific part that sets this debt apart from the debt of the real estate bubble is the way it's packaged and re-sold. The real estate debt was securitized and packaged largely in Mortgage-Backed Securities which bade it easy to discern which securities and which institutions to short. On the other hand, student loan debt is lumped in with all the other types of federal government debt and sold as the different Treasury notes; that makes student loan debt indistinguishable from other federal debt.\n\nSo, if you want to take a short position on student loan debt, you either have to look to the private lenders which are a much smaller piece of the pie or you have to *short the US government as a whole*. Neither of those is a particularly good idea.\n\nMost student loans are not dis-chargeable through bankruptcy so the government will be in the drivers seat when the bubble pops. Since the debtors are unable to discharge this debt, the government has no incentive to forgive the debt and incur large losses. While the popping of this bubble has the same potential for disaster as the real estate bubble, simply changing the terms of distressed loans (lowering rates, new opportunities for forbearance, extending repayment periods) may be all that's needed to alleviate the worst effect. If the government's treatment of homeowners vs its' treatment of Wall Street is any indication, the least amount possible will be done to help debtors to ensure the government gets its' money.\n\nTL;DR - Because it was possible to short JUST real estate debt, but it's not possible to short just federal student loan debt.\n\n",
"There are some publicly traded co.s that deal in these loans like Navient. I'm not sure what the short interest is, but they pay a hefty yield and when you short you'd have to pay that as well. It's also not certain that this bubble, backed by the government, will implode. Clinton has a plan to ease the interest rates on these loans. My guess is a soft landing via gov intervention. Also, I think the price of secondary education is going to be affected by online learning in the next ten years. ",
"Sallie Mae, for-profit colleges, and First Marblehead got tagged hard years ago.\n\nTruly dumb buyers of student loans have not emerged. The securitization markets have not recovered anywhere near their former level of froth. I don't think people are even doing securitizations of private student loans any more; the fundamental driving force is missing.\n\nStudent loans aren't a bubble. Arguably the suckers are the *sellers* (i.e. the borrowers) rather than buyers, and the smart guys are on the long side of the trade... although it's not really that exciting.\n\nThe long, high inflation of college tuition is ultimately unsustainable, but I fear we've got a long runway. There's a long line of people in China who would be willing to pay more than current tuition rates for a spot at any of the top 100 American universities if they can't squeeze by the entrance exams at Peking University or Qinghua University.\n\nA large abundance of high-quality tertiary education available relatively cheaply... which is what America had for a long time... is also ultimately unsustainable, if there's competition in a global market. Basically, a kind of indentured servitude is developing. I don't see a whole lot changing fast unless we lose our expectation that everybody needs to go to college.",
"Along with everything else written t he market is different in that if I short the real estate market by either the marketization or by getting into liquid assets such as cash or government bonds, when the bubble does burst I can buy real estate for pennies of what it's worth... If a student loan bubble ever popped... I can't get anything for a cheap/good deal, so what is my incentive to short it? ",
"What product would you use to short the student loans?",
"Who says the student loan bubble is certain to happen? ",
"I'm a 23 year old recent graduate with ~$35,000 in student loans. I'm planning on paying them off over a ten year period. Should the existence of this student loan bubble affect the way that I pay them back?",
"I also really hate that people are constantly quoting this movie now as if they understand finance and the crisis. I hate pop culture and all its circle jerk stupidity ",
"Because there aren't any means available to \"short\" the student loan bubble as directly as say the housing bubble. Back in 2007/8 you could use derivatives to easily short MBS and other combined loan products.\n\nStudent loans aren't packaged up like this at all. Most are federally backed which means the government holds them. Private investors do not have access to these. Secondly, unlike the housing market which went bust from bad loans, student loans cannot be discharged in bankruptcy. The federal government then will go and use your social security to pay back the loans at a future date. Don't think for one second they wouldn't use defunct student loans to deny future benefits payouts especially with a $20 trillion dollar debt hole. \n\nGranted you can short businesses that profit from the student loan bubble. Things like for-profit colleges and education supply companies (publishers, etc) are easy targets. However you would not make as much money as the folks in the big short did. \n\nMost of the people who benefit from the student loan bubble are non \"profit\" colleges and universities. They will definitely be hurt when the bubble pops but there isn't a way to short these institutions. ",
"There is a lot of student debt out there, $1T, but it pales in comparison to the mortgage market which is close to $15T. So the opportunity for betting against student loan debt is much smaller. Student loan debt is tricky because it generally cannot be discharged in bankruptcy whereas a mortgage obligation could be. If you default on your mortgage payments the bank can repossess your house. If you default on your student loan payments they can't exactly repossess your soul. You're just stuck paying for school...forever. \n\nInvestors have bet against and it started with the for-profit college sector. Several publicly traded for-profit colleges have already gone under and many more no longer trade anywhere near their historical highs. E.g. Apollo -82% over 5 yrs Devry -67% over 5 yrs\n\nThe public has slowly learned that degrees from these so-called institutions are worth pennies what they paid. It's hard to make money when your enrollment declines every single semester. \n\nI don't think there is anything wrong with for-profit schools, many daycares are for-profit, but they need to be held to much higher standards than they are currently. ",
"Crap mortgages and student loans - how to annihilate your middle class in two easy, myopic steps.",
"Don't short it, buy for long term when it crashes.\n\nSoooo 2008 when the market last crashed I grabbed tons of GE.\n\nShorting is crazy unless you love risk, it's just gambling to me...\n\nSo like 5...\n\nYou know how that candy is really expensive now? Wait till it's really cheap and buy enough to last years! \n\nAnd don't bet on things! Betting is bad!",
"Lots of people know about things that are going to happen. Nobody knows when things are going to happen. Timing is everything since shorting strategies always have a timeline.",
"There is no \"student loan bubble\" and there is no student loan market for you to short. \n\nStudent loans are provided by the government, so they don't depend on investors backing them, which is how bubbles actually happen - a part of the market has lots of investors putting money in on speculation, and they all pull it out at the same time when a crisis hits. \n\nBy the same token, student loans are not in any kind of massive crisis. A lot of individuals are having trouble repaying them because of the job market, [but because of loan forgiveness programs it's a pain for them, but not a disaster](_URL_0_). \n\nIf you want to \"go short\" on some part of the education market, do it with the private for-profit schools. Those are a disaster in the making, and they are mainly responsible for almost all the students having trouble repaying loans. ",
"Sallie Mae 10 yr debt is yielding ~12%, Both S & P and Moodys have it rated as junk. 12%/ yr, every year is a very sweet return. What's interesting is the company makes A TON of money, has extremely wide margins, and has a generally clean balance sheet, so if their current financial look good, why the junk rating on their bonds? Well my guess is the debt markets are calling bull shit on the sustainability of the student loan market. A lot of people that work in finance will tell you the bond market is \"smarter\" than the equity market, that is to say, it's a kind of leading indicator. \n\nHere's something that will make you angry; SLM's operating margin is 56%. A lot of folks tend to think most companies rake in money and generally screw their customers. Not so much case. Temper Pedic, (I've seen the Reddit debate that mattress companies rule the world and up charge ~300%) operates at a 10% profit margin. GE, Apple, Goldman Sachs, Boeing, Nike, all have operating margins that range anywhere from about half to a fifth of SLM. ",
"Because it’s not “certain to happen.” It’s a widely debated topic. \n\nFor one, the earnings premium for a college degree is higher than it has ever been before, and it continues to increase. ([source](_URL_1_)) \n\nWhereas in 1980 college graduates only make 40% more than non-grads, today the number is around 85%. ([source](_URL_0_)).\n\nThe ROI for college is higher than the stock market, bonds, real estate, and private equity. Unlike housing, a college degree’s increase in value over the years is very real and substantiated by data. This is the opposite of a bubble. \n\n\nThe phrasing you used in the title shows confusion about what a bubble is. Nobody is saying \"it's going to happen,\" they're saying it exists and it's going to pop. \n\nWith a house, there’s an actual tangible asset that can reduce in market price very quickly when there’s an abrupt selling of houses. With higher education, there is nothing to be sold, so making a comparison between housing and student loans is misleading. \n\nWhile it might be sort of similar if many people defaulted on their loans at the same time and tax payers had to bail them out, this is not what is occurring. Even if it did, people would still have their degrees (unlike defaulting on a mortgage where your house gets taken). In fact, default rates have declined since the late 80s/early 90s. ([source](_URL_2_)) Most people end up paying their loans, many times over throughout their lives, and benefit greatly from having a degree. \n\nAnd even if they didn’t, there still is very much “consumption” value in college, in the form of intellectual growth, social experience, etc. This would be impossible to repossess as well. \n\nIn summary, college degrees are highly valuable and that doesn't seem likely to change anytime soon. \n\n",
"Notice that all the answers that say there isn't a bubble, which is true, are at the top of controversial. Welcome to Reddit. Where people come to hear what they already believe, and bitch with people who are educated on something. \n\nBernie 2016!!!",
"There is a saying in the markets \"the market can stay irrational much longer than you can stay liquid\"\n\nInvestment strategies cost money. There are doubtless lots of investors trying to make money off this bubble. When it collapses, some will, and maybe they'll make a movie about them",
"The largest reason is that student loans are currently originated mainly by the federal government. The federal government doesn't sell off these loans to be securitized as mortgage originators do. The government simply holds on to them. If the student loans don't get paid back then the government loses. There just isn't anything to bet against as there was in the mortgage market where people were able to bet against the certain tranches of the securitizations.\n\nIt is true that until 2010, private lenders did originate federal student loans under the FFELP program, and while these loans have been securitized, the federal government still guarantees 97-98% of the principal for these loans. There are lots of securitizations of these FFELP loans that exist now, created mainly by Sallie Mae (now Navient) or Nelnet. But because of the federal guarantee, there just isn't much downside to any of this.\n\nThat said, private student loans are currently originated by private lenders and these do not have any federal guarantee. These loans also have been, and continue to be, securitized. The numbers here are small though, insignificant compared to the size of the subprime mortgage market leading up to the bursting of the real estate bubble. For example, Navient (the largest securitizer of student loans) securitized $1.7 billion of private student loans during 2015, a very small number in context. In addition, these private loan securitizations now are being built in a less risky way than the subprime mortgage securitizations were. A clear example there is the overcollateralization % - the measure of the amount of assets in the securitization trust compared to the amount of investment securities sold to investors, can be compared to a downpayment on a house -- is running around 20% for current Navient private loan securitizations, while this was low single digits for subprime securitizations during the bubble.\n\nSo the answer is that the vast majority of student loans that have been made and student loans that have been securitized, are 97%-98% guaranteed by the federal government and therefore don't carry much risk. Riskier, unguaranteed private student loans have been made and have been securitized and sold to investors, but they aren't as bad as the subprime securitizations were during the bubble, and the numbers are much, much smaller. The student loan market just can't be bet against in the same way or in the same magnitude as the mortgage market could be.\n\n",
"Not the same market. Big short was tied to housing assets. Student loan there is no marketable asset to fail. College is an investment - what you do with it is only up to you. With a house there is a marketplace that says what it is worth.",
"This post is not about the policy behind student loans and I am not saying that the student loan bubble is not a huge problem. But it is different from the housing bubble. \n\n-\n\nStudent loans are not secured by any asset like property is with a mortgage loan. Sure the property can greatly diminish in value and it has carrying costs but it has some value in the event of default/foreclosure. Student loans are not secured but they're not dischargeable in bankruptcy (short of extreme undue hardship). The mortgage loan is dischargeable in bankruptcy. So a mortgage debtor can attempt to have a new start but not so fast with those student loans.\n\n-\n\nSo you have this student loan that runs with the life of the student until it is paid off. These loans can grow and grow and the likelihood of being paid off may decrease but they're not leaving the debtor. The value of these student loans, for the creditor, is in the potential earning power and safety (they're not dischargeable).\n\n-\n\nAlso what would a major default look like in student loans? A ton of student debtors stop paying their loans? Remember that even if they stop paying the creditors have ways to go after them. We know what the housing bubble looked like already too.\n\n-\n\nThe next question is knowing these loans are not dischargeable, how would you go about shorting them or betting against them? The majority of debt is held by Uncle Sam. So I am not sure of the natural investment that exists. How would you short Sallie Mae?\n\n",
"Every bubble is certain to happen. We know that the market will crash again, in order to short something, you need to know the exact timing. This is where it's difficult, and this is why shorting is very risky. You are betting against the current trends in the hopes that prices will fall dramatically.\n\nAn ELI5 example would be:\n\nYour neighbor has a house that's vacant, and he's just holding on to it for a few years until he's ready to sell. You rent the house from your neighbor for 6 months. Immediately, you sell it for $500k (the market rate at that time). In 6 months, you must buy the house back at its current market rate and return it to your neighbor and pay them for the rental period.\n\nA successful short means that in 6 months, you buy the house back for $200k and then return it to your neighbor, meaning that you pocket $300k. An unsuccessful short would mean the the price of the house has stayed the same or gone up, meaning that you either make $0, or you end up having to dig into your own funds to pay the difference.\n\nThe key is knowing how long to lease it for."
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"http://chronicle.com/blogs/innovations/job-skill-trendsthe-college-wage-premium/27091",
"http://phys.org/news/2011-09-student-loan-default.html"
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f5nl2b | how do you gauge audio quality just by hearing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f5nl2b/eli5_how_do_you_gauge_audio_quality_just_by/ | {
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"Good speakers just sound better. Clear pure highs, low rumbly lows, good strong mids. You’ll especially notice it in how you’ll hear instruments you missed on bad speakers. Default speakers often don’t even have a subwoofer, so all the bass is coming out the mids, this makes them dull, flat and lifeless. \n\nMovies are great for this. Watch something with basic included speakers in your tv. Then plug in THX Dolby speakers, even just a two speaker + sub woofer basic kit, like decent computer speakers kinda thing, never mind a proper 5+ piece rig. It’ll blow your mind."
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82m39i | why do baby's have their fists clenched all the time? | I just recently was introduced to my newborn first cousin once removed, and I noticed that her fists were almost always closed. Why is it that babies always clench their fists? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/82m39i/eli5_why_do_babys_have_their_fists_clenched_all/ | {
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"Instinct reflex.\n\nIt goes out after some time, but it’s an inborn reflex for not letting go",
"It is the grasping reflex that we share with the other apes and many primates. It is important for the infant to be able to cling to the mother or tree limbs, and even though we have lost fur and no longer live in trees that instinct has remained. "
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2qf8f1 | how do video game cheat code devices (action replay / gameshark) work? | What exactly does the device do to create a cheat code environment? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qf8f1/eli5_how_do_video_game_cheat_code_devices_action/ | {
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"Games (and any software) will load elements that it needs to use into the device's memory. These cheat devices find where that piece of code lives in memory and modifies it. So basically it looks in memory for where your number of lives are stored and changes it to whatever you tell it to. In the case of setting something to unlimited the cheat device prevents the game from changing what is stored in memory. ",
"In addition to /u/wcrb15's answer, I'd also add that just like modern PC games have built-in functions meant for the use of devs during the game's creation and testing, older games often had these as well. So, if the GameShark programmers knew how to activate a specific developer feature (like \"god mode\" so the dev doesn't get killed while testing the boss he's debugging), they would include that in their product as well.",
"The most basic type of code you would program into the device is a RAM Overwrite code. The simplest example of this would be an infinite money cheat. The developers working for AR or Gameshark load up the game on whatever developer hardware they have and play for a bit. Eventually, they would take a note of how much money the game says they have, and also take a snapshot of the contents of RAM. Then they could go buy some stuff and take another snapshot. At this point, they could do a search through the RAM snapshot for the value of money that the game showed when it was taken (say $1000). This would give them all the RAM locations containing the value 1000. Doing the same for the second snapshot, they would get all the locations containing 800 (for example). A simple cross-reference should yield the locations in RAM that contain a reference to the value of money the player currently has. If there's a lot of results, more snapshots would help narrow it down.\n\nIf there are still multiple results after several snapshots are correlated, it probably means that the value for money is stored in multiple locations. This could be because one is a \"saved\" value and one is a \"working\" value, or, the value is copied at some point for computation, but not overwritten with something else when the computation is done, or the game has some sort of error checking system where all the values must match. At this point, the cheat developer would start playing around with what happens when the values are manually changed.\n\nOnce they figure out which RAM locations actually control the value of money, they take those locations, along with some value (say 9999 for example), and make a RAM Overwrite code. When you program this code into your cheat device, it instructs the device to periodically (many, many times per second) overwrite whatever value is in those RAM locations with 9999. So, when the player goes to buy something, the new value of money is calculated for the purchase, but shortly afterwards, the cheat device rewrites the value as if it never happened.\n\nThe code itself that you program into the cheat device just contains some value indicating the type of code (RAM Overwrite in our above example) the RAM address to overwrite and the value to write with. Also, most companies will take the code and encrypt it so that only the cheat device can decrypt it and figure out what the code is supposed to do. This just protects the work they put into developing the cheat.\n\nAnother important type of code is the Enable code, and is a bit tougher. With most cheat devices, you have to have an enable code to use any other cheats for the game. This ties into our above example where we talked about RAM locations being overwritten many times per second. Doing this is actually not that simple. The cheat device doesn't have access to RAM at all, not while the game is running. The only thing it can do is, when a request is made to get read-only data from the cartridge (code to be executed, graphical data, audio data, etc.) the cheat device can intercept it and send something else instead.\n\nTo get access to RAM, the cheat device needs a hook, a mechanism by which it can begin inserting its own executable code into the game code. To do this, the cheat developer needs to find some spot in the game code to insert the hook, which will probably involve replacing some game instruction (or several) with another instruction (or several) that will attempt to access the cartridge in some way that the cheat device will recognize. This can only be done with expertise, as finding a good hook point involves finding some game code that is run very frequently, that can be modified without breaking the game, and that can handle being halted for significant periods of time (while the cheat device runs its code) without affecting the performance or responsiveness of the game. For example, the cheat developer could use a section of code that checks the status of the controller buttons, to see if any have been pressed, which pretty much every game needs. This gets run very often, but messing with it could affect the game's responsiveness to button presses, and the player might feel that the game is laggy.\n\nThe Enable code itself will contain the following. (A) Information for the hook instruction(s) such that during any normal cartridge read, if the hook instruction is part of the read, the cheat device will automatically swap the game's instruction out for the hook instruction and send it instead. (B) Optionally, as this may not need to be different from game-to-game, information about what \"special operation\" the hook instruction will perform, which signals to the cheat device that it needs to start sending its own executable code to be run. (C) Optionally, information about where the cheat device's code will be loaded into RAM. Running from RAM as opposed to ROM is much, much faster, and less likely to cause \"lag\" issues as described above, but requires that there be enough space in RAM to load all the code, without affecting the game. (D) Optionally, information about the instructions that the hook replaced, which may still need to be executed in some way.\n\nAgain, this is still a pretty basic picture of the kinds of things cheat devices do. All of the above assumes, for example, that the game doesn't contain any type of anti-cheat measures. The Pokemon series is probably the most famous for anti-cheat. Individual Pokemon that you've caught are made up of 100-byte blocks of memory (in Gen 3, more bytes are used in later Gens) most of which are encrypted and checksummed. Additionally, the actual locations of the blocks in the cartridge flash memory varies, and the entire contents of flash memory are checksummed, preventing any changes from being made without also changing the checksum value. The encryptions and checksums are not that complicated and are actually pretty well documented and easy to fake for developers and people with special hardware, or emulators, but doing so from a cheat device that has to rely on hooks and limited access to RAM is pretty damn difficult.",
"The most basic explanation I can think of is that cheat devices are memory editors. If you look at devices for the PlayStation, or Code Breaker for the PS2, it is easiest to see, as those codes are unencrypted. Starting around the time of PS2, companies like Datel started encrypting their codes because of competing cheat devices.\n\nCodes generally contain a condition, a memory address, and a value. They can say \"always keep this memory address at this value\", or \"when this address is this value, change that address to that value\" (AKA, when this button combination is held down, make the code active, or add something to a value). Since game consoles are identical to each other, unlike computers, a program running on a game console will always have the same variable in the same place. This makes it easy to have universal codes.\n\nEnable codes on encrypted cheat devices are really just providing a decryption key for the rest of the codes. Unencryptead cheat devices don't need them.\n\nThere are programs for Windows, like CheatEngine\" that do the same thing as a console cheat device, but you have to wrok at finding memory values yourself, because a lot of computer operating systems now randomize the address space of a program to prevent malware from reading data out of the software."
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b6t81b | how does the electrical grid, respond so quickly to power being turned on/off all the time all over the place, if they generate just enough power in real-time for the demand? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b6t81b/eli5_how_does_the_electrical_grid_respond_so/ | {
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"although they can only provide enough to meet demand (at least until big battery banks become a thing), they are rarely running at 100%.\n\ne.g. you might have 2 generators each able to punch out 100MW, but if demand is only 160MW then each of them will be running at about 80% load. The remaining 40MW is known as \"spinning Reserve\" (at least where I am, sometimes called \"operating reserve\" elsewhere) and is immediately available to handle those transient load changes \n\nyou might also have a 3rd 20MW generator (imaginatively termed \"non-spinning\" reserve) which is a quick start, but generally smaller capacity generator built to provide a boost to the online generators when the spinning reserve is about to be exceeded.\n\nyou might even have a 4th (or more) 100MW generator on \"contingency\" reserve - these are generally slower to start up, and not very quick to respond to power spikes, and are more there for planned maintenance redundancy, or when the power plant \"knows\" it will have a long/medium length increase in demand (e.g. 5pm during summer when everyone gets home and turns on the airconditioning)\n",
"On the timescale of seconds, it's an automatic consequence of how generators work. On longer timeframes, the power stations are manually or computer-controlled.\n\nEvery generator has a lot of weight spinning at high speed, so it stores a fair amount of kinetic energy. When there's no demand for power, the generator produces a voltage but no current flows through its coils. When you turn on a light switch, current starts to flow through the generator, creating a magnetic force that *slows down its spin*, changing energy from spinning kinetic energy to electrical.\n\nAs users draw more and more electrical energy, the generator will spin slower and slower, until a person or computer at the power plant notices and \"steps on the gas\", adding fuel or steam to the turbine that powers the generator, bringing it back up to speed.",
"Voltage can vary within a range of +/- 5% (at least in the US). Some of that is due to the changing of the power grid load, as demand rises, voltage sags, until the control systems notice the sag and increase fuel to the generators. Pure resistive loads (like heaters or incandescent bulbs) will also eat less power during that time. The converse is also true, as demand drops, voltage rises, and the control systems cut fuel, and pure resistive loads will eat more power. \n\nRealistically, it needs a lot of load being added or shed at the same time before it causes big changes to the generators.",
"Many of the generators in the grid are \"synchronous\" generators, which are driven by some sort of engine. \n\nWhen multiple synchronous generators are connected to the same grid, then they become \"locked\" together - all turning at the same speed. In the US, this is 3600 rpm (60 Hz), but in other parts of the world this is 3000 rpm (50 Hz).\n\nGenerators have the property that as you draw more power from them, they become stiffer to turn. So, there is a simple way of controlling them, called \"frequency control\". The speed is monitored, and if they are going too slow, then the engine is turned up; if they are going too fast, the engine is turned down.\n\nThis is how the grid is controlled on a second-by-second and minute by minute basis. This is possible, because all the rotating synchronous generators spinning at high speed, have a lot of inertia. This means that when there is a sudden increase in power consumption, the frequency drops slowly over about 10-30 seconds. This gives plenty of time for the governors on the engines to detect the change in frequency and adjust the fuel supply. \n\nThe grid manager will make sure that there are enough power plants running at partial power, and in automatic frequency control mode to handle any unexpected problems.\n\nHowever, for expected deviations, are more efficient plan can be used. Plants can be used as \"spinning reserve\". They can be running, but not at full power. However, the power plant and the grid manager can agree, that the grid manager can request additional power at short notice. \n\nFor longer and planned deviations, the grid manager might tell plants that their power is not needed, and they can switch off for the night, or for the weekend. The job of the grid manager is to have enough plants available to provide spinning reserve, and frequency control; but not keep too many plants online and idling when it isn't needed. However, turning a plant off may mean it takes a long time to switch on again - it can take 4-6 hours to start up a coal plant, or 30-60 minutes to start up and warm up a large gas plant.\n\nDifferent power plants with different engine designs, might have different response speed, so they do different things. For example, hydro plants when in standby mode, can respond to a request for power in about 10 seconds. Other plants like gas, take a bit longer - maybe 2-3 minutes. \n\nSo, in the event of a sudden spike in demand, the first thing that happens is a drop in frequency; and then over the first 5 seconds, automatic frequency control kicks in. Then after about 1 minute, the grid operator may ask their fast reserve plants to take over, so take the strain off the frequency control plants (so that they are ready to handle the next spike). Then the slower reserve plants can take over for the next couple of hours, until the spike has passed.\n\nIf the spike is expected to last a longer time, or is very large, then there may be further levels of reserve. For example, diesel engines or fast starting gas turbine engines. Normally, these allow about 10-15 minutes to start up, warm up and synchronise with the grid; and these can run long enough to allow cheaper power plants to warm up and take over. "
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1d5914 | why is there men hair shampoo and women hair shampoo? is there a difference between men's hair and women's hair? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1d5914/eli5why_is_there_men_hair_shampoo_and_women_hair/ | {
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"Biologically, no, but there's a difference in what men and women WANT with their hair. Men's shampoo has to deal with dandruff, while keeping the hair \"rugged\" or \"rough\" in texture, whilst women's hair, in addition to being longer in length, must be soft and possess an elegant luster. \n\nAlso, women get to have delicious fruity shampoos because girlyness",
"Yeah, I think its just a fragrance thing. Men want to smell manlier, whilst women have flowery/fruity smells. I don't care about that though, I have some lovely blueberry shampoo that is not very manly but smells divine"
]
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[],
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||
17ghkz | the difference between shame and guilt | This is kinda out there, but I couldn't find a decent /r/ask_ sub :/
Anyway, I know that there are cultures labeled 'shame cultures' and 'guilt cultures' and I understand the difference between feeling shame and feeling guilt,
but I'm not sure of the *effects* that living in a shame vs guilt culture has on the way they act,
for instance, I've read that when the Americans and Japanese fought each other in wwii, there were very few japanese prisoners, as they felt death was preferable to the dishonour of surrender, whereas American prisoners were treated terribly by the Japanese for disgracing themselves with surrender.
So I'm just wondering if there is any set of 'rules' or easy way to understand the differences between how these different types of cultures interact. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/17ghkz/the_difference_between_shame_and_guilt/ | {
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"Shame is external, guilt is internal. Shame is focussing on other people/society/norms and the rule you have broken, whereas guilt has its focus on your own experience and what you feel about your action.",
"In the context you're using, I may be wrong, but I'm pretty sure I'm not. \nGuilt is when you feel bad. You stole from a friend, and you know its wrong. So you have a bad feeling in your stomach and it makes your whole body hurt. \nShame is when other people want you to feel bad, and thus you do too. You got caught stealing from your friend, and everyone is upset at you. You feel shame because it makes you look bad. \nI hope that helped somewhat. Also, one sub you may be interested in is /r/answers "
]
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[],
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|
99cn55 | why do people make noise when something/someone physically assaults them? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/99cn55/eli5_why_do_people_make_noise_when/ | {
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"Like, growls, screams, and cries? That's an animal instinct to either frighten the enemy or call for help. Useful stuff. Lots of animals don't ever cry or scream when in danger because they are not social animals. They don't hep each other. But we do."
]
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[]
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||
si9xr | when looking up the difinition of a word, how are we supposed to read the "pronunciation" text. | [Example](_URL_0_) how are we expected to read **ˈdikSHəˌnerē** and make it the pronunciation of Dictionary? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/si9xr/eli5_when_looking_up_the_difinition_of_a_word_how/ | {
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"text": [
"It's usually in [IPA](_URL_0_). This is a standardized system used for representing the sounds used in language. "
]
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"https://www.google.com/#hl=en&gs_nf=1&tok=QFhU6BzIPTZWXnR__nbiLA&pq=dictionary%20format&cp=15&gs_id=1o&xhr=t&q=define+dictionary&pf=p&safe=off&sclient=psy-ab&oq=define+dictiona&aq=0&aqi=g3g-s1&aql=&gs_l=&pbx=1&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.,cf.osb&fp=1db2448d0c59a407&biw=1920&bih=889"
] | [
[
"http://en.wikipedia.org/wiki/International_Phonetic_Alphabet"
]
] |
|
2mywso | why does a book in canada cost so much more than the same book in america? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2mywso/eli5_why_does_a_book_in_canada_cost_so_much_more/ | {
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"Senate report cites barriers at border for price gaps:\n_URL_0_",
"Also, as well as other posts: Taxes and tariffs. Both of which effect end prices, depending on the law and the good",
"It's because you are willing to pay that price. It's that simple."
]
} | [] | [] | [
[
"http://www.theglobeandmail.com/report-on-business/economy/senate-report-cites-barriers-at-border-for-price-gaps/article8296607/"
],
[],
[]
] |
||
32gjqx | what is the point of spam e-mails that don't have any links/advertisements, but rather just have nonsensical gibberish? how are scammers making money off these? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32gjqx/eli5what_is_the_point_of_spam_emails_that_dont/ | {
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"They can be used to check for valid email accounts or accounts that people actually use so that they can be further spammed.\n\nIf it's an invalid email account, it will be bounced by the mail server.\n\nThey can receive a \"read\" receipt by the reader. This allows the spammer to see that the someone is using that account. This is less common because you typically have to specify that you want to send a \"read\" receipt.\n\nOthers have an embedded image (as small as a small white dot) to a website that can track how many times it was viewed and from where. This is why many email programs initially block linked web images.\n\nEDIT: I'll add some more points that others have mentioned:\n\nThe gibberish can be used to disarm spam detection methods. If enough gibberish goes through, a spam account can be marked as not-spam or the spam filter will not care about a certain order of words.\n\nCombined with the other read detection abilities, spammers can see what type of emails will get past the spam filters. This is a way of reverse engineering the spam detection rules.",
"I also read that it is used to filter people they can scam.\n\nIf someone replies to that gibberish they're a lot more likely to send money or account details.\n\nIf it's a normal email and someone replies, it can be harder to scam them.\n\n_URL_0_\n\nIt does always amuse me to read through them haha. ",
"It's to degrade filtering. That is a mail that users mark as spam, but which doesn't contain the word \"Viagra\", so statistical filtering software gets less sure of its accuracy, and may let more spam pass in the future (typically you would configure some threshold, like \"throw it away if you are 95% sure\").",
"The top answer is good, but I think there is something missing. \n\nMost email services utilize machine learning to model incoming messages. Over time it gets really good at filtering out those in which it thinks are spam. Sending tons of gibberish emails could re-train a machine learning algorithm so that emails later on down the road that looked spam would now be passable. ",
"The emails can have \"hidden\", blank, and very small images that are hosted on the spammers servers or compromised computers from previous attacks. When you open the email, it automatically downloads the image while sending back to the spammer, that you email address is valid.\n\nThis is why, by default, email clients don't typically automatically download hosted images in an email, and you have to manually right-click a warning to get them.",
"I have a similar question. I am getting spam mails without HTML, any links, pictures, attachments or company names. They offer me jobs and ask for a reply. The mails come from all around the world.\n\nAfter getting about 50 of them I replied to one. Delivery failed.\n\nIs there still any use for the spammer here?",
"Make lets say 50,000 accounts with the most popular email providers (Google, Microsoft (hotmail, outlook) etc.)\n\nThen you sent **carefully** created emails, they might look like jibberish, but you don't care about the message, you're farming keywords - words that sends the mails directly to the spam folder.\n\nNow, add a list of emails you bought, let's say 300,000...\n\nYou won't click any of the links in the mail in \"your\" accounts, you juste want to see what went through -- but you also have let's say 0.2% of those 300,000 email recipients that do.\n\nThat is 6000 verified, workin emails.\n\nSo, not only do you farm the hosts for their filters, you just got 3000 workin emails to send the actual spam to.",
"The list of people who do reply would be potentially quite valuable. If you're dumb enough to reply to a gibberish email, you're probably dumb enough to be scammed more easily than the general population. ",
"I have a similar question in regards to these sort of emails, that doesn't require a \"like I'm five\" answer. By habit, I unsubscribe from nearly every email I receive if possible, including these weird spammy emails that have the huge gibberish blocks of text at the bottom. Am I doing the wrong thing by entering my email into their unsubscribe pages? Like, am I just inviting more spam into my box by confirming that the email exists?",
"Check out [Bayesian poisoning](_URL_0_). The \"gibberish\" emails or emails with a long passage from an old book are used to render a certain type of spam filter, a Bayesian filter, unusable as it \"learns\" to be less effective. This is not usually a very effective attack, as email administrators will normally have a number of different types of email filters in place. \n\nI've found that filtering based on strict adherence to DNS standards to be far more effective and less taxing on system resources anyway. You'll get rid of over 90% of the spam just by checking if the sending domains have MX records and reverse PTR's match the SMTP greeting. Bayesian filters should only be used after other filters have been used such as DNS and RBL's to reduce overhead. ",
"I'm probably buried under all the other replies, but I'll still leave this here just in case somebody may read it. \n\nAll answers given here are good but they are missing one point: that spam letter is only the first of the attack, and it is there to attract victims in the scam. Now, sending out a spam email is typically very inexpensive, but replying to the users that fall (or are curious) about the e-mail is: to maximise his/her chances of getting money out of the victim, the attacker has to reply to each user one by one (e.g. answering specific questions the user may make). The attacker wants therefore to receive replies from the lowest number of \"false positives\" possible as to not waste his/her time.\n\nThis is why the first e-mail is most times written incorrectly grammatically/syntactically: it functions as a first coarse-grained filter that lets only \"gullible enough\" victims in, i.e. users that do not get suspicious over an otherwise obviously weird email asking for money over the internet. These are also the users more likely to go through with the scam.\n\nI am not making this up. [Here's a scientific publication on the topic](ftp://_URL_0_). [FTP, OpenAccess]",
"Well, I have received some which still contain strings like $PROD_URL, so I wouldn't rule out incompetent spammers",
"I have a similar question. What is the purpose of computer viruses that don't give you ads and don't track your data? I had a virus once that did nothing but corrupt my boot files.. Why was that virus made? Just to ruin my day? ",
"I'm fairly certain they're systematically defeating bayesian spam filters.\n\nIt's actually rather brilliant imho."
]
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[],
[],
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"https://en.wikipedia.org/wiki/Bayesian_poisoning"
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[
"ftp.fixme.ch/free_for_all/Ebook/Nigerian_Scammers.pdf"
],
[],
[],
[]
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||
4dvijc | what does it mean when a game is well optimized vs badly optimized? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4dvijc/eli5_what_does_it_mean_when_a_game_is_well/ | {
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"A well optimized game has programming that allows a computer to process its graphics very easily without getting bogged down. It's done in a simple, efficient manner.\n\nA game that is NOT optimized has things wrong with the coding, such as being overly complex for what it does, that make the graphics card and/or processor work harder than it should.",
"This could mean many things. \n\nWhen it comes to CPU performance, it can mean that the game does stupid unnecessary stuff all the time. For example, pathfinding (finding the shortest walking path between two points) is fairly expensive, and if you have too much of that going on, performance may tank. It might also be that a programmer chose a simple, but slow algorithm for something, thinking that it would not be used enough to really matter, but ends up eating power. \n\nAnother very common problem is memory use. The memory is there for storing things you need to have quick access to - but if you start putting things into the RAM which you don't need often, or even don't need at all, you might end up using so much of it that you run out. The worst case is a so called \"memory leak\", where the program keeps storing more and more data in the RAM, until it eventually overflows and either crashes or reduces performance to a crawl.\n\nWhen it comes to graphics, it is mostly about unnecessary details. Having high resolution textures, objects with high polygon count and fancy special effects are good ways to make a game look good, but they can't guarantee it. Well optimized graphics use high details where they matter, but shave off details in places where they don't - for example, if something can only ever be seen from a distance, you don't need the same textures as you do for things right in front of your nose.",
"When people in /r/games are discussing it, they mean the game runs without framedrops, stuttering, or has low system requirements, despite having good graphics.\n\nSo a well optimized game has great graphics, but has low system requirements.\n\nA poorly optimized game, like the first binding of Isaac can get a good pc to start stuttering despite the graphics being from the year 2000.\n\npoor optimization is either caused by lack of budget/time \n(most console to pc ports), lack of knowledge of the developer or by the limits of the framework (Binding of Isaac)"
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