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3b4b6j | decrypting files. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3b4b6j/eli5_decrypting_files/ | {
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"Did you ever get one of those decoder rings in a cereal box when you were a kid? It works like that. \n\nWhen the file is encrypted, the computer uses it decoder ring to translate the file into an encrypted file. It gives you the file and you use your decoder ring, set to the same setting, to translate the encrypted file into the original.",
"In the simplest sense, encrypting a file is just like encrypting anything else. You use some sort of algorithm to take everything and change it to something else. A really simple example is \"ROT13\", where you just rotate each letter by 13 places in the alphabet. \n\nA - > O \nB - > P \nC - > Q \n... \nZ - > N \n\nThat's trivial to break, though. A little more complicated would be a random remapping, where you arbitrarily choose changes. EG, \n\nA - > Q \nB - > C \nC - > X \nD - > A \n... \nZ - > B \n\nThis is also dead simple. My local newspaper has one of these puzzles a day, where you can try to de-crypt the message with a pen and paper. You can usually figure it out based on letter pattern and frequency - E is the most common letter. If you see a word that's a single letter, it's gotta be either A or I. Work forward from there. Computers can figure these out in seconds.\n\nWe can make things a bit more complicated - use a bigger, more complicated algorithm which can't be reverse engineered. I'm not going to go into details on those, but you can look up DES / 3DES, AES, or BlowFish to get the actual details about the math. \n\nGoing back to your highschool math here, a \"function\" is a mathematical operation that produces a unique value for each input. As an example, y = 5x. 1 goes in, 5 comes out. 2 goes in, 10 comes out. A goes in, O comes out. \n\nModern crypto methods usually use a \"key\". The key and the data are fed into the algorithm and something scrambled comes out. Using the key and the algorithm the other way around, you can decrypt it. \n\nHere's a simple, insecure example:\n\n > Let's assign each letter a number. A is 1, B is 2, ... Z is 26. \n\n > Our encryption key is 427. \n\n > Our cryptographic function is OUTPUT = KEY * LETTER\n\nLet's say we wanted to send the message \"HELP!\"\n\n > We would look at the number of each letter there, and get \"(H)8 (E)5 (L)11 (P)15\"\n\nThen we run that through our crypto function: \n\n > 8*427 = 3416 \n\n\n > 5*427 = 2135 \n\n\n > 11*427 = 4697 \n\n\n > 15*427 = 6405\n\nSo now our output message is \"3416 2135 4697 6405!\"\n\nTo decrypt it, you just take the code for each letter, and divide by the key. \n\n > 3416 / 427 = 8. 8 = H. \n\nContinue till the whole message is decrypted. \n\nThere's a big problem with this approach in modern computing, though. \n\nLet's say I want to send you a message. I write you a message, scramble it all up, and send it to you. How do I get you the key? If I send it in plaintext, anyone listening (we'll call her Eve) can take the key and decrypt the message as well. The only way to really make it safe would be to meet you in person and give you the key. That's impractical for all kinds of reasons.\n\nThe entire internet, really, depends on something called \"Public Key Encryption\". Rather than use 1 key to lock a message, we can use two keys. One we share with the world, and one we keep to ourselves. There's a mathematical relationship between these two keys, but you pick them in such a way that you can't get one from the other. Anyone who wants to send me a message can take my \"Public key\" and use it to encrypt the message. The message can only be decrypted, though, with my private key. \n\nThink of it like this - I have a locked mailbox with a slot in it. Anyone who wants to send me a message can drop a letter into the box. Only I can get in and see the messages, since I have the key to open it. \n\nThis is a bit more than a 5 year old will understand, but if you've finished Algebra 1, here's the quick [explanation of RSA](_URL_0_)"
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4vvxdu | how do colourblindness correction sunglasses work? | I saw a video on Facebook today of sunglasses that allow colourblind people to see the full colour spectrum. I'm assuming that this is obviously doesn't work with black-white colourblindness, but how would it effect the most popular colourblindness disorders? I thought that this had to do with the inability to see certain colours, like red and green looking the same for example. I don't understand how looking through a specific substance could fix this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4vvxdu/eli5_how_do_colourblindness_correction_sunglasses/ | {
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"If you take the most common case, which is red to green colour blindness, The persons red and green photopigments have more overlap than normal, making them unable to see certain colors. Colour blind glasses work in a way to alleviate this by creating a specialized lens that filters out specific colors. \n\nYou can use these filters to target specific photopigments so you can affect what wavelengths (or colours) the person can see depending on what colours they are struggling with. Just because a person is colour blind doesn't mean that the colour they can't see is completely invisible to them, they just need some fine tuning which means blocking out the overlapping wavelegnths to enhance the less common ones. ",
"Glasses cannot correct colorblindness because that is a fundamental defect in the light receptors in the eye. What they do is filter out certain colors in order to increase contrast between others. But make no mistake, someone with colorblindness is not seeing any new colors with the glasses on.",
"Do you have link for the sunglasses? My father is color blind and would love to get him a pair. ",
"Another question, how would the world appear to someone wearing the glasses who is not colorblind?"
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3usugv | how do small businesses contribute more to the economy than large chains? | With small business saturday ive been seeing a lot about how supporting small businesses could end up putting more money into the economy. I wanted to know if stuff like [this](_URL_0_) was real, and if so how. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3usugv/eli5_how_do_small_businesses_contribute_more_to/ | {
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"They are \"less efficient,\" meaning more money stays in the local community and less goes to stockholders a thousand miles away. \n\nPut another way, large chains are very efficient at whisking money out of your town and distributing it to stockholders. "
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af6g19 | does cbd oil give you the munchies? if so, why? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/af6g19/eli5_does_cbd_oil_give_you_the_munchies_if_so_why/ | {
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"There are 113 known cannabinoids. Many have some effect or another on appetite, but those effects vary greatly.\n\nTHC, the most well-known cannabinoid (mostly for creating the 'high'), seems to have the greatest impact on appetite according to current research. THC is often found in small amounts in CBD oil (up to .3% is legal federally).\n\nTHC affects appetite in 3 ways. First, it boosts a hormone called 'ghrelin', which makes you feel hungry. Normally, the body only releases ghrelin when your stomach is empty.\n\nSecond, THC can interact with CB1 receptors in areas of the brain that modulate appetite (I think these interactions can actually boost or suppress appetite, depending on circumstance).\n\nThird, THC can boost dopamine and our senses of smell and taste, all of which help us get more pleasure from eating.\n\nTLDR ; CBD itself doesn't cause the munchies. However, it does quell nausea and pain. For people who struggle to eat enough because of pain or nausea, CBD could help.\n\nIf you're concerned about over-eating as a result of taking CBD oil, you shouldn't have any issues. Just consider using one of the totally THC free products, rather than one with .3%, to be safe."
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2fcuha | why does string theory matter? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fcuha/eli5_why_does_string_theory_matter/ | {
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"It is a theoretical framework that potentially allows for a 'Theory of everything' by incorporating gravity, and as such potentially approaches a more fundamental description of existence. \n\nAnd of course, the more correct our description of existence is, in all probability the more capable we are of dealing with and manipulating it to serve our needs. ",
"Physics, right now, is divided into two sections: general relativity and the standard model.\n\nTo simplify it drastically, general relativity basically discusses the physics of really big things and the standard model describes really small things. \n\nThe problem is, general relativity takes gravity into consideration and the standard model, because of the kind of maths involved, cannot. What this means is that it's hard to mathematically join the two models, which is a problem because most physicists think we can't have two different models to describe one thing (the universe).\n\nIf string theory is proven to be correct (and in my opinion that's a very big 'if'), it basically unites the two previous models by providing an alternate way of describing them. It uses lovely things like the existence of 11 dimensions and miniscule strings that vibrate and interact with each other to create matter and energy, and therefore can describe everything.\n\nSo why does string theory matter? It matters because it's a way of understanding the universe without having to resort to two different ways of analyzing it, and to many people, it's our best chance of doing so.",
"It doesn't. It can't predict anything about our universe. It's just a toy some people like to play with. \n\nEdit: I'm sorry if anyone got upset about it but this is the truth. String theory can't make predictions. A theory without predictions is not a theory. It's just a pretty story. ",
"Physics is essentially divided into two sections:\n\n1. Classical Mechanics : It deals with the objects of our world that we can visualize. To give you example it tells why a stone would roll down on a hill or why do the roads get slippery when it rain or how much you use when you punch some one in the face. I hope you get the idea.\n\n2. Quantum Mechanics: Here is something that deals with stuff we can't really see. How electrons and protons interact, how do atoms interact with each other and stuff like that. \n\nQM provides a mathematical model for microscopic world just as CM provides a mathematical model for macroscopic world. While classical mechanics is rather smooth, things turn chaotic when we enter into quantum mechanics. The position of particles are not certain, things don't move in predefined orbits and we explain stuff in probability. Also light can behave both as a particle and a wave.\n\nEinstein came up with this diabolical theory that combines the working of space time and gravity called General Relativity. It tell us how the universe works on a large level(how galaxies work, how planets revolve etc.) and what would happen if we are able to travel at the speed of light. Fascinating as it is the theory uses gravity which is not in the game of quantum mechanics as we saw that things are rather weird there and refusing to follow rules of macro world.\n\nNow the problem occurs. We have two different theories to explain our own universe which is not possible since it is one thing. Gravity couldn't be incorporated to quantum mechanics and that became a huge headache for scientist.\n\nLet's take and example. Consider a black hole which contains immense mass, so much mass in fact that even light can't escape from it's pull and this fucker travels at 3*10^8 m/s. Now a black hole is really small since all the mass is concentrated to a small point called singularity. How do we explain a black hole? through classical mechanics or quantum mechanics?The answer is neither. Both the model break down and that simple couldn't be the case. Scientist needed a theory that could unite General Relativity with Gravity.\n\nEnters String Theory. String theory suggests that we use objects called string for explanation of the behaviour of sub-atomic particles(electron, protons, quarks, muons etc.). Each string has a vibration and a certain kind of vibration(note) may lead to the creation of a sub atomic particle. For explanation you can imagine guitar strings but these strings are really really tiny. So let's say if the note C Minor produces an electron, D Minor produces a quark. According to this theory you, me and everyone and everything in this universe is made of these strings and the mathematical model for String theory combines Quantum Mechanics with General Relativity effectively.\n\nIf you break down anything in the universe to it's smallest it will come down to a string. So, what's the problem? The theory uses 10 minuscule dimensions and one that of time to describe the physics of the world. Imagine something so small and visualizing it in 10 dimensions!! As of now we don't have the technology to test it out. In fact even since it was formulated String Theory has never provided even one test scenario.\n\nSo why should you care? Because the maths mostly fits. And Mathematics never lies. Higgs-Boson just existed on theory up until couple of years ago but physicist agreed about its existence just because it fit the model. Hopefully we will in future be able to test out String Theory. It will also give us answers regarding to some the fundamental questions like where did we come from?\n\n\n\n\n"
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4c3ngk | computer browser adblockers are amazing yet every single phone adblocker can't do anything, whys that | I had a rooted phone with adaway and it still wasn't enough to stop ads from my phone. Clicking on something would constantly open another tab to another site telling me I had a virus and making my phone vibrate. Especially from file downloading sites.
Yet on my pc both chrome and Firefox cannot be cracked with ublock. Haven't seen ads on my pc in a long time. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4c3ngk/eli5_computer_browser_adblockers_are_amazing_yet/ | {
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"AdAway blocks advertisements by redirecting known sources of ads to localhost - essentially a /dev/null solution. The reason this is the preferred method on Android is because many devices are limited in what resources they have available - especially lower end or older phones. Additionally, these less powerful phones are the ones more likely to be AdAway users, because adverts also consume resources.\n\nHowever, if an advert comes from a source that is *not* already known, it will not be redirected to localhost. For this reason, it is important that you regularly update AdAway, as it does not automatically do so.\n\nAnother point to consider is that AdAway *doesn't always work*. Rooting methods change from phone to phone and ROM to ROM. In fact, it may be entirely possible that the hosts file is not actually modified at all.",
"Android: Firefox + 2 addons: NoScript + uBlock Origin \n(There's 2x uBlock 1 with and 1 without the origin part. Origin is the one getting updates.)\n\nuBlockOrigin\n_URL_1_\n\nNoScript (mobile version)\n_URL_0_",
"I use dolphin browser with a dolphin adblock plug-in. It is able to block most ads and doesn't not compromise the performance of the phone."
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1tlpju | why do gifts and pics on reddit take longer to load sometimes more than others? | Like this morning, for example. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tlpju/why_do_gifts_and_pics_on_reddit_take_longer_to/ | {
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"Either your ISP gets heavy traffic during peak times, reddit is overloaded, or it's in your head."
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2rbwlx | eli: why can't you see the fog that is immediately around you? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2rbwlx/eli_why_cant_you_see_the_fog_that_is_immediately/ | {
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"The moisture particles immediately around you aren't numerous enough to block the light. As you get farther away, a sufficient amount of particles exist to block the light.",
"You see the fog immediately around you just as much as the fog further away - it's just that the more \"accumulated\" fog you would have to look through, the more dense it looks. Since fog is usually experienced outside (no shit, Sherlock), everything you look at is pretty far away - so even a density of fog that doesn't make a difference at an arm's length accumulates to a strong visual impairment at those long distances outside. \nIt's the same concept like dirty water (or most colored fluids really) - you can see something just fine when it is just below the surface, but the further down it is, the less visible it becomes. ",
"Fog is made of tiny water droplets in the air. Light bounces off each droplet in such a way that, if you look through the droplet, you won't be able to see through it. Instead it will look white, or whatever color light is nearby. \n\nIf there's only one very tiny water droplet in the air, you won't notice it, which is what you're seeing directly in front of you on a foggy day. But then, as you look further away, you're no longer looking at just one droplet; you're looking at hundreds, then thousands, then millions and tens of millions. Yes, each droplet is very small, but once the number of droplets that you're looking through reaches a certain amount, you can no longer see through them.",
"Take a bunch of ziplock bags and stack them together and try to look through the stack. It's the accumulation of the opacity that results in not seeing through a bunch of it, but still being able to see through one of them.",
"Think of it like looking into a forest. You can see around you cause there's just a few trees, but past a certain point they overlap too much for you to see anything."
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1gm9z6 | if china is not fully communist. what aspects of the country are? eli5 | People don't all get paid the same as the economy is not socialist. The only thing I actually know of China being different is that it's a single party state and they have restrictions on stuff like Internet.
So.. What makes China communist? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1gm9z6/if_china_is_not_fully_communist_what_aspects_of/ | {
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"EDIT: This ended up longer way than I expected, but it's still ELI5 material. I'm going to keep adding and revising info as it comes to me.\n\nThink of it this way: Communism means you get what you want, within reason.* A lot of people think that means that Suzie and Billy will always get 3 trucks, 5 dolls, and 2 race cars, even if Suzie doesn't want the cars and Billy doesn't want the dolls. Really, it means that Billy can get 6 trucks and 4 race cars, and Suzie can get 10 dolls, which is even better.\n\nAnyways, a long time ago, a man named Mao Zedong told a bunch of people that everybody deserves to live under Communism. They'd take the toys from the rich kids who had many and didn't share, and share them with everyone. Many people agreed with him, and so there was a big, long fight that ended up in a Socialist (like simple Communism) state in China.\n\nUnfortunately, it didn't all go as planned. Mao, instead of sharing like a good boy, decided to keep a lot for himself and his friends. Instead of everyone getting 10 toys, Mao and his friends got 15 each, and everyone else just got 5. That made a lot of people sad. Plus, he made very big plans: the Great Leap Forward and its \"5 year plans\" (5 years, just like how old you are!) to build more toys for everyone in China and the world. Everyone knew the plans would make life harder for everyone, but Mao promised that it would be better when they were done. But those plans didn't work, and resulted in a lot of broken toys and people working too hard and not getting enough candy and toys in return. This made people very sad, or even angry.\n\nMao and his friends got angry at the sad people. He said that the sad ones were being mean to him (it's silly, isn't it?), and so started being even more mean. In a program called the Cultural Revolution, he started limiting freedoms to everybody who wasn't his friend. For example, if you said you didn't like how the Communist Party gave out toys, you could be arrested. He also started taking even more of the toys, so he and his friends had very many and the rest of the people had very few. Also, instead of being able to choose what toys you wanted, you'd basically get exactly what the Party (not a happy party, it's a name for Mao and his friends) gave to you. This had happened before, but the Cultural Revolution made it even worse. The worst part of the Cultural Revolution was that if you didn't act almost exactly like how the Party wanted, you could be hurt very badly (or even killed, but don't worry about that until you're older). The Party started destroying a lot of culture, religions, and historical stuff because they were afraid of the people liking their old cultures better than they liked the new government.\n\nEventually, Mao died. This made the country pretty unstable, almost like mommy and daddy getting in an argument, but a lot worse. His group of friends (the Party) decided that they wouldn't do things exactly like Mao would have wanted. They allowed for more trade with other countries, even ones that don't share toys in a Communist way. Basically, the other countries had a lot more toys and wanted to open up toy factories in China. That gave the other countries a lot of money, and it gave the Party money too, but most people were just hurt even more. Because the people were so angry, the Party started limiting free speech even more, including restricting access to the Internet so people couldn't really communicate!\n\nSo with all of the other countries making life hard for the people, the Party being mean to everyone, and limiting people's rights to free speech (called censorship), China isn't at all Communist any more. However, the Party still says they're Communist because that's what they've always said, and they really like praising their old friend Mao.\n\n*It's a lot more complicated than that, but I'm ELI5ing it.\n\ntl;dr: Mao said he'd share toys, but he only shared with his friends. He also was mean and said you weren't allowed to say you didn't like what he and his friends did. In real Communism they wouldn't have done that.",
"Another thing I would like to add is that when Mao founded the PRC (People's Republic of China) it was when western states were industrializing. Witnessing the prosperity derived from industrialization Mao wanted China to move forward too. Imitating the USSR's 5 year plan (the communist big brother at the time), China initiated the Great Leap Forward that was their version of industrialization. However, they had absolutely NO IDEA what they were doing. A lot of people starved to death from unrealistic state procurement (demands)! They even started melting random scraps of metal in the hopes of making iron in their own backyard, which obviously was not happening. \n\n\nTo address your question, I would say China's one party state system makes it inherently a communist country. After Mao died, he was succeeded by Deng Xiao Peng. He told the people of China that if they wanted prosperity then they must submit to the Four Cardinals. They were more along the lines of \" First, you must always remember the words of PaPa Mao, and Grandfather Marx. Second, always support this dictatorship. Third, continue to support the road to socialism and most importantly support the state party CCP to run this country.\"\n\n* Hopefully a 5 year old sort of get's the idea, I really dumbed it down!\n\n\n",
"Why are the USA considered a democratic country?\n\n* Although a majority of the population voted for Gore in 2000, Bush became president\n\n* Free speech: See Bradley Manning and Edward Snowden. If everything you say on telephone/internet is recorded and can be used against you, it is not a free country, I would say.\n\n* With politicians being only paid by the state to a little extent in comparison to what they get by private companies wouldn't you rather think it is a plutocracy?\n\nI think there is a gap between what a government calls its form of government and what form of government it resembles most. I don't think \"communism\" ever existed, countries which claim(ed) to be communist are/were mostly totalitarian dictatorships."
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52rnh2 | if bodies miscarry babies that have abnormalities why are there still children born with defects? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/52rnh2/eli5_if_bodies_miscarry_babies_that_have/ | {
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"Handicapped babies don't automatically miscary, an otherwise healthy baby can be miscaried due to many other reasons as well.",
"The obvious answer to your question is that bodies do *not* miscarry fetuses with abnormalities. \n\nThey *can*, and it does *sometimes* happen. But it's clearly not guaranteed to happen. \n\nMost early pregnancy miscarriages happen because the fetus was not viable, not because of an abnormality. \n\nMiscarriages also happen for a great variety of reasons. We don't really know them all. ",
"The problem here is in the word \"if\". It's not necessarily that the body deliberately aborts genetically abnormal embryos, it's that some abnormalities are severe enough to prevent the child being carried to term. Some are not, and those are the ones you're talking about.",
"If a body miscarried any abnormalities as measured against the mothers body, there would be absolutely no evolution. Ever. The entire concept of evolution is that sometimes a child is born with a new trait that makes it able to thrive better than its parents, and that trait is passed on to its offspring.",
"Bodies don't always miscarry babies with abnormalities, and healthy babies can sometimes be miscarried as well. ",
"It is not very common for miscarriages to be due to abnormalities in the fetus, though it does happen. Most miscarriages are due to abnormalities in the mother's biological functions during pregnancy rendering the fetus non-viable. ",
"I'm not sure there is a real way to explain this so simply, but in general, the more severe deformities/abnormalities cause inter-uterine demise of the fetus (ie. the baby dies really early) and that causes miscarriage before 20 weeks. The abnormalities that persist are usually the ones that aren't as severe or, if they are severe, aren't a problem until the baby has to survive outside of the very protected environment of the womb. \n\nIe. babies with lung problems in utero won't have issues because they don't have to breathe, but once they're born, the lungs don't work. \n\nAlso there are a LOT of ways in which abnormalities might show up - from too many/too few chromosomes, to specific genetic issues to things that happen to the fetus/mom when the fetus is developing (certain diseases like rubella can cause heart defects in the fetus). Abnormality is a loose term, and there are a lot of abnormalities that allow the fetus to make it to term but not do that great outside the womb. \n\nAlso, there is no \"perfect\" human born without any imperfects at all. We all have some small abnormalities and imperfections, the ones with more amplification are the ones with highest rate of issues that are more likely to lead to miscarriage/stillbirth. \n\nIf you have specific questions feel free to ask. Just finishing up my OBGYN rotation in med school. "
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86csuy | do people who wear glasses have whiter eyes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/86csuy/eli5_do_people_who_wear_glasses_have_whiter_eyes/ | {
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"Not that I’ve ever heard. \n\nI’ve worn glasses for the past 15 years or so and my eyes definitely have their no-so-white days. \n\nYou may be noticing a difference because 1) lenses tend to magnify the eyes a bit, making them appear slightly larger in general. In addition, 2) they could be magnifying the amount of light coming through them and shining on the eyes. \n\nThis one’s a bit less common but there are some people who wear contacts despite them causing a slight irritation to their eyes, which would make them appear more watery or bloodshot. When I had to switch brands of contacts, the new ones scratched my corneas and I was bloodshot for over a month until everything healed (this why I mostly wear glasses now)"
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30a0h1 | why do the darker green parts of lettuce seem to wilt/age faster than the lighter green portions | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/30a0h1/eli5_why_do_the_darker_green_parts_of_lettuce/ | {
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"text": [
"The lighter sections are the regions closer to the stalk that contain more water and are of a more rigid, fibrous composition. The leaves wilt when they become dehydrated. "
]
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[]
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85tkel | why have photocopiers not improved like digital photography? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/85tkel/eli5_why_have_photocopiers_not_improved_like/ | {
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"perhaps the copier was dirty, or maybe the source doc was blemished?\n\na scanner can do upwards of 9600DPI for high end consumer units. that would produce a scan that would exceed the source detail of pretty much anything you could imagine...\n\nthough it takes a lot of time to do, so most scanners are probably setup to scan at something much much lower."
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su4tc | question regarding planets and gravity. specifically earth...does its mass increase over time from meteors and if so won't that eventually pull the moon into earth? | So I realize that most meteors are basically very tiny (relative to the Earth) and individually are unlikely to significantly affect the Earth's mass. But since they've been hitting the earth for a very long time now wouldn't that slowly increase the mass of the earth? If so, wouldn't that then increase its gravity? And wouldn't that mean that eventually it would be enough of a change to pull the moon towards us? Probably not any time soon, but I mean over a sufficiently large period of time? And if so, how will this gradual increase in mass and therefore gravity affect our orbit around the sun and possibly the orbits of everything else in the solar system?
((((i submitted this to /r/askscience but got completely ignored as usual, really curious to know about this though)))) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/su4tc/question_regarding_planets_and_gravity/ | {
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"The masses required to have any measurable effect would be really high! So I wouldn't expect meteorites to have any effect on the gravitational system of the earth and moon. Also remember that the moon is struck with meteorites as well, meaning that its mass grows gradually over time just as the Earth's does.\n\nBasically what it boils down to is that these small changes in mass even over a very long period of time are just not enough to have a big effect on the gravitation system.",
"The moon's stealing the earth's angular momentum and receding will vastly outweigh any effect this might have.",
"The mass added via meteorite impacts is negligible. ",
"The Earth also loses mass as the Atmosphere is lost to space. "
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1oukh4 | why are tv series produced and aired in seasons, instead of a more continuous way? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1oukh4/eli5_why_are_tv_series_produced_and_aired_in/ | {
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"The people involved in the production like to have some time off. Soaps do more or less what you describe, and it's generally considered pretty stressful. "
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2o8207 | what would happen if every country in the world suddenly started using the same currency? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o8207/eli5what_would_happen_if_every_country_in_the/ | {
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"There is no way to answer this question without knowing what controls the currency and the conditions of that control. Without that information, the question is meaningless.",
"It depends. If it goes off the USD then this would give Americans massive amounts of power as they would dictate the monetary policy and can print off new money for itself for the most part at the expense of everyone else. Whereas current when they print off new money they harm themselves for the most part. So the government tends to print as little as possible new currency; generally speaking.\n\nMeanwhile currently say Canada can do the same. They print off new money to fund itself as needed. \n\nIf that changed. Canada now can't print money to cover off its mistakes and needs. They end up forcing themselves to take less risks and acting more fiscally conservative. Meanwhile the USD could print itself and harm the Canadians. \n\nSo what would happen would be far more commonly there would be countries having economic failures that they can't just print off money and the USD value would drop far less than it has been historically.\n\nNow if we posit a currency which doesn't have a central country of control; much like bitcoin or perhaps the Star Trek federation credit. The problem is that inflexiblity of the currency is a lost tool that for the most part that isn't beneficial to society. ",
"Individual country's would lose the flexibility to recover when experiencing economic downturns. As was the case in the European Union recently when countries like Greece were struggling, but countries such as Germany were doing well, the monetary policymakers in the EU struggled to balance the conflicting priorities. Controlling the currency allows an economy to affect the rate of spending in the economy. For example, when the US Federal Bank adjusts the prime interest rate, it's like making money more \"cheap\" or more \"expensive\" to buy. If interest rates are low, you can buy more money because it's cheaper (you can afford a bigger loan because the monthly payments will be lower). If your country does not have control over it's own currency, then it cannot adjust the rate of spending and will thus have a much harder time responding to economic booms and busts. If every country in the world used the same currency, then none would control their own ability to balance out their economies in an attempt to avoid too much or too little growth.\n\nTL;DR Longer recessions for individual countries and little ability to affect recovery.",
"This happened with Greece's debt crisis and the Euro. Inflating your currency by printing more money is not *always* that bad of a thing. It redistributes the volume of wealth away from currency-holders and debt-holders back to the government. It moderates the effects of crushing debts, as the value of currency units paid back drops, but this is better than a total crash with no payback. It also increases your exports as your products become cheaper and thus in higher *foreign* demand, which partially restores the demand for your currency unit. Done wrongly, it can easily lead to hyperinflation, but it doesn't have to.\n\nGreece ran into this because they had too much debt but have no power to print more euro. They can't deflate their currency because it's shared, which would have reduces the cost of their debt and increased their export. Basically they couldn't \"fix\" it and the multiple austerity packages since then arguably caused more problems than they solved. Spiralling hyperinflation is bad, but it probably wouldn't have come to that. Austerity measures can kill your GDP and bring down an economy. \n\nGreece's debt has done a lot, by complicated extension, that devalued the shared euro. Even WITH the austerity packages inside Greece. From what I can tell, it was largely due to loss of confidence in the euro if Greece simply defaulted and said they would not/could not pay back lenders. \n\nThis is an alarming example of [Moral Hazard](_URL_0_), where a party takes more risks and likely to cause more problems *because* another party bears the burden of those risks, removing consequences from actions. In this case, the entire Eurozone shares the burden if a nation defaulted. The logical assertion is that Greece was reckless in its borrowing for many years because the rest of the Eurozone would bear most of the fallout if they had to default or leave the Eurozone.\n\nTo ELI5? Say Inzan appears to be rich nation. They have oil and other resources. They take out a tremendous- if not crushing- line of credit over the years, $10T in Whole Earth Credits (WEC). Then they say \"we will not pay creditors back. Anyone. We think the terms were unfair. It's the former president's fault, he was corrupt and sold us out to foreigners and we got nothing!\" Others say \"well... you just can't DO that.\" Inzan says \"You can't legally invade us. Hey, does anyone want to buy our oil? Our currency is now the Inzan Erg, and all transactions for our oil are to be done in Erg.\"\n\n1000 oil brokers from across the globe say \"well, of course, oil is 100 WEC a barrel! Get us that price and we shall buy\" 1000 currency trading speculators now say \"don't worry we will trade WEC for Erg and Erg for WEC and you can buy Inzan oil at the same price as if it were WEC.\" \n\nBut some lenders say \"fuck the WEC, the market just got burned for $10T. We have more confidence in the Erg, honestly, because the way they're managing it, I can always buy Inzan oil with it. Today I think the Erg is worth more than yesterday, and the WEC is worth less than it was worth yesterday.\"\n\nOther nations do the same thing, profiting themselves while devaluing the WEC. WEC becomes worthless and ceases to exist. Returning us to the natural state of controlled chaos that is the world banking system of different currencies. And for that same reason, why a whole-world currency has never risen."
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1cahyf | what exactly did tiger woods do at the masters that's causing such a fuss? | Some are saying he cheated and should be DQed. And I don't know any of the rules in golf, though I think low scorer wins. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1cahyf/eli5_what_exactly_did_tiger_woods_do_at_the/ | {
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"He took an illegal drop. \n\nIn golf, if your ball encounters some sort of hazard and cannot be played, you have to drop your ball nearby. However, there are very strict rules about where you can drop it, how far away you can drop it, which direction from the hole you can drop it in, what technique you use to drop it, and when you can actually drop it in the first place. \n\nTiger, unfortunately, did not follow one of these rules. He dropped the ball outside of the designated drop zone. Thus, he gets a penalty. We can't say if he cheated because we don't know whether or not he knew he was breaking the rules while he did it, but he still broke the rules so he gets a penalty. \n\nThe rules of golf are very strange, many make no sense whatsoever, and a good chunk are leftovers of the days when you had to wear suits to play - remember that when the rules stop making sense. A good chunk are there quite literally because \"it's traditional,\" even if that means going against common sense. "
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1uhyvl | why do black and white photos tend to be more creepy than colored ones? | Whenever I look at a black and white photo compared to a colored one, I get more of a cringe looking at the black and white one. There is something about them that is creepy.
Example- _URL_0_
This wouldn't be as creepy if it was in color. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1uhyvl/eli5_why_do_black_and_white_photos_tend_to_be/ | {
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"To me, I think it is because we SEE in color. If we look at a picture that has no color, only black and white, it causes a sense of mystery and for most people that is interpreted as creepiness/scariness. ",
"That particular picture would probably be creepy in colour as well.\n\nAnyway, the reason it looks more creepy is because it looks familiar, you can identify what the objects are, but because you see the world in colour your mind asks \"why is there no colour here, there should be colour here, what's happened to the colour!\" and this causes the wiered off putting feeling."
]
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13whtl | i don't know what it's called so i'll just put a picture of it in the text. how does this work? | I don't understand [this](_URL_0_) at all. What makes your brain change the colors to what they would normally be? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/13whtl/i_dont_know_what_its_called_so_ill_just_put_a/ | {
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"That's called a negative, by the way. Basically what that means is that all the colors have been 100% reversed - white is black, black is white. While you stare at it, your brain is doing something called \"neural adaptation.\" Basically your brain, instead of re-drawing the picture constantly, says \"Yep, nothing's changed. Still nothing. Still nothing.\" If something does change, it reports that, rather than reporting the entire new image. As part of this change-hunting process, your brain kinda \"turns down the volume\" of the colors you're seeing, because there's been no change and it's hunting for changes it can report - new colors. \n\nSo all your other color receptors are still reporting at full strength. Thus, when you close your eyes or look at something else (like a white screen), all the other color receptors are still firing at full strength, and the ones that *were* being suppressed are now both suppressed an inactive.\n\nWhat you're left with is a negative of the image you were looking at - in this case, since you're looking at a negative, you're left with the positive, or the colors as you'd perceive them normally.",
"The effect is commonly called an \"After Image,\" which will help you find more info on it if you want more than you get here. The truth is, like many brain/vision phenomena, we're pretty good at describing what happens and manipulating it, but the exact \"why\" the brain does what it does is sort of still under debate.",
"It's not your brain doing it, it's your eyes. \n\nSay you're looking at a red square for a while. you're not moving your eyes, so the square is projected on the same part of the retina for the whole time (the retina is the back of your eye that detects colors). \n\nWhat happens is that after 30 seconds the sensors of your retina get \"tired\" with all that red, so they send less \"red\" information to your brain (though it still looks mainly red).\n\nNow when you look away at a white screen or wall, the sensors are still tired by all that red. They should be seeing white, which is all primary colors (red green and blue), but since they send less red, it looks as if there was more green and blue, which make a cyan color instead of white. You see a cyan square because cyan is the opposite color to red (the negative color).\n\nIf instead of looking at just a red square you look at a negative picture of something as in your link, the effect will produce the negative of that negative, that is the picture with the right colors.\n"
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fpifrd | the technology/algorithms behind aim-botting in an fps. | So I get that someone can cause their character to aim at another character but the question is more along the lines of how it works?
Is it an X,Y axis on the user’s screen and the aim bot detects the enemy on that plain and just moves the user’s cursor to that X,Y coordinate? Or is it more along the lines of detecting where on the map the player is through the games code?
I have no background in coding I was just always genuinely curious what math / calculations allows people to do this.
And before you all ask, I have no interest in using this information to my advantage, I think cheating in any game is pointless and a nuisance. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fpifrd/eli5_the_technologyalgorithms_behind_aimbotting/ | {
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" It's more manipulation of a game engine than math. Each entity has an id, aimbots simply track the id and location and calculates where to put the sight based off how the engine handles physics. This is why each aimbot is programmed per game. call of duty for example is hit-scan so if sight is on the pixel of the enemy head on trigger pull it's an instant hit . Whereas battlefield has travel time for it's bullets requiring the bot to account for travel time, drop and velocity. While it all looks 3-d to us, Inside the game code it is still just from pixel a to pixel b based on the games physics engine.\n\nSorry this isn't exactly the answer your looking for but since this is Reddit someone who actually knows in detail will be along soon to correct me and you'll get a better answer lol."
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5rgx3k | how light pollution works, and would the stars appear straight away if we turned the lights off on the entire globe? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5rgx3k/eli5_how_light_pollution_works_and_would_the/ | {
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"The air has lots of microscopic particles floating about in it. Light from sources on the ground may reflect off these particles back towards the ground, thus more light from the ground will increase the ambient light level of the sky. This happens at the speed of light, so light pollution would go away nearly instantly if all the lights in a region turned off.",
"Of course there's light entering your eyes directly, scattering in your eyeballs and preventing your eyes from adapting to the dark sky properly. More important on a large scale is that a lot of the light emitted skyward is also scattered back down. If it's cloudy you can easily see the clouds are lit up, and how the light reflected back down makes the ground brighter in quite a large range.\n\nEven without clouds, there is scattering within the atmosphere, more at the blue end of the spectrum (for the same reason the sky is bright or dark blue when the sun or moon is out). It's been a mixed blessing that lights were mostly yellow until recently. Some is still visibly scattered downward, but less than if it were blue.\n\nIf you're in a darker region, you can see domes of light above cities. It's very obviously deteriorating visibility in that direction. That's still just the tip of the iceberg because it still has an effect in other directions, just not such a blatantly strong effect.\n\nGetting rid of all the lights has an immediate effect, not unlike flicking the light switch in your room. A massive power outage would be amazing. Measures that people would be more likely to accept are concentrating light where it's needed most and still using as little as possible, avoiding the blue end of the spectrum, and using armatures that don't send any direct light to the sky.",
"You know how when you are watching TV with a bright light on in the room some of the light reflects off the TV screen and makes the image harder to see? It's kind of like that, imagine the atmosphere is the TV screen, the stars are the image being projected through the screen, and the light from pretty much every light source on the planet is reflecting off the atmosphere making the stars harder to see.",
"The stars are never \"off\" unless they die, so yes, you'd see them immediately. \n\nThe problem is our star and the lights on the ground appear bright to us because of distance, that our eyes cannot adjust to see the starligt. Even if your eyes could dilate in bright light I think all you'd find is pain and overstimulation instead of clarity."
]
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90sjln | why do things like colored balloons and stained glass have colored shadows? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/90sjln/eli5_why_do_things_like_colored_balloons_and/ | {
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"They act as filters. The reason they appear colored is because they're only letting through light of that wavelength(s).\n\nTranslucent objects still cast shadows. They're just not as dark as shadows from opaque objects.\n\nSo the only light that gets through < color > stained glass is < color > . If < color > light hits a surface that reflects < color > (like white paint), then you'll see < color > in the shadow."
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46wtk5 | how did the ligo detector avoid data errors from things like heat expansion and seismic waves? | The accuracy of the device was accurate to within 1/10,000 the diameter of a proton, something I thought was impossible for humans to accomplish. How did they keep those lasers in phase so well while the tunnels would experience natural changes due to heat expansion and waves already affecting Earth? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/46wtk5/eli5_how_did_the_ligo_detector_avoid_data_errors/ | {
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"They can't avoid those things. They took them into account. For example, at the time of the detection there was an earthquake in Africa. They did the calculations and based on the strength of the earthquake determined it couldn't have caused the data they saw.\n\nSo they are extremely careful about accounting for everything that can cause signals in the detector, and filtering those things out. They also had people deliberately faking data to make sure the detection team was really doing their best. So when the real detection happened they made sure it wasn't any other thing, and the fake data team confirmed that they didn't fake data at that time, meaning it was a real signal."
]
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f23jiu | how is the structural integrity of very old buildings, bridges, etc. tested to ensure suitable use by people, cars, etc? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f23jiu/eli5_how_is_the_structural_integrity_of_very_old/ | {
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"Civil engineer here. For old buildings, if they have the architectural plans then they can usually derive all the mathematical info they need and account for decayed members. If they don’t, they’ll try to generate one and usually schedule renovation. That’s mainly for old buildings like houses. Bridges can be tested for a variety of factors - they use a lot of deflection analysis, so like seeing how much a bridge will sag under a given load, or how much it’s cables (assuming suspension bridge) extend under that load. A lot of visual analysis occurs as well - cracks, rusty rebar, split timbers can all indicate the current state of the structure and can be accounted for in projections of how long it will last based on modeling. Other methods can also be used to look for wear *inside* a structure, like using electrical pulses or vibration feedback on concrete. Also, because building codes are so meticulous and regulated, a good inspector can actually refer to old building manuals and practically determine from those what kind of design life a structure was built for. It’s a fine-tuned skill and one of the aspects of civil engineering that is highly valued because of the experience it requires.\n\nMy timber design professor was such a knowledgeable guy that he was brought in to inspect why a frame holding a very expensive painting fell, and it didn’t even take him long to figure it out. \n\nHonestly it’s pretty cool. Good question!",
"The most basic is looking for deterioration, looking for where corrosion has occurred, bricks fallen mortar cracked, and can get a general idea of the condition. Tension cables can be tested for how much tension they're under, and can have electrical current run through to check for corrosion.",
"On the back of this, are they periodically checked? A bridge in Nottingham has been declared unsafe as they found rust in the support s or something, I’d like to know how and why they found out.",
"I'm a Civil Engineer too from Brazil, let me just mention something.\n\nIt's very usual here to have old buildings which you haven't got the structural plans to, and you can't guarantee the original builder followed the codes of the time (they don't even follow it now.)\n\nSo one technique that's particularly interesting to test the strength of the concrete is that you can cut a cilinder out of a few columns (there are places in the column that you can do this safely) and test that cilinder's strength on a concrete press. This tells you how strong the concrete is, and you can close the hole with stronger concrete later.\n\nThis is called destructive testing, and there are many non-destructive methods available, but this is a fairly straightforward as many labs would have a concrete press.\n\nOf course this doesn't cover the steel reinforcement, but as was already said that can be evaluated by other techniques.",
"\"Okay Joe bring one more elephant up here\" crash. \"Yup that bridge was only 4 elephants strong\"."
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2gaa77 | why are some replacement parts for electronics (i.e. laptops) nearly as expensive as the whole unit? | My customer bought a new 300 euro laptop and immediately broke the screen, the official supplier offers my shop an original replacement screen for 280 euros.
That's the price for the screen only, without tax, installation and my shop's markup, so it's price for the end user would be higher than buying an identical new laptop.
How and why?
In the end, I ordered a generic chinese LED panel for 50 euros with shipping and installed it to the customer for 10, for a total of 60 euros for the end user, an amount that seemed somewhat normal in our eyes. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gaa77/eli5why_are_some_replacement_parts_for/ | {
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"text": [
"Bulk manufacturing pricing. They buy 10,000 screens from a suppler. That drives per unit costs down. You need to buy one, no incentive for them. "
]
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|
brg6wi | in the united states is every last digital dollar backed up by a paper noted currency? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/brg6wi/eli5_in_the_united_states_is_every_last_digital/ | {
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"No, very little U.S. currency is actually backed by paper notes. Something like 10%. [According to this](_URL_0_), there is about $10 trillion in wealth held in cash or cash equivalents, but money supply is about $980B"
]
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"https://www.independent.com/2011/09/25/How-Much-Money-Is-There-United-States/"
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||
2fx4ao | why are russian nuclear bombers allowed to fly so close to the united states (and vice versa)? in the event of an actual attack, wouldn't it be already to late to stop the bomber once it launches its cruise missiles or goes on its bombing run? | The bombers usually fly very close (but not technically violating U.S. airspace). Wouldn't the optimal time to stop them be when the bombers are still traveling the distance between Russia and the contiguous U.S.? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fx4ao/eli5_why_are_russian_nuclear_bombers_allowed_to/ | {
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"Russia still has planes flying around? I didn't think they did that anymore.\n\nThey are carefully watched and the airforce will have planes handy to scramble and stop them if need be. We cannot force them out of flying where they legally can fly, so we just take measures to make sure that A) It never comes to that and B) We have assets in place to stop it.",
"Yes, it would be too late by that time if, for some reason, a Russian bomber decided to let off a weapon against the United States in some manner. You would sacrifice whatever area or asset was targeted at that time.\n\nThe reason that the US does not intercept these aircraft is because they know that the Russians know that any such attack would result in immediate, massive, overwhelming response against their own nation. Swift and brutal retaliation. So the US military calculates that there is an extremely small possibility of the Russians attacking via these aircraft, because why would they? Why would they attack and destroy Boston, or Anchorage, for instance, if they knew that their entire country would be under siege by ICBMs within 15 minutes? The risk of a mistake, a crash, an error, an overzealous pilot shooting down a foreign aircraft by accident leading to an unwanted military conflict is much higher than the chance that the Russians will decide to launch a one-off attack with a few bombers."
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kzpmi | deduction and induction | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/kzpmi/eli5_deduction_and_induction/ | {
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"Deduction - drawing an inference from premises that, if your premises are true, must necessarily also be true. A successful deductive argument is labeled \"valid.\" If the premises of a valid deductive argument are true, then the argument is \"sound.\"\nExample: All the balls in this urn are red. I will draw a ball from this urn. Therefore the ball I draw will be red.\n\nInduction - drawing an inference from premises that, if your premises are true, is likely to also be true. Typically, induction operates via pattern recognition and assumptions that correlations between events that regularly occur together will continue to occur together. A successful inductive argument is labelled \"strong.\"\nExample: Every ball I have drawn out of this urn thus far has been red. Therefore it is likely that the next ball I draw will also be red.\n\nBonus - Abduction- Making an inference whose warrant is derived from the way that the inference would explain observed events. \nExample: Every ball I have drawn out of this urn thus far has been red. Therefore it is likely that all the balls in the urn are red. ",
"Deduction - drawing an inference from premises that, if your premises are true, must necessarily also be true. A successful deductive argument is labeled \"valid.\" If the premises of a valid deductive argument are true, then the argument is \"sound.\"\nExample: All the balls in this urn are red. I will draw a ball from this urn. Therefore the ball I draw will be red.\n\nInduction - drawing an inference from premises that, if your premises are true, is likely to also be true. Typically, induction operates via pattern recognition and assumptions that correlations between events that regularly occur together will continue to occur together. A successful inductive argument is labelled \"strong.\"\nExample: Every ball I have drawn out of this urn thus far has been red. Therefore it is likely that the next ball I draw will also be red.\n\nBonus - Abduction- Making an inference whose warrant is derived from the way that the inference would explain observed events. \nExample: Every ball I have drawn out of this urn thus far has been red. Therefore it is likely that all the balls in the urn are red. "
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p4wcf | the different schools of economics | Keynesian, Chicago, Austrian & Marxian.. I know a bit about each, but would love it broken down 5 year old style.
Advantages/Disadvantages of each? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/p4wcf/eli5_the_different_schools_of_economics/ | {
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"If I can ask a similar question: can anyone send me to a place to explain inflation to me? Like why its so important/necessary and so on? No idea where to look for that. I'm 21 and none of this economic stuff makes sense to me.",
"What's neo-classical? I vaguely remember talking about it in my Macro class in high school, but haven't seen it mentioned here?",
"I'll try my best, this isn't 5 year old style but I don't think it's too hard. I'll try to describe them all as nicely as I can. There are a lot of technical differences between schools but I don't think those are really important.\n\n**Chicago School:**\n\nOpinions on free market:\nThey believe the free market is mostly efficient and free market societies are happy and free. They place great value on the opinions, decisions and desires of the individual. Milton Friedman, a famous, economist of this school, fought against the military draft in the US, he thought the system was akin to slavery. \n\nOpinions on government:\nGenerally distrustful of it. They believe that regulations tend to make matters worse, not better, and that a lot of the regulations are simply attempts of powerful people milking the system. \n\nOpinion on recessions/business cycle:\nThis is the monetarist approach, the one by Friedman. A central bank creates money. When it creates too much there is inflation, when it creates too little there is disinflation. Recessions are caused when the money supply, ie the amount of money in the economy, suddenly decreases, therefore to fix a recession you have to increase the amount of money in the economy. In very simple terms, you have to print money, not too little, not too much.\n\nAdvantages:\nIncreased freedom of choice for costumers and business alike, this will make a better society for everyone. They put forward solutions to getting out of recessions.\n\nDisadvantages: They don't value equality all that much. They don't seem to have any plan for solving market failures, like for instance the health care market in the USA which is quite bad.\n\nWhy they think no one listens to them:\nPeople don't want 'equality' or 'liberty', they want to control the lives of other human beings and rob them of their ability to choose for themselves, and instead ensure they live the lives the government elites consider proper. If you want to help the poor live better lives why does the government give them food stamps instead of money? Because the government doesn't want the poor to decide for themselves.\n\n**Austrian:**\nRelatively similar to the Chicago school in general.\n\nOpinions on free market:\nThey believe the free market is mostly efficient and free market societies are happy and free. They place great value on the opinions, decisions and desires of the individual. Most libertarians in the USA like the Austrian theories. \n\nOpinions on government:\nGenerally distrustful of it. They believe that regulations tend to make matters worse, not better. They believe that government restricts freedom so much it makes societies extremely miserable for its citizens. They were extremely critical of government which makes a bit of sense as most economists of the Austrian school lived during fascism and communism. They are against government finance, ie central banks.\n\nOpinion on recessions/business cycle:\nRecessions/business cycles are created by banks in general, including the central bank. I'm going to explain it for the current recession as I was doing a bad job explaining it in general. The central bank lowers the interest rate, suddenly the interest rate on a mortgage is quite low. Everyone rushes in to buy a house. The market reacts by building many houses as everyone is buying them. A lot of people end up employed building houses. The housing market ends up being a speculative bubble, no one is willing to buy houses any more so the investments end up being unprofitable. Suddenly all constructions workers end up unemployed and we have a recession. Solution: no central banks. Some also believe in the gold standard, basically the fact that 100 dollars should be equal to 1 bar of gold (or any other arbitary amount of gold), there would be no recessions with this policy.\n\nAdvantages:\nIncreased freedom of choice for costumers and business alike, this will make a better society for everyone. Includes ways on improving the financial sector.\n\nDisadvantages: In my opinion, they went a bit over board in basically everything, their dislike of finance is nice and well but just a bit extreme. They are out of the economic mainstream, it isn't considered as relevant as many other schools in the economics profession.\n\n**Keynesian:**\nThis is extremely broad and they don't really agree on as much as you would believe. I'm going to explain center-left keynesianism, something like Paul Krugman or Christina Romer. \n\nOpinions on free market:\nGenerally positive but they believe that there are many market failures that need correction. The main market error is called 'sticky prices', basically a free market can only work properly if prices change according to the circumstances, keynesians believe prices don't really change much so the free market is deficient in this regard. Usually believe that free markets cause economic growth which enhances the well being of society in general, although of course there are winners and lossers.\n\nOpinions on the government:\nGenerally positive. The government should correct the many market failures to ensure the free market works correctly. They should also redistribute income to ensure adequate living standards for everyone. Basically, you let the free market create economic growth with the government ensuring the free market works properly AND equality. As a side note, Keynes considered himself a classic liberal, he didn't really think his ideas were abolishing capitalism or replacing it but ensuring that it worked in the best possible way. \n\nOpinions on recessions:\nRecessions occur because people are buying less (well obviously). Another way of saying this is that people are buying less because prices are too high, if only prices could decrease recessions wouldn't occur. But prices won't decrease because the free market isn't efficient enough to decrease all the price of all products simultaneously. So the government steps in, if no one is buying things then the government buys them and gives them to the people directly. Alternatively the government could decrease interest rates, by doing this it's cheaper to get a loan so people have more money to spend and the recession is averted. When the recession is over the government does the opposite, instead of spending it has to increase taxes to get a surplus and increase the interest rate.\n\nAdvantages: A decent balance between free market and government. The world more or less followed keynesian economics during 1945-1973 and those were the best years for the developed world. They put forward solutions to solving recessions.\n\nDisadvantages: No one wants to follow keynesian policies because they are hard. It's difficult for a government to have a surplus during the boom years as no one wants to be prudent during a boom, it's difficult to run big deficits during a recession because everyone is scared they are about to become the next Greece. Keynesian economics are attacked for promoting irresponsibility during recessions and excessive caution during a boom.\n\nWhy they think no one listens to them:\nPoliticians and society are too stupid to run a surplus during good times and a deficit during a recession. This is like personal finances 101 but when a recession hits everyone prefers to talk about how everyone has to tighten their belt, tighten the belt into a depression that is."
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bi48f5 | why are knots in wood so difficult to cut and/or drill through? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bi48f5/eli5_why_are_knots_in_wood_so_difficult_to_cut/ | {
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"Wood is made up of long fibers. The wood's \"grain\" is determined by the direction that these fibers point in. The direction of the grain affects how the wood feels to cut - cutting *across* the grain chops the fibers in half, whilst cutting *with* the grain separates them from each other.\n\nYou need different tools to make these cuts - [crosscut saws](_URL_1_) and [rip saws](_URL_0_), respectively. \n\nA knot is formed when the trunk of a tree grows over where a branch used to be before falling off. The grain of the wood changes significantly around a knot - up to [90 degrees](_URL_2_).\n\nSo when you cut into a knot, you wind up encountering all sorts of different grain directions, and your saw is going to behave poorly *somewhere* in that cut."
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"https://en.wikipedia.org/wiki/Rip_saw",
"https://en.wikipedia.org/wiki/Crosscut_saw",
"https://en.wikipedia.org/wiki/Wood#Knots"
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5yvyt9 | why does our whole arm go numb if we hit our elbow in the wrong place? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5yvyt9/eli5_why_does_our_whole_arm_go_numb_if_we_hit_our/ | {
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"Because you're hitting the ulnar nerve, which runs down the length of the arm, all the way to your ring-finger and pinky. ",
"Your nerves start at your brain and spread out from there like branches from a tree. If you cut (hit) a large branch, it effects all the smaller branches and twigs spreading out from it."
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g06p3g | how did the people who mummified the bodies in egypt thousands of years ago, knew that their methood will preserve the bodies for so many years? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/g06p3g/eli5_how_did_the_people_who_mummified_the_bodies/ | {
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"It was trial and error. There are some examples of badly preserved mummies. The Egyptians used trial and error to build pyramids also. There are some really shoddy attempts.",
"Science. Research. Experimentation. Trial and error from generations of mummifiers (the funeral directors & embalmers of their time). I'm sure they tried different treatments on animals and then checked on them periodically to see which method was working the best with the least amount of decay over the years/decades. Mummification wasn't just for the kings and ultra rich. They are finding mummies of more common people. Of course the procedure, wraps, and mummification wasn't of the quality of what you'd find for the rich people. Even back then you got what you paid for. Did they know the bodies would last for several thousands of years? Probably not, but you never know what they hoped for. It might be written down somewhere though. Maybe try asking this question in r/egyptology. Someone over there might know.",
"Ancient egyptian civilization started making mummies around 2700 BC and continued for over 2000 years - so they absolutely did know that mummies could last for thousands of years.\n\n[_URL_0_](_URL_0_)",
"Bodies really can only decay so much, and most of that happens within a few weeks. And as such the general gist of mummification working or not can be worked out through experimentation (and reasoning to expedite the process) within a historically very short period of time. Over time all of this got refined, but this was all after the \"proof of concept\" got throgh.\n\nLocal climate also heard greatly helped: while spontaneous mummification and actual mummification are obviously different processes, both are greatly helped by a dry atmosphere.\n\nFinally, you know how you don't hear about all the planes which dont crash? Roughly the opposite is true for mummies: any unsuccessful mummy (granted, this had more to do with storage than the initial process if we are talking about the long run) eventually decayed and people thousands of years later would not find anything of note from it."
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2im896 | how is it that so many guitar makers can manufacture guitars that look identical to fender stratocasters, fender telecasters and gibson les pauls without being sued? did fender and gibson not patent those designs/models? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2im896/eli5_how_is_it_that_so_many_guitar_makers_can/ | {
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"That's correct. By the time Fender, for instance, got around to applying to make its guitar body shapes a trademark, the courts rejected the application on the grounds that no-one buying a guitar could tell it was a Fender from body shape alone.\n\nThe full decision in the US Fender case is [here](_URL_0_).\n\nAnd the Gibson is [here](_URL_1_).",
"Patents only cover technological advancements & even those only last for a few years. After a patent expires, anyone can copy a device. Even more, the patent application **contains the secrets of the device**. Both the Stratocaster & the Les Paul have been around since 1952 so any technology that was in them has long since fallen out of patent protections.\n\nThere's some claim for **trademark** violations, but those can be much more difficult to enforce when looking at something like the shape of a guitar. If you look at the clones, they've all got some minor variation in the shape of the body or the headstock or the location of the controls that makes it different enough to be legal.\n\nAlso keep in mind that a company might sell the same product under different brand names (like Fender using Squire as their value brand). It's also entirely possible that the companies copying Fender designs are actually paying for the right to do so."
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"http://ttabvue.uspto.gov/ttabvue/v?pno=91161403&pty=OPP&eno=246",
"http://www.ca6.uscourts.gov/opinions.pdf/05a0387p-06.pdf"
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66z4w9 | why aren't clear gun magazines more common in the military? | Don't you want to see how many bullets you have? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66z4w9/eli5_why_arent_clear_gun_magazines_more_common_in/ | {
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"Metal is more durable than whatever plastic you would make the magazine out of. It's stronger and dents instead of cracks. Also you can just have a slit in the side to see the bullets.",
"The plastics in clear gun magazines have several problems, some that come to mind are as follows:\n\nThe plastics have lower strenght than the stamped sheet metal.\n\nThe plastic can degrade over time and have limited field service life\n\nThe plastics are flammable and can burn\n\nAnd \n\nAt elevated temperature conditions, the plastics tend to deform and fail\n\nPlus, they need a totally different manufacturing technique.\n\nI have actually observed the stamping of small arms magazines, plastic, transparent magazines require complex injection molding techniques. ",
"In the military (at least in the infantry) you are trained to count your rounds as you fire. I did have a couple magpul mags while deployed with the window, but I always depended on my count rather than trying to peer through a small window and try to count the rounds. Plus I had a tracer every 10 rounds."
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jr8qg | can someone explain the uae to me? | How does it have so much money, princes and palaces? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/jr8qg/can_someone_explain_the_uae_to_me/ | {
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"It's a small country on the Arabian Peninsula, about the size of Austria.\n\nThough much of the Arabian Peninsula is desert and most of that is controlled by Saudi Arabia, most of it is also unpopulated.\n\nIt's a different political setup than were're used to in North America and Europe. It's probably the closest, in how it's politically arranged, to Switzerland, but that's a rough comparison. Here's what I mean:\n\nThe UAE is a series of seven small countries, or \"Emirates\". They are united, and they are mostly Arab, hence the name United Arab Emirates. Each Emirate has an emir, or monarch, who has absolute authority in his Emirate. The Prime Minister of the UAE is elected by these seven Emirs.\n\nThe federal government of the UAE is responsible for the following foreign affairs, security and defense, nationality and immigration issues, education, public health, currency, postal, telephone and other communications services, air traffic control, licensing of aircraft, labor relations, banking, delimitation of territorial waters and extradition of criminals.\n\nThese are the only functions of the national government, and the Emirs retain all other responsibilities in their own Emirates.\n\nThe largest (in size and population) of the Emirates you may have heard of: Abu Dhabi and Dubai.\n\nThe reason there are so many princes is because it is, essentially, a super-nation of seven monarchies, each with its own royal families. The reason it has so many palaces is because it has so much money. The reason it has so much money is because it has so much oil.\n\nIts oil reserves are estimated to be the sixth largest, by nation, in the world. Oil and the wealth it has produced is also pretty much the only reason anyone lives there in the numbers that they do. In the Middle Ages, this was an area mostly under control of nomadic people. The population of the country before the discovery of oil was about 2% of its current population. Furthermore, most of the population, about 75%, lives in the five largest cities, all of them built mostly on the strength of oil revenues.\n\nPersonal note: I've talked to some architects who've worked in Dubai. The horror stories about projects abandoned mid-completion in the face of the economic crisis that began in 2008 are pretty interesting.",
"It's a small country on the Arabian Peninsula, about the size of Austria.\n\nThough much of the Arabian Peninsula is desert and most of that is controlled by Saudi Arabia, most of it is also unpopulated.\n\nIt's a different political setup than were're used to in North America and Europe. It's probably the closest, in how it's politically arranged, to Switzerland, but that's a rough comparison. Here's what I mean:\n\nThe UAE is a series of seven small countries, or \"Emirates\". They are united, and they are mostly Arab, hence the name United Arab Emirates. Each Emirate has an emir, or monarch, who has absolute authority in his Emirate. The Prime Minister of the UAE is elected by these seven Emirs.\n\nThe federal government of the UAE is responsible for the following foreign affairs, security and defense, nationality and immigration issues, education, public health, currency, postal, telephone and other communications services, air traffic control, licensing of aircraft, labor relations, banking, delimitation of territorial waters and extradition of criminals.\n\nThese are the only functions of the national government, and the Emirs retain all other responsibilities in their own Emirates.\n\nThe largest (in size and population) of the Emirates you may have heard of: Abu Dhabi and Dubai.\n\nThe reason there are so many princes is because it is, essentially, a super-nation of seven monarchies, each with its own royal families. The reason it has so many palaces is because it has so much money. The reason it has so much money is because it has so much oil.\n\nIts oil reserves are estimated to be the sixth largest, by nation, in the world. Oil and the wealth it has produced is also pretty much the only reason anyone lives there in the numbers that they do. In the Middle Ages, this was an area mostly under control of nomadic people. The population of the country before the discovery of oil was about 2% of its current population. Furthermore, most of the population, about 75%, lives in the five largest cities, all of them built mostly on the strength of oil revenues.\n\nPersonal note: I've talked to some architects who've worked in Dubai. The horror stories about projects abandoned mid-completion in the face of the economic crisis that began in 2008 are pretty interesting."
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3qdg1s | how does electricity work in big bodies of water e.g. if lighting hits the ocean will it hurt you in the water, if so how far does the danger extend in the water? | My title doesnt make much sense and im sorry i dont really know how to word the question im trying to ask if you put an eletric current in the ocean e.g. how far will that current travel? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qdg1s/eli5_how_does_electricity_work_in_big_bodies_of/ | {
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"I think this is like the 5th time questions similar to this have been asked tonight, is there some publication that came out talking about this?\n\nWater is a fairly good conductor and, like most good conductors, most of the current is kept on the surface of the water. Even though salt water is a better conductor, the current in both salt water and fresh water will spread out to around 20 feet (~6 meters) (in fact, salt water will probably keep more of the current on the surface).\n\nIf you're underwater, you're probably not going to get shocked anywhere near as much. You would have a much bigger shock if you were sticking out of the water since lightning is more prone to strike a taller object, especially a conductive one (air is a bad conductor compared to you), before traveling into the water.\n\nA bigger concern would be the shock wave from the sound. The sound from lightning underwater can reach 260db a meter away from where the lightning strikes. Where sounds above 130db can cause acute hearing loss, 260db would be devastating.",
"Water is actually a terrible conductor. It's the salt and impurities that carry a current. Like all conductors though, salt water does have some resistance which is comparatively quite high as opposed to say copper. The distance the electricity will travel will mostly depend on the salinity of the water but usually about 20 or so and will tend to travel farthest along the surface."
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1vves2 | how does the google authenticator work? | I've been using it for a while to authenticate with Google itself, but I've now just added another site to it and I'm intrigued. How does it work?
_URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1vves2/eli5_how_does_the_google_authenticator_work/ | {
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"First off, there's a security construct known as a MAC, message authentication code. It's basically a way to verify that a given message is both correct (verified, nothing lost or altered) and who it came from (authentic). What is a message? It could be any data at all. Your name in text, your picture in jpg form, or even the **current** **time**, conspicuous bolding to be revealed later.\n\nThere is HMAC, wish refers to an implementation that uses what's known as a hash to accomplish this. A hash is just a mathematical algorithm to churn up the message and a private key together to provide this verifiable and authentic message. Data and the private key go in, a hash comes out. A hash is just a number.\n\nWhen you link up a Google Authenticator account, a private key is generated for you for that service, hopefully in a secure manner so other people don't also have it. So you have it, and the service has it. What you see on your screen are hashes^*. What is the message? Literally, the **current** **time** (actually, current 30 second block of time).\n\nContrary to popular belief, internet connectivity isn't even really required to make this whole thing work. As long as the private key can be communicated to your device in advance (the setup you did twice), and both the server and device can agree to use the current time, your phone can be completely disconnected and this will still work.\n\n^* technically not, just portions of hashes, as six decimal digits doesn't really provide a great hash in and of itself, but these are part of a two-step authentication, so it's not awful. Consider the \"lost authenticator\" hash with many more digits."
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3hz4lw | why are all the planets sperical? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hz4lw/eli5_why_are_all_the_planets_sperical/ | {
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"Gravity works in all directions, and everything pulls on everything else. Stuff bunches up and tends to move toward the center.\n\nEven if a planet just magically popped into existence shaped like a pyramid or cube, the sharp edges and pointy bits would collapse and fall toward the center of gravity."
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43g53p | why do americans need to register for a party before they can vote for it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43g53p/eli5_why_do_americans_need_to_register_for_a/ | {
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"This only applies to primary or caucus elections. This is the part where there are many candidates from a single party, and the voters of that party vote to decide which one candidate should represent the party. You can only vote in the party you are registered to (in most places, I think NH has a weird rule but don't quote me on that) for these initial elections. In the actual general elections, you can vote for anyone. ",
"Because if you like republicans, you would vote for the democrat you think would have the worst chance and vice versa. Then put in the republican you like later, sort of stacking the cards.",
"The primaries aren't government elections, they are internal to the political party and only decide who will run on that party's ticket for the actual election. ",
"This varies state to state. Vermont for example does not have you register for a party, just to vote. For each election you are given three ballots (Dem, Rep, and Indep) and you fill out one and return the others.",
"Primary elections are not normal elections. They are related to the party system which is currently dominated by the Democrats and the GOP. \n\nThe party system does not come from the Constitution. The first President, George Washington was not a member of a party and actually thought they were damaging to democracy. But over his time, parties formed around controversial issues to match something like the democracy in Britian. \n\nToday, for better or worse, parties are central to the US political system and active voter participation is seen as important. In other places like the UK, the choosing of a parties leader varies from party to party and is often very closed off from the general electorate, as to some extent, it is a internal party matter. You can still vote to keep a particular party out of power if you dislike there choices. \n\nMany states do have open primaries, and rules are set by the states. This means rules on who can vote, whether you need to be a party member or not and if you can vote in one or more of the parties primaries are set by the state so expect variation between where you live and other states. \n\nTLDR: political parties are not part of the Constitution so are run by themselves and rules vary from state to state."
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1j0wre | how are laws created, and why are they so difficult to change? | My daughter asked me this and I couldn't come up with a satisfactory explanation. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1j0wre/eli5_how_are_laws_created_and_why_are_they_so/ | {
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"I'm going to assume you are in the US so here's a basic overview on how it works at the state/federal level, tailored to your daughter. A member of the legislature (a group of men and women elected by the general population) suggests a new law after researching an issue. The rough draft (aka bill) is presented to a small portion of the legislature (a specialized committee) who looks it over and fixes any typos/errors/things they don't like. Then the bill is sent to all of the legislature and they decide if they like it or not. If they like it, it is then sent to the executive branch (the governor/President), where there is a final yes/no check. If the executive person likes it, it becomes law. Now to make or change a law, you need to get a majority of all of the people in this process to decide they want to change it. It's like voting on what game to play at recess, except with hundreds of people who don't like each other that much.\n\nEDIT: Also, watch this with her _URL_0_ and I'm sure you're a very capable parent and it's good to see you go the extra effort to ask for help in explaining a concept you're not too comfortable with.",
"You really need to sit down and watch Schoolhouse Rock. "
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4p21mn | why do airport code names follow no particular pattern? | Why aren't airport names just the first three letters of the name of the city in which the airport is located?
For example the name of the airport in New York is JFK, which is fine, I guess, but then the real name for IAH is George Bush Intercontinental airport. Then the name for Vancouver International airport is YVR? Why is there a "Y" in there? It makes no sense?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4p21mn/eli5why_do_airport_code_names_follow_no/ | {
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"They used to be shortened versions of the airport name. But with only 3 letters, they started running out of codes and had to do some very arbitrary things. In addition, sometimes cities get a new airport, and the old one already had the obvious abbreviation.\n\nTrivia fact: O'Hare is ORD because it used to be called Orchard Field.\n\n[More info here.](_URL_0_)",
"Many names actually do make sense. \n\nMost (all?) Canadian airports start with Y. Vancouver is YVR -- Y (Canada) VR (Vancouver). \n\nJFK - because the airport is named JFK airport. \n\nIAH -- International Airport Houston\n\nMany airports have short names that make sense, but lots of the \"make sense\" ones ran out, so sometimes airports get more random or obscure letterings. \n\n(FYI there is also a different 4 letter naming scheme that is actually used by pilots and air traffic and official stuff like that) ",
"IAH = International Airport Houston. \"George Bush Intercontinental\" was named that *well* after \"IAH\" was assigned; the reason it couldn't be HOU was that HOU was already assigned to another airport in the Houston area, and it can't be similar because there's a rule that you can't assign similar identifiers to nearby airports (to prevent confusion).\n\nYVR = Canada, VancouveR. When the FAA was designing the system, there were a few three-letter ranges set aside. Canada claimed all codes starting with Y; the Navy got codes starting with N; the FCC said \"you can't start with W or K because those are for radio stations.\" Incidentally, that's why Newark is EWR: can't use \"N.\"\n\nOften, the odd codes are old names. JFK changed its code from IDL (IDLewild, which is what it used to be called) to JFK, but that's very unusual. O'Hare was ORcharD Field, so it's still ORD. Other times, it's because of other airports in the area taking the logical name, or because the logical name is used by someone else somewhere else in the world. ",
"With three letters from a 26 letter alphabet, there are only 17576 possible airport names. \nThe airport where I learned to fly was in Rifle, Colorado, and it's name was RIL. \nI used to fly to nearby Grand Junction (GJT). \nAs /u/Concise_Pirate mentions, once we get to 17 thousand or so named airports, we're going to start having some runway in Hartford Connecticut named \"XKQ\" because all the \"good\" names have been taken. \n",
"Here are some reasons airport codes might seem cryptic:\n\n* it is an acronym (CMH is Columbus Municipal Hanger)\n* the official name of the airport is obscure or has been changed (Louis Armstrong Airport (MSY) in New Orleans used to be called the Moisant Stock Yards)\n* even the smallest municipal airport gets a code, and there aren't enough enough letters (how many airports are San something?)\n* the city name changes (Ho Chi Minh City's airport is SGN)\n* language differences (Tokyo is NRT for Narita)\n* certain letters are reserved...N is for US Navy airfields, so Newark has to get by with EWR\n* a smaller, older airport has the \"good\" name...Hobby, not Bush, got HOU in Houston\n* when two large airports are withing 200 miles, they have to start with different letters (HOU/IAH, DCA/IAD)\n* Canada just up and decided all they airports would start with Y, to make them easy to distinguish from US airports\n* the airport isn't always where you think it is...Cincinnati's airport (CVG) is actually in Covington, Kentucky\n"
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424xo9 | is it possible for a light source to make things darker? | Hey all,
I have a decent understanding of physics, i did it at University (years ago!). Im very confused though and I'm not sure how to explain myself here...
Is it possible for a light source to make the general room darker? I'm talking fractions here. I mean that if a room as 1 billion (theoretically just made up a huge number)watt illumination and you throw a 30 watt illumination in there would it make the room darker as a whole?
I take it there will be interference between light waves, is there a theoretical max light value where any added light will have no additional value?
I may have units wrong, ive been at pub all afternoon.
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/424xo9/eli5_is_it_possible_for_a_light_source_to_make/ | {
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"If you look at a laser, then yes! Well not just a laser, pretty much any light source. When 2 coherent sources' light waves overlap eachother, they can form either constructively or destructively. Constructively - the brightness of the resultant wave increases, Destructively - a dark fringe is created. If you check the comments [here](_URL_0_), you can immerse yourself in some more awesome light related stuff.",
"No. Theoretically you could cram an infinite number of photons into any given space. Past a certain point you'd end up with a black hole made entirely out of energy, though."
]
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2hs49h | why does a seed to a fruit bear a whole plant that grow the fruit instead of just the fruit? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2hs49h/eli5_why_does_a_seed_to_a_fruit_bear_a_whole/ | {
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"Fruits are used as a way to coax animals into transporting and dispersing seeds for a plant to effectively reproduce. If their seeds just fell to the ground, the resulting cluster of plants would be so thick that nothing would grow properly. By enticing animals to eat the fruit and, therefore, spread the seeds, it is ensured that the offspring of a plant are spread out rather than clustered.",
"\nThe seeds contained in a fruit that grows on a tree contains the genetic material of the whole tree, not just the fruit-component of the tree. \nWhen you plant a seed, you allow for the genes to be read and copied so the development of the organism can begin. \n\nFruits are actually means for the tree to make sure its species won't disappear: they're sweet, colorful, tasty.. so that animals are attracted to them, manipulate and eat them. The seeds they contain are often either not ingested or not digested and left on the ground at a certain distance of the original tree, assuring perennity of the species.\n\n\nWe're lucky seeds don't bear just the fruits; if it was true everywhere, humans would bear quite a weird mix of genitalia instead of babies..! x) "
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8n76wx | what causes the sudden sharp shooting pain in your chest that literally lasts for no more than 30 seconds? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8n76wx/eli5_what_causes_the_sudden_sharp_shooting_pain/ | {
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"You need to elaborate, most people don’t get this, it could be anything from acid reflux / indigestion to a Cardiovascular issue, how often does it happen and is there anything specific you have noticed that causes it?"
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djnb0b | how were vhs tapes mass produced? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/djnb0b/eli5_how_were_vhs_tapes_mass_produced/ | {
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"Pretty much the same way that you would duplicate a tape at home: Read the video from one tape, and write it onto an empty casette.\n\nHowever, they were using automated machinery for this process. Since reading and writing tape also degrades the quality, they were using a very high quality video tape as a master to read from, instead of another video casette.",
"If you mean how was the recording transferred onto the tape, I believe they used a process where a master tape was pressed against the blank tape, and locally heated to transfer the recording. This can be done at higher speed than just playing the master and recording it onto the blank! \n\nI think the master had to be \"negative\", eg recorded with a reversed magnetic field.",
"They used high speed dubbing machines. Here's a video of [it in action](_URL_0_).\n\nThey work basically the same way as a home VCR, it just works a lot faster. A high quality master copy is read at a very high speed, then a bunch of rotating magnets transfer the signal continuously onto huge reels of blank tape that's running at the same high speed. That tape is then trimmed and spooled onto the reels inside the cassettes. It's a deceptively complex process. Tapes are a lot more expensive to manufacture compared to optical discs. Hence why they quickly disappeared after DVD players became affordable."
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3703z6 | why is liquor and beer cheaper when you pay cash at a lot of liquor stores? | Here in Texas, we have a Spec's liquor store and they always offer a discount when you pay with cash or debit. I was just curious as to why this is beneficial to the company vs having customers pay with a credit card. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3703z6/eli5_why_is_liquor_and_beer_cheaper_when_you_pay/ | {
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"As a retailer, you pay the credit card companies a fee per transaction. Either a percent or a flat $0.xx fee. (with debit cards, the transaction fee is usually borne by the card holder).\nAlso there could be a delay between swiping and actually receiving the money. Debit or cash, they have your money immediately."
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2ox17i | why wouldn't game developers make exact copies of good old games but with better graphics? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ox17i/eli5_why_wouldnt_game_developers_make_exact/ | {
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"Well thats actually something that has been happening a lot in the game industry recently. There have been quite a few remakes / remasters. This year alone we got a re-releases of the last of us, kingdom hearts 2 and 4 Halo games so it's a thing that is happening.\n\nI think though that you more asking why don't they just create whole new games that just play like the old ones right? Well because people would get mad and not buy them. Consumers want to see some sort of improvement or progression when the see a sequel or newer version of a game. If you're not going to change the game in some way(for better or worse) why should they buy it? Many consumers would just stick to playing the older games.",
"Sometimes they do; I recently finished playing the remakes of the original Monkey Island games, with all the same gameplay but improved graphics and sound. But with the developers' commentary turned on they mentioned how much of a pain it was to re-port certain animations and whatnot for the modern version. So I'd imagine it comes down to economics: the cost of doing a graphics-only remake isn't much less than creating a whole new game as a sequel, and doesn't make up enough in revenue.",
"Sometimes it does happen, but there are lots of reasons not to. In no particular order:\n\nUpdating the graphics takes time and money. If the game is getting released on a new system, then you basically need to make the whole thing again from scratch.\n\nUpdating *only* the graphics has the potential to put off consumers who aren't already fans. If the gameplay and features aren't up to date as well, then sales are going to be hurt.\n\nFans *already* own the game. If graphics are the only addition, then they don't really need the new one. Yes, some people will buy it, but the less dedicated fans won't bother.\n\nThe updated versions might already exist. Since you mention X-COM (a great game, btw), you should probably be aware of the OpenXcom project. Fans have remade the game, fixed a lot of the problems, improved many aspects, and have encouraged modding which adds a massive amount of new content and improves graphics. There's literally no reason for someone to spend money on a new version when they can get the fan made update for just the cost of the original. \n\nEdit: And finally, a re-release has the potential to cut into the sales of any new releases in the series. Going back to XCOM, they just released a new game a few years back. If they also released a brand new port of the original at the same time, people might have bought that instead of the new one. ",
"It is offtopic, but HD remake of HoMM3 was just recently announced. See _URL_0_"
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69m1xc | how do copyright laws work for the bible and other religious texts? | Also, in the modern day, where does the money from the purchase of a Bible go? Historically, when there was only the Catholic Church in Western Europe, I can understand a church monopoly on these texts but what about when more denominations were made? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/69m1xc/eli5_how_do_copyright_laws_work_for_the_bible_and/ | {
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"The original Bible (the Old Testament in Hebrew and Aramaic and the New Testament in Koine Greek) is way too old to be copyrighted. Copyright only lasts until 70 years after the author's death. Many translations of the Bible, like the King James Bible, are also not copyrighted for the same reason.\n\nIn the case of books that are not copyrighted, anyone in the world can print some copies and sell them- the person or company that prints them is the one that gets the money.\n\nNewer translations, like the NIV, can still fall under copyright. In that case, the person or company that does the translation owns the copyright. ",
"There is no copyright on the bible, it's in the \"public domain\", which means anyone can freely print and sell a bible however they like. That being said, you can take a bible, put stuff around it (create a \"derivative work\") and *that* can be copyrighted. So for example, if you wanted to make a bible where you provided notations and historical thoughts along with each passage, you can successfully use copyright to prevent other people from reproducing and selling your version.",
"The original Biblical texts are thousands of years old, and although we don't have the originals any more, the copies we do have are still centuries old and so way past even the most ridiculous copyright terms that they're absolutely, definitely in the public domain.\n\nMore recent *translations* of the Bible may be under copyright protection, but the copyright holders are usually quite generous: after all, it's expected that people will want to reproduce Biblical texts and use them to \"evangelize\". The publishers might stipulate what they allow: for example, I have a copy of the New International Version which states:\n\n > The copyrighted material may be quoted and/or reprinted for non-commercial purposes up to and inclusive of one hundred (100) verses without express written permission of the publisher, providing the following credit line appears with the material being quoted: Taken from the HOLY BIBLE, NEW INTERNATIONAL VERSION © 1973, 1978 by the International Bible Society.\n\nThe money pays for the translating and printing of the Bible. This is a huge undertaking that can take years, often involving hundreds of people. Just take this small excerpt from the preface of the NIV, explaining the process of translating the Old Testament:\n\n > The translators also consulted the more important early versions -- the Septuagint; Aquila, Symmachus and Theodotion; the Vulgate; the Syriac Peshitta; the Targums; and for the Psalms the *Juxta Hebraica* of Jerome. Readings from these versions were occasionally followed where the Masoretic Text seemed doubtful and where accepted principles of textual criticism showed that one or more of these textual witnesses appeared to provide the correct reading.\n\nIn other words, a team of translators and theologians had to cross-reference several ancient texts written in ancient Hebrew, Aramaic, Greek, Latin and so on, and where they differed, they had to find a way to figure out which was most likely the correct version. That kind of work doesn't come cheap."
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5aofy9 | how do authors make money selling books on google play for $0.01? | I was browsing the Google Play Books app on my phone and noticed that there were a few books in the "recommended for you" section that only cost 1 cent. These were novels with hundreds of 4.0+ star ratings, and ranging between 100 and 300 pages.
How are these sellers making a profit? On Amazon, it makes sense since the $0.01 books come with "$3.99 shipping" costs, so the seller can try to ship the items in bulk for less than that and keep the shipping profits.
The only thing I can think of is that perhaps this is a way for authors to draw readers in and hopefully convince them to buy their other books? If so, I would have expected the "attention grabber" books to be much shorter though, as opposed to full length novels. As a consumer, I'm very happy with the incredibly low prices. I'm just curious as to how the authors make money from this service without either ad or shipping revenue. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5aofy9/eli5_how_do_authors_make_money_selling_books_on/ | {
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"you also see these on steam with games at 1 dollar or a few cents. \n\nFirst of all you have to understand that once passed to digital distribution the duplication cost is near zero (basicaly the cost of electricity) so it costs nothing to distribute new copies of a work thats already been created and edited. \n\nNow the price of the book is set by varios factors.\n\nPopularity : if the book failed to sell many copies and the author/distributer have given up on it and has no more sales expectations he might lower the price so atleast anyone thats interested can read it.\n\nPublicity : If the author has a few books out and his older works which have already made their money back plus profit that are no longer in demand he can lower their price as a publicity stunt, so i get people to read my new book by giving away the old ones which already made their money back. \n\n",
"A lot of the books with lots of good reviews but super low prices are actually books in the public domain -- things written 50+ years ago (depending on your region, there's much more in the public domain in eg Australia than America) that are no longer protected by copyright. This means anyone who wants to sell it can do so without needing permission. You can grab the Bible, or stuff by Virginia Woolf and Charles Dickens, spend 10 minutes sticking it in an ebook file, and sell it for 1 cent, 10 cents, 50 cents, a dollar. They're famous books people are likely to buy and it takes almost no effort. If it only takes me 10 minutes to stick *Frankenstein* on the Play Store, I can charge 1 penny for it, and if 1,000 people buy it then I just made a dollar a minute. Spend an afternoon doing this and you can get a good chunk of change.\n\n\n\n"
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6v7y8t | what's the actual, non-conspiracy-theory explanation for why world trade center 7 fell? | Googling this leads me down so many rabbit holes. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6v7y8t/eli5_whats_the_actual_nonconspiracytheory/ | {
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"It had a huge gash torn out of it by one of the other towers. That included some support structures. \n\nFurther damage from fire led to the tower being too heavy for the remaining supports to hold up. And the gouged portion basically \"tugged\" the standing portion down when a crucial pillar (79) couldn't hold up further. \n\nEdit: had a wrong piece of info. Added the exact failure point for the major collapse. ",
"My source (Wikipedia) says the nearby North tower of the WTC destroyed it. Debris and Fire struck the WTC 7 building and eventually caused it to collapse",
"A very, very tall building next to it collapsed, with a lot of debris hitting 7 WTC. This debris started fires that eventually led to the structural collapse of the building. ",
"_URL_1_ \n\nThere is a gash starting at the top of the building going at least 10 stories down from a tower falling into it. The entire south face of the building is smoking and fires are raging on at least few floors. \n\n_URL_0_",
"According to both the FEMA and NIST reports, the building collapsed due to uncontrolled fires causing some beams to expand and push a main girder off it's seat, causing the center of the building to collapse. \n\nApparently there was no water pressure at the WTC so firefighters couldn't actually do anything.",
"I highly reccomend taking the guided tour at the Memorial if you get to NY NY. Ask to go with Eduardo if you can."
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6vbpqb | the 1939 decision of erie v. tompkins | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6vbpqb/eli5the_1939_decision_of_erie_v_tompkins/ | {
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"Federal courts don't have the power to create their own \"common law\" when hearing a case under diversity jurisdiction. Instead they have to apply the relevant law of the state they sit in.\n\nSo, imagine a federal law and a state law that both have the word \"bank\". \n\nIf you get sued in federal court about that federal law, the Court can decide that bank includes credit unions. \n\nIf you're sued in state court under the state law, the state court can decide that bank doesn't include credit unions.\n\nIf, later you are sued on the state law in federal court based on diversity jurisdiction (meaning they sue you in federal court because the parties are from different states) then the federal court must use the state court's interpretation of bank, not it's own."
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3524c7 | what is happening when i turn my head too quickly and get that sharp pop in my neck, followed by a painful warm tingle? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3524c7/eli5_what_is_happening_when_i_turn_my_head_too/ | {
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"I've gotten it too - feels like you've done yourself some serious damage doesn't it?? I don't know a verified exact reason, but a friend of mine is a physio and he says that it's simply a pinched nerve - your neck has twisted in such a way that one of the nerves has gotten pinched by the vertebrae or something else.\n\nThe result is hot tingly feeling. Not nice.",
"I get neck spasms, and that happens when I turn my neck too quickly but they last all day and my I can't move my neck. Is that what you mean?",
"I have actually seen some specialists on this matter, since I've had this happen to me since I was a kid. \n\nIn my case at least, what was happening is that I was pinching nerves in the spinal column. Now, I also have a bulging disk in that location, and some minor back problems, but it stands to reason that even without those extra conditions, if you turn your neck too fast in the exact wrong way, you could also be pinching nerves. \n\nI would encourage you to see a specialist if this happens to you a lot. I did physical therapy for a while, along with some continual exercises, and they've really helped both cut down the pinching and my back issues in general.",
"This is a type of nerve pain. It shouldn't do any permanent damage but if it happens often get it checked out.\nSource: I was diagnosed with fibromyalgia (over active nerves) and my doctor explained that this exact feeling is nerve-related.\nAlso nerve-related: if you feel like someone dropped an egg full of painful heat onto your head that drips down the sides of your brain... Weird things those nerves.",
"Physiotherapist here.\n\nThere's some talk of it being a pinched nerve. Does painful sensation follow a dermatomal distribution? _URL_0_\n\nI'm guessing by the descriptions it doesn't, so I'll continue on.\n\nYou may be experiencing a sympathetic response to the cavitation in the neck. A cavitation (or \"cracking\") is a rapid release of gasses from the joint and is thought to affect the capsuloligamentous structures of the neck (hence the basis of manipulation for spinal pain). At every level of the spine we have our \"regular\" nerves for sensation and movement, but we also have nerves for the sympathetic nervous system (the fight or flight system). \n\nYou are likely having an effect on the sympathetic ganglion (nerves) in the neck and experience this sensation around the area.\n\nPs don't keep cracking joints on your own! There isn't great research behind this but theoretically you can hypermobilize the joint that keeps cracking as the movement takes the path of least resistance and keeps cavitating the same level in the spine. This may be why you are getting this response in your neck.\n\n(Even though it feels good - all you feel is the reflexive relaxation of tight muscles, but long term it's only tightening them more!)",
"OMG, I get this too, but I get a massive headache for a couple moments that gradually goes away on the back and lower part of my head where the pop occurred. Always wondered what that was all about."
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6n14aa | what program do famous game developers use to make their games and how much time does it take? | I am very interested in this please answer in detail
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6n14aa/eli5_what_program_do_famous_game_developers_use/ | {
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"They use a lot of programs. 343 Industries uses Maya for its modeling and texturing, Visual Studio for frame analysis and templating, Cryengine for visual scripting and 3D videos, Autodesk for project management and scripting, the list goes on and on. \n\nAny one person is unlikely to know all of these programs to the depth of detail that is required to make a AAA game, and the employees will have either a BFA in Graphic Design or Game Development, or a BS in a variety of Computer Science, Programming, or Computer Engineering. **Almost everyone who works at an industry leading game development company will have a Bachelors or higher in a relevant subject.** The people who don't have these kinds of degrees generally do not get hired by these companies.",
"Game development is mostly done in a programming language C++. Programming works by writing text files using any text editor(like notepad on windows), then compiling them(gnu c compiler is a program that could compile your C++ program). Programming languages are basically just like any other language, they have certain syntax and allow you to tell computer what to do. Programming languages however aren't directly understood by your computer, you need to compile them into .exe's first.\n\nAdditional tools you need, you typically make them as well, like level editors. However, writing code/programming has some automated systems to make your life easier. The most obvious such tool is an IDE. It's basically upgraded Notepad that highlights certain code elements, checks for syntax(compare to spell checkers, but for programming), and allows managing multiple files related to the same program. Also, graphic and sound design have their own programs, those I don't know about.\n\nDevelopment takes anything between 1 and 1,000 years of work.\n\nThere's also concept of game engine. Game engine is a thing that does the basic skeleton tasks, so game developers optimally only need to attach their levels and characters and such things to it for game to be ready, with game engine handling drawing on the screen, checking mouse movements, keyboard, keeping track of where everything is, and generally just providing a way for developers to easier communicate to computer what they want to see. For example, two objects colliding in a game world maybe should result in something happening, but first you'd have to detect if collision has happened. If you make a game from scratch, you'd have to do math like trigonometry to check distances between objects and then tell which distances count as collision etc, but game engine typically has that part so you can just tell it what to do when objects collide.",
"Let's say I want to make Pong. \n\n**DIY**: I write pong in C++, a programming language, and I have to write out the code that checks for key inputs first. Then code that will talk to the graphics card and draw a box of pixels where I need it to. Then code that will update every few milliseconds and refresh the positions of all the boxes. Then code that will take the inputs from the keyboard and add or subtract from the position of the player's paddle every frame. Then code that will move the ball around every frame. Then code that will check if the ball has come into contact with the edge of the screen or the player's paddle. Then code that will send instructions to the audio driver to play the sound of the ball bouncing. Then write... etc etc. \n\nVery complex and time consuming, but it allows me to write quite an efficient game (not taking up more processing power or memory than necessary)\n\n\n**Middleware**: I'm still writing pong in C++, but I've licensed a third-party tool that handles the collisions for me - so instead of manually checking if the ball has moved close enough to the edge of the screen, I just ask this tool to check it for me. The same can be done for inputs and sound, so while I'm still writing a lot of code, the 'standard' stuff has been taken care of. \n\nSlightly easier and quicker, but still involves writing most of the behind the scenes stuff to connect it all together. Still fairly efficient.\n\n\n**Game Engine**: I open up Unity and drag and drop some sprites for the boxes and paddles. I write a script (smaller piece of code) that talks to the engine's built in physics system to see if the ball's touching the paddle, and then call on the engine's audio system to play a sound file if it has. \n\nEasiest and quickest, but usually means you have to work within the engine's limits (and sometimes means using more memory/processing power)\n\n---\nMost modern games use either of the latter two: Overwatch and GTA V are written mostly by their developers with some middleware thrown in. PUBG and Lawbreakers both use the Unreal Engine (4).\n\n"
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9yaqvi | in american college football, why do so many quarterbacks clap to signal when to hike the ball instead of a verbal queue? | You figure that college stadiums are louder so a verbal "hike" or silent count would be better. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9yaqvi/eli5_in_american_college_football_why_do_so_many/ | {
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"It is often so loud down on the field that anything verbal is hard to get across reliably. A good clap is louder and easier for the center to discriminate from all the other noise. Plus it provides a visual cue to the guys far away (wide receivers etc.). ",
"Sometimes they do use verbal cues, but often those verbalizations can contain instructions to change the play on the fly based on the Quarterback's 'look' at the defense.\n\nSometimes it's absolute nonsense, in a typically vain attempt to lure the defense into encroachment/offsides penalties."
]
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[],
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2w077q | why are there technically two china's | Basically the title but to explain more, why is there a Republic of China and a Peoples Republic of China and why isn't there just one full china. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2w077q/eli5_why_are_there_technically_two_chinas/ | {
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"China had a civil war after WWII. The communist side (People's Republic) won on the mainland, and the other side (Republic of China, the previous national govt) retreated to Taiwan, where they are still in power.\n\nBoth claim to represent all of China and think the other one is illegitimate and evil. They aren't friends."
]
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2yjiq7 | how decimal place infinity is larger than counting number infinity | Late night tv leads me to the Science channel where it's an episode about Infinity and the study of infinity. I understand the conflict about scientists battling if the universe is finite or infinite. But they presented a bit where maths people proved that there are varying levels of infinity. How? Isn't infinity just infinity? The way it was presented that DECIMALPLACE infinity had more points than COUNTINGNUMBERS infinity confused the hell out of me. If both just go on with no end, how is one bigger than the other? Was I right when I actually was 5 saying "Infinity +1!" to win an argument? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2yjiq7/eli5_how_decimal_place_infinity_is_larger_than/ | {
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"No, you are still wrong when you said infinity plus one. However, there are different infinities.\n\nNatural numbers are the set from {1,2,3,....}. Let's say this has \"infinite\" elements. So far let us assume that infinity plus one is something logical. \n\nNow, the whole numbers {0,1,2,3,...} . This looks like there is one extra number. So it has infinity plus one elements. \n\nBut wait. Let's create a new set called whole+1 numbers. Add one to each element in whole numbers. Now we have {1,2,3,4....} which is the same as natural numbers. This proves that infinity plus one is same as infinity. \n\nThis infinity is given the symbol aleph 0 (read aleph naught). \n\nNow let's move on to rational numbers. [Here](_URL_0_) is an interesting proof of why there are exactly the same number of rational numbers too. \n\nThat was less exciting than expected. So, let's see the real numbers. At this point I would recommend to watch this [quick video](_URL_1_) (2 mins). This explains how there is another bigger infinity. This is called aleph 1. \n\nEDIT: Infinity is neither a number nor a digit, it is a representation. Therefore, you cannot say zero point infinity. It is just as ridiculous as saying zero point orange, or zero point banana. ",
"There's a proof (Cantor's diagonalization argument). Before we start, a couple things: we're only going to focus on the decimal numbers between 0 and 1, meaning any number that has a (possibly infinite) decimal expansion in [0, 1]. Examples are: 0.5, 0.11…, 0.12345…, and so on. If there are more decimal numbers between 0 and 1 than there are counting numbers, then there have to be more decimal numbers on the whole real line than there are counting numbers. The other thing: how to tell if one set is bigger than another set. If you can line up the elements of your first set and match them up with the elements of the second, then they're the same size. Otherwise, the set with elements left over is bigger. Example: if you have two hands and two gloves, you match one glove to each hand - > you have the same number of hands and gloves. If you try with two hands and three gloves, you match one glove to each hand, and you have one glove left over, so the set of gloves is larger than the set of hands.\n\nNow suppose that the set of decimal numbers between 0 and 1 is the same size as the set of counting numbers. (\"There's only one size of infinity.\") Then there's a way to pair them off, one by one. What that means is that I can *index* the decimal numbers: this one is the first, this one is the second, … this one is the 500th, … and I keep going. I'm going to show that there's a decimal number left over. Take the first decimal number. The first digit after the decimal point is 0, 1, 2, 3, 4, 5, 6, 7, 8, or 9. If it's a 2, I take 3. Otherwise, I take 2. That's the first digit after the decimal point of my *new* number. Keep going like this: for the 2nd (or 3rd, or 1000th) place after the decimal point, I take a digit that's *not* the digit in the 2nd (or 3rd, or 1000th) place of the 2nd (or 3rd, or 1000th) place decimal number.\n\nFor example, if the first three decimal numbers in my pairing are 0.6, 0.1234567…, and 0.777…, then my new decimal number starts: 0.232, and I keep adding digits.\n\nNow I've built up a decimal number, digit by digit, that's not equal to any of the decimal numbers that I counted off. So I missed one! That's a contradiction: I never had a way to pair off the decimal numbers with the counting numbers in the first place, so my original assumption was wrong. Therefore there are more decimal numbers between 0 and 1 than there are counting numbers.\n\nYou actually can't do this with an \"infinity + 1\". If you take the counting numbers, and the counting numbers with one extra element (say, -1, for simplicity), then you can pair them off easily: -1 with 0, 0 with 1, 1 with 2, and so on. Each element of the counting numbers is matched to exactly one element of the \"counting numbers plus one\", so those sets are the same size. But the real numbers are conceptually tricky, and more exotic stuff can happen.\n\nEdit: Added example for clarity."
]
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[
"https://www.math.hmc.edu/funfacts/ffiles/30001.3-4.shtml",
"https://www.youtube.com/watch?v=A-QoutHCu4o"
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[]
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|
6jrr1e | how come some gifs need a "gifv" link to be viewed, while others work without even a click? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6jrr1e/eli5_how_come_some_gifs_need_a_gifv_link_to_be/ | {
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"Traditional gifs are fundamentally images. The format was not designed for video. It was always an image format, but with the option of having a short series of images to make a little animation.\nBut then people starting using gifs for much more than they were designed for. People started using them for videos. This is really inefficient because each frame is stored as a separate image, where as proper video formats tend to store each frame as a difference from the last one. This means gifs of only a few seconds long can be huge, and take ages to download.\nDespite the drawbacks, people liked the convenience of gifs because they can play in any browser and can be easily embedded into websites, comments, etc.\nThe idea behind gifv is to keep the convenience of a gif, but using an actual video format. Gifv is not actually a specific format, it's just a filename used to inform you that it's a video that's intended to be looped like a gif. A gifv is actually a WebM or MP4 video file.\nGifv is so much better because it can make files over 10 times smaller. Most sites have ability to render images from links, however they don't render videos or can't for various reasons. That is why you can see GIF where ever you can see pictures, but not GIFV and also that is why GIFV is smoother,",
"\n\n\n\n\nI'm no expert, but here's my basic understanding of it:\n\nGIFs are basically a bunch of images lined up and played in order like a flip book. This can make really long GIFs massive in size, which would take ages to load since they have to save every single frame. \n\nGIFV on the other hand is more like an MP4, where it's one image and the next frames are just instructions on what changes. So instead of storing the whole image, if the background of trees is always the same, you can get rid of it basically when saving the files. "
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3l3n6e | what are warrant canaries and what do they do? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3l3n6e/eli5_what_are_warrant_canaries_and_what_do_they_do/ | {
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"Very often, when a service provider is issued a warrant to hand over information about their customers, some aspect of the warrant prohibits them from telling their customers about the warrant.\n\nThe providers _want_ to warn their customers, but the warrant prohibits them from doing so. In order to counter this, they put out statements periodically saying that they _haven't_ received a warrant to search their users. When a warrant does come, they simply don't publish the statement, which allows them to warn the community without violating the terms of the warrant.."
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290poy | how is the landing gear of a plane designed to withhold this much force? | _URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/290poy/eli5_how_is_the_landing_gear_of_a_plane_designed/ | {
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"Why: Because this is a failure mode the engineers specifically design for.\n\nHow: They had to burn off all the fuel and land on fumes, and land with the nose up as long as possible, and still most of the wheel ended up decorating about a mile or two of the tarmac.",
"A major factor is the material. Landing gear is most commonly made from 4340M/300M high-strength steel. Arguably some of the best steel money can buy. It's a grade of steel pretty much designed for this purpose which has a very high tensile strength-- on the order of 280-300 KSI. This means it would take as much as 300,000 PSI of force for the material to yield. Most other metals simply can't achieve that."
]
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"http://youtu.be/iXEuDLcoDv4"
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[],
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ade7kf | how and why does albino-ism occur? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ade7kf/eli5_how_and_why_does_albinoism_occur/ | {
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"text": [
"Albenism, and it requires two parents, who both carry the recessive albenistic gene to BOTH pass that gene on to their child. And that recessive gene is very rare anyway. So it is super unlikely that two people carrying the gene would meet, and even then its only a 25% chance that their baby gets the condition."
]
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366x4o | why do most fast food restaurants specialize in hamburgers and french fries? why isn't there more variety? | If you're in the mood for a cheeseburger and fries, you're in luck because you have your pick of McDonald's, Burger King, Wendy's, Sonic, Carl's Jr., White Castle... the list goes on.
Hot dogs are a well-known and beloved American food too, but off the top of my head the only place I can think of to get a hot dog is Nathan's, and I've only seen a handful of those over the course of my lifetime.
Why is this? How come so many restaurants can serve the same type of food with all that competition? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/366x4o/eli5_why_do_most_fast_food_restaurants_specialize/ | {
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"Tons of places offer hot dogs: street vendors, Sonic, Dairy Queen, and many more regional places. Many places offer Mexican food. Many places offer deli sandwiches. Quite a few Asian places could be called fast food, even if they are rarely drive through. I'd say they have competition. ",
"Hamburgers can be stored for a really long time, such as potatoes, and both are very cheap, easy to make the food. it began based on that preposition and now I believe it is tradition, even though lots of various \"fast food\" restaurants of different kinds mainly foreign food (indian, kebab, sushi, etc) have been sprouting",
"There is lots of variety. \nMcDonalds has the Filet O'Fish, McRib, and Chicken nuggets in addition to burgers. \nBK has rings in addition to fries, and chicken nuggets, fish sandwiches and wraps besides burgers. \nWendy's - chicken sandwiches, wraps, salads, baked potatoes. \nWhite Castle has veggie burgers, chicken and fish, rings or fries. \n\nHot dogs aren't in that much demand. There are a few hot dog chains in the greater NYC area other than Nathans, but business is hard. ex: [Callahan's](_URL_2_) went out of business, but a younger family member just reopened one shop. Others are listed on [Wikipedia: Hot Dog restaurants](_URL_4_) \n\n Street vendors can make a decent living, and every ball park has them. \n\nIf people really wanted them, markets would find a way to deliver and profit. \nMcDonald's [did try](_URL_3_) the [McHot Dog](_URL_0_). \nBurger King sold hot dogs during the 1970s-1980s, but they weren't selling. They recently tried a promotion in Japan for breakfast with [\"classic dogs\"](_URL_1_). \n\nThe only other pressure I can think of is that many fast-food restaurants cater to a large market of children. Franks/hot dogs can more easily get lodged in kid's throats causing choking. Fears by parents might keep sales down, fears of injury might have internal legal teams against them. \n",
"It sells, simple as that. These companies didn't get world famous by offering stuff no one wants, they sell what makes them the most money. I'm gonna assume you're in America, cuz in America that's burgers and fries. FYI a lot of global fast food places serve different things in different countries because the average person in those countries wants something other than burgers and fries. Try googling fast food menus around the world, I'm lookin at stuff like the McLobster, Chicken McDo with Spaghetti, McItaly Adagio Burger (w/ eggplant and almonds), Foie Gras Burger(goose liver), Sprout Surprise Whopper (yup, sprout burger).",
"[ELI5: Why do fast food places sell burgers, but not hot dogs? Burgers and hot dogs always go together outside of fast food places.](_URL_0_)"
]
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[],
[],
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"http://www.rantlifestyle.com/wp-content/uploads/2014/07/picture-1-99-tm.jpg",
"http://everythinghapa.com/archives/12702",
"http://www.callahanshotdogs.com/",
"http://www.businessinsider.com/failed-mcdonalds-items-2011-8?op=1",
"http://en.wikipedia.org/wiki/List_of_hot_dog_restaurants"
],
[],
[
"https://www.reddit.com/r/explainlikeimfive/comments/2z0q0l/eli5_why_do_fast_food_places_sell_burgers_but_not/"
]
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|
1sf5ns | how do front page posts disappear from the front page? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1sf5ns/eli5_how_do_front_page_posts_disappear_from_the/ | {
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"Flat-out disappear? Moderators deleting the post, most likely.\n\nFall from the front page and down the rankings? The formula reddit uses takes into account the amount of time since the post was made, so the longer a post has been around, the more it gets penalized. Additionally, the reddit formula uses the logarithm of a post's karma to rank it, meaning that each additional upvote is worth less than the one before it. Combine the two effects, and all posts will eventually fall off the front page.",
"Imagine upvotes are helium and time is weight. Eventually, the upvotes stop coming in, but the algorithm pulls down older posts."
]
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augk27 | why quadratic equations work to find the graph of a parabola and how factoring works. | I just finished my test on quadratic equations, but my teacher did a great job of helping but not really explaining. I'm really confused please help. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/augk27/eli5_why_quadratic_equations_work_to_find_the/ | {
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"The beloved quadratic formula is a tool for finding the roots (points where the value of the function is zero) of a second degree polynomial (a parabola). \n\nMany polynomial equations can be expressed as the product of a set of first-degree polynomials (linear equations). Factoring polynomials to that state will make it easy to calculate roots, as where any first-degree factor is equal to zero, the product of all factors (aka the complete higher order polynomial) will equal zero.",
"Specifically the quadratic formula is derived from using a technique called completing the square on the equation ax^2+bx+c=0 and then solving for x. Showing the work on that is a little more eli14 or eli15 (usually taught in integrated math 2 or algebra 2 if ever). "
]
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btbrav | why is getting to the bottom of the ocean so exponentially difficult? | "The Trieste dove to 35,797 feet in 1960, and Cameron hit a slightly shallower point in the trench at 35,756 feet in 2012.
Vescovo's team plans to go deeper. It thinks it has identified a spot that could take the expedition to 35,859 feet"
& #x200B;
Why is only 60 feet extra the goal? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/btbrav/eli5_why_is_getting_to_the_bottom_of_the_ocean_so/ | {
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"The deeper you go, the heavier the water above you is. So the pressure at these depths is extreme. Building a craft to withstand still remains a challenge.",
"The deepest part of any ocean is the Marianas Trench. The bottom of the trench isn't flat, so somewhere along that trench is the deepest spot in the oceans. No one knows specifically where that spot is, so each dive to the bottom tries to find the deepest bit but it looks like they haven't quite managed it yet"
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35kork | could gravity be an effect of time dilation, as opposed to the other way around? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/35kork/eli5_could_gravity_be_an_effect_of_time_dilation/ | {
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"You are one smart motherfucker. Seriously, you are, and I am not being facetious in the slightest. Between 1905 and 1915 or so, Einstein was asking himself the same questions, and that was how he got from special relativity (1905) to general relativity (1920-ish). It took him a damn long time, so the fact that you're even close to where he was is worthy of praise.\n\nWhat turns out to happen is not that \"gravity is caused by variations in time.\" You were very close, but you missed it by a bit. It's actually \"gravity is a variation in spacetime curvature,\" which is close but very different.",
"Let me try explaining. More experienced redditor, please do correct me if I am wrong so that I can understand this better myself and stop me from spreading misinformation.\n\nSo we exist in space and time, and we always move at a constant pace, be it space or time.\n\nThis means if you are in the middle of nowhere with no mass nearby, you move at a constant pace towards the future (time).\n\nIf you move fast enough relative to another object, your time will slow down relative to that object, because you spend some of that pace moving through space instead of time.\n\nNow, mass bends space time for some reason, so instead of moving forward in time 100% of the time, you move slightly in space towards that mass (since the mass curved it), hence gravity aka mass attract to each other, and why your time slows down near massive objects.",
"The problem here is in considering the different effects of spacetime on different parts of *the same object*. One object is traveling at the same velocity in all its parts. The difference in gravitational force is going to be incredibly tiny across the width of a small comet or asteroid -- like, immeasurably slight. Also, an object of huge or of tiny diameter, with the same mass, velocity, and distance (by center of mass) is going to react the same way to a massive object (star, black hole, whatever), even though the larger diameter means it will have a larger (still tiny) difference in gravity at nearest and furthest edges with respect to the attractor.\n\nI'm no physicist either, and I love your willingness to make sense of what looks at first like a counterintuitive idea, but from my also-slight grasp of the ideas in play here, I can't see how that would work.",
"Ok, I've only had 2 hours of sleep so this may lack proper punctuation, but I'm pretty sure my mind is right on this:\n\nI went back to that post you made in /r/physics and I think it's spot on. I just don't think you understood his answer, but the opening paragraph of his response pretty much answered your question.\n\nI guess a way to look at this is to not assume that anything you said makes sense. I'm not being mean here at all. I'm just poking holes in your logic that help me with understanding. Now, if gravity is an effect of time dilation, then what causes time dilation in the first place? Are you saying that there is naturally variances in time without anything causing such things, and these variances lead to dilations that lead to gravity? That, to me, hardly makes sense. The reason being that you'd have to have *something* - > *time dilation* - > gravity. But that could just be the wrong interpretation on my part and I would need to think of very very large objects for when this is appropriate\n\nBut still, it doesn't make much sense. Without any kind of field or any kind of effect on an object, no matter the size, you're arguing that there are significant enough variances of time over bodies such that they actually experience what we know is gravity. To me, it kinda seems like something similar to \"chicken or the egg\" but not as complete. \n\nIf you can come up with a model such that time actually effects the space around it that would allow gravity to actually be created, then I guess it would make more sense. But I don't know.\n\nNow having said all that, let's try working with your model here. Let's propose some wild shit:\n\nNow let's say gravity is some kind of result of time dilation. I can't really see that unless gravity is more like an after image. So let's say we have that comet and large star you were talking about earlier and everything you said fits. Now let's also say that for t = 0, there's 0 gravity. I'm modifying your system a bit just for this point. At t = 0 there's no gravity and obviously no noticeable variances in time. Now, for time 0 < t < t-inf we obviously have some time so that delta t and delta t' become our variances in time on different sides of the large object. \n\nNow, over delta t and delta t', the gravity produced wouldn't be instantaneous gravity. There's actually no effect of gravity during these intervals but there IS gravity experienced. This gravity at delta t would simply be from delta t + 1. So, \"current\" gravitational effects are really caused by variances in time but not of time that just happened. More like, projected time. So the implication here is that at some point there just wasn't any gravity but as time went on, gravity was produced\n\nSo I guess the way I see it in your model is that time had to be going for quite some time before gravity could be experienced and it all happens like a hamster on a wheel where the speed of which the hamster moves determines how fast a ball moves across the ground or something. If the hamster is going super fast, then the ball moves at a decent pace but if it's going slower, the ball pretty much doesn't move.\n\nso I guess **tl;dr**\n\nI can only see what you're saying if time actually happens before gravity in an event like time being the man pulling a heavy metal ball on the ground. When the man is close to the ball and begins to move out, the ball doesn't move. As he moves out even more and applies force, then the ball slowly moves and his force determines how fast it moves. In thhis scenario the man is time and the ball is gravity. \n\nIf you're saying that the event of gravity and time are instantaneous then I don't see how the answer you got in /r/physics doesnt work. But if you're saying that time happens *pause* then gravity happes and can be observed....and that the way to explain gravity at any given point is to look at the variances of time before that point...then I guess I can see what you mean."
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4euqnx | what's up with these commercials on the radio telling me to buy gold because the market is going to crash? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4euqnx/eli5_whats_up_with_these_commercials_on_the_radio/ | {
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" People are trying to sell you gold. So they are trying to scare you into thinking that traditional investments are a bad idea and gold is safer. \n\n Advertisements come from companies that are trying to make money, not companies that are trying to give away their profits to you. ",
"No, it's not a scam per se, but really there's no point putting your money into something like gold unless the market does actually crash, at which point even if you do have a stock of gold it won't help you that much because how the hell are you going to exchange it? Would banks be giving out free wheelbarrows?\n\nIt's just a commercial, designed to get your money into their company.\n\nGold prices tend to be fairly static when compared to other things, so people like investing in it as a security blanket of sorts.\n\nIt only has worth because we ascribe it worth. Used to be because it was rare, shiny and made decent jewelry that doesn't tarnish like silver.\n\nNow? The same reasons still apply. It's not really as rare as it was back during the gold rush years, but we also use it a lot more in electronics, so there's a bit more demand as well.",
"It is believed that during a recession, gold becomes a more attractive investment option, and so the price of gold tends to increase relative to other investments (not necessarily go up in value, but might not decline as much). If true, the reason is probably more psychological than anything (perception of gold as safer since it's an actual tangible item that can be stored).\n\nSince they are a company trying to sell gold, they are suggesting that a recession is imminent so that you buy gold before the recession occurs. They would be making a profit from the sale of gold to you now. Regardless of whether the recession happens, or what happens to gold prices, they have already made money from the sale, which is their goal.",
" > Is it a scam? Why am I hearing these commercials so much? Do any of you have insight?\n\nWhen gold is worth a lot of money, there's lots of ads offering to sell it. When the value for gold drops, there's lots of \"we buy gold\" ads...\n\nThe end result is they buy low and sell high. "
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3k0gjd | why is graffiti hard to read, and why do they tag trains? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3k0gjd/eli5_why_is_graffiti_hard_to_read_and_why_do_they/ | {
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"That's the direction that particular art-form has gone. Since it's very much about lettering, the letters have taken a life of their own and become more and more elaborate. Partly it's also an in-group thing: you are part of the cool kids and the inner circle if you can decipher the graffiti code.\n\nAs for painting trains: they offer a large continuous canvas, are stored in secluded rail yards, yet come out during daytime for people to see. If people could paint elaborate pieces on buildings on the main street, they would. But since someone will surely see them and call the police, they rather sneak into the rail yard and paint in relative solitude.",
"Check out style wars on youtube if you want to see some of the original New York graff artists in action. You can learn why they write on trains straight from the artist's mouths."
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2qbhvq | how do we know for sure that cancer and other deceases aren't caused by being constantly exposed to small radiations from electronic devices and 3g, 4g, wifi, lte, bluetooth-signals? | I am in no way trying to be ignorant. I am certain that scientific studies has drawn some kind of conclusion, but how do we know *for sure*?
If you think about it, there are rarely times where you can enter a room and not being in the way of some kind of signal. It just crossed my mind, how heavily has this area been studied?
How do we know that testicular cancer is not a consequence of an electronic device constantly receiving signals from various sources?
Best regards, and merry christmas! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qbhvq/eli5_how_do_we_know_for_sure_that_cancer_and/ | {
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"Wifi is just radio waves, a well researched technology we've been using for a long time. Cell phones emit a small amount of radiation, but studies by the WHO have shown that even extended exposure is safe.",
"The signals you mention are non-ionising electromagnetic fields and yes we are constantly in contact with them in the \"modern World\", so to speak.\n\nIonising particulate (or X-ray) radiation is a much different and potentially dangerous thing.\n\nIt would take too long to write it all down here. Just do a quick Wiki search for ionising radiation.",
"Simple, cell phones/wifi/etc all emit either radio- or microwave radiation. These two types of radiation fall under the umbrella of non-ionizing radiation. Other types of radiation in this category are infrared and visible light. Ionizing radiation includes UV, x-rays and gamma rays as well as radiation from nuclear reactions. \n\nNow, what separates non-ionzing from ionizing? Well the former can't knock electrons from atoms and thus can't make ions. Now to cancer, cancer is a genetic mutation where the DNA that controls cell reproduction is damaged and runs uncontrollably. In order to have this happen, you have to mess up the bonds in the DNA, which means you need enough energy to strip away electrons. So its physically impossible for non-ionizing radiation to cause cancer. The worst thing that going to happen from cell phones use, etc.. is your face is going to get a little warm.",
"For a start, cancer predates humans. For example, dinosaurs got cancer. Lots of modern day animals in remote locations get cancers that are very similar to human cancers, yet they are not exposed to any (man made) radiation.\n\nIf we look at human history, we can find plenty of evidence that our ancestors suffered from the same cancers that we do. They didn't have cellphones.\n\nSo from this we can conclude that modern technology cannot be the sole or primary cause of cancer.\n\nGoogle/apple/samsung report phenomenal sales of cellphones and other wireless devices every year. If these devices caused cancer, then there should be a corresponding worldwide spike in reported cancer cases. ",
"A danish study over 20 years, found absolutely no correlation between cellphone usage and cancer rates. Other long-term studies came to the same conclusion, and even cellphone network towers have never been seriously linked to cancer rates. \n\nHere's a few results from long term studies: _URL_0_\n\nWhich concurs which what other posters here said, that RF waves simply aren't strong enough to change or break DNA."
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4bqx63 | why are we able to put our hands through liquids but not solids? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4bqx63/eli5_why_are_we_able_to_put_our_hands_through/ | {
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"Liquids can be very complicated but are still liquids. The molecules in liquids are fairly short and do not bond much with each other. I am putting in these qualifiers. That is because water is special and has polar properties. Colloids can be very complicated.\n\nIn solids there is much more bonding going on. Molecules can be very long chain. They physically confine each other from movement because they are so large.\n\nSolids include a huge number of molecules and types of bonds. There are ionic bonds and covalent bonds. Salts are solid but their structure is vastly different from covalently bonded molecules.\n\nThe simple answer is that liquids are composed of molecules which are small and do not bond with each other much. Solids are made of molecules which can be very large and interact with each other to form solids.",
"Think of a ball pit. The balls can move around freely, so it's easy to move around in the ball bit. Now imagine all of the balls had velcro on them. They'd stick together and it would not be easy to move around in the pit at all.\n\nThe distinguishing characteristic of a liquid and a solid is that in solids the molecules hold onto each other strong enough that they don't easily slide past each other, like the velcro balls. In liquids the molecules can move around pretty freely like the normal balls."
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3d7b7u | how chromecast starts playing where netflix last left off even when netflix isn't playing yet? | Even when the Chromecast is unplugged/disconnected, it still picks right up although its source isn't playing.
edit: sorry for the tag, I came from /r/DestinyTheGame. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3d7b7u/eli5_how_chromecast_starts_playing_where_netflix/ | {
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"Chromecast doesn't need to stream anything from the source device unless you're specifically playing content from it like locally stored video. For things available online like Netflix or Youtube, the Chromecast streams it directly from the internet and your device only functions as a remote control to tell it what to play."
]
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6i0ehk | i need to understand hmm model but the docs are too technical for me. | I need to work with Sound recognition. But just explain the HMM model and what is special about it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6i0ehk/eli5_i_need_to_understand_hmm_model_but_the_docs/ | {
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"A Hidden Markov Model is a way of modeling a system in which it's assumed that some part of the system is *unobservable*, or hidden. Imagine you're watching your friend prepare food and you see that he doesn't cook it long enough, and then you eat the food and get food poisoning. The result that you get food poisoning makes sense given what you saw during the food preparation, because you know undercooked food has a higher probability of making people sick. But now imagine a situation where you weren't around to watch the food get prepared; you just ate it and got sick. In this case part of the process was not observable, but you can still infer what most likely happened in that unobserved process based on the results - because the food made you sick, and undercooked food is more likely to make people sick, the probability that the food was undercooked is higher than it would be otherwise.\n\nSpeech recognition is essentially about analyzing a particular sequence of events - in this case individual sound phonemes - and trying to match those sounds up with words from a language. The observed information is the individual sounds, but there's a lot of unknown information, like what context the speaker was in and what intent they're trying to convey. \n\nImagine I have a voice controlled device and I say \"Set the volume to two\". If we only look at the sounds I made then there's no way to know whether I said \"to two\" or \"tutu\" because phonetically these are the same. However, we can make a guess at what my intent in the sentence was, even though that intent is hidden. If we know from previous examples of observed speech that words involved with setting the volume are often followed by some numeric volume level, and are not often followed by references to clothing worn by ballerinas, then it's possible to guess that it's *more* likely that I said \"Set the volume to two\" and not \"Set the volume tutu\".\n\nDisclaimer: I have no experience using HMMs for speech rec. I just have a basic understanding of what HMMs are in general, and this is my best guess of how they might be useful for recognizing speech."
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2qpa8z | hawk's are said to have eight times better vision than humans. what does this mean exactly? | How can I understand this better? If I see through a lens and blure my vision to half, I see nine times worse than an hawk? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2qpa8z/eli5_hawks_are_said_to_have_eight_times_better/ | {
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"\n\nTheir acuity is 8 times better. This means if you can the texture on the wall from 1 foot they can see it from 8. You can still see the wall at 8 but you don't get all the detail a hawk would. \n\nSince you can't really do an eye check on a hawk and ask for feed back the number is really an estimate based on how we observe them (they can spot a mouse in a field at x distance) and their eye structure (Narrower field of vision, more eye cells, larger eyes, less blood vessels, and a second fovea).\n\n[tl;dr of the why: hawk eyes have more pieces giving them better vision](_URL_0_)\n",
"I could say that they are more sharp or can focus better, but that doesn't explain it very well. To understand how their eyesight is vastly better, let me try an example. \n\nThere is a grain of sand on the empty, flat floor. You bend down and look at it, you can see it. You know it's there. You climb up a table now, the grain diminishes, but is still visible; you are able to make out a dot that doesn't merge onto the rest of the floor. Now you go to the second floor and look down on the grain of sand, if you didn't know it was there, you wouldn't see it. Now you go to the third floor and look down, even if you knew the exact location of the grain of sand, and you looked dead right at it, you wouldn't pick it up with your eyes. Everything just looks.. The same. Everything is just floor.\n\nIn a way, hawks can still make out the difference at greater distances and heights than we can; while I'm unsure about the veracity of the \"nine times\", it is definitely true that they can still see much better and sharper as such. It's like their eyesight has better pixel count or something, they can make out details we don't. Many people mistake it as that they can \"zoom in\" but that's largely not the case, they don't need to zoom in, they can just make out small details better. "
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9tgtyx | what is bread? | I've been eating this stuff since I was 3. It's about time I figured out what it's up to. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9tgtyx/eli5_what_is_bread/ | {
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"What you need is flour and water. The most common flour is wheat flour from milled wheat grains. You can use flour from rye, barley, corn, oats, sorghum, millet, rice etc\n\nThen you heat is som way where a oven or a a frying pan is the most common. Then you have bread.\n\nAlmost all bread used some leavening agent to produce bas bubbles to make is soft and fluffy. The most common is yeast, baking soda and sourdough microbes. If a leavening agent is used you need to let is rise before you bake it.\n\nThen you add stuff for taste and structure. Salt, fat, sugar, milk, egg, spices etc. Exactly what is added and what leavening agent and flour is used depend on the bread.\n\n\n"
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27sca1 | when a transgender person is put in a gender specific institution such as prison, how is it determined which facility is appropriate? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/27sca1/eli5_when_a_transgender_person_is_put_in_a_gender/ | {
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"They assign them according to birth sex. No matter how long they have identified as the other. If they have had surgery they assign them according to their reassigned sex. Ones that have not has surgery are at high risk in prisons so they are generally \"administratively segregated\" from the general population. And it really depends on what prison system they go to. Some are even allowed to continue hormone therapy. ",
"It highly depends on where they are. The following are the most common, and are presented in the order of best practices first.\n\nSome states and countries base it on what is the identity they've been living under. Others do it based on what their genitals looks like. Others do it based on the gender of the birth certificate. In addition, they are often placed in 'protective segregation' which is basically solitary confinement under the guise of there being no other safe option."
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a8gwp0 | why is anaphylactic reaction so violent and harsh to humans? what sense does it make as far as biological advantage? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a8gwp0/eli5_why_is_anaphylactic_reaction_so_violent_and/ | {
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"Anaphylaxis is caused by an antibody called immunoglobulin E overreacting to what it thinks are infections and causing excess histamine to be released which in turn can cause severe reactions possibly leading to anaphylaxis. - _URL_0_",
"Anaphylaxis doesn't offer a biological advantage\n\nA normal allergic reaction is when your body detects a threat and then sends the army to battle stations to fight it, only to realize it's a pretty weak enemy\n\nAnaphylaxis comes about when your body detects a \"threat\" and goes \"Oh shit! Launch the nukes! Kill it with fire!\" but it turns out nukes are ineffective at removing this poor rogue protein but they're the best you've got so you keep hitting it with more and hurting yourself until you die\n\nNot everything our body does has a biological advantage, some things are disadvantageous but don't kill you before you breed, or they're only disadvantageous when taken to the extreme but helpful in small doses(being a sickle cell carrier gives malaria immunity)"
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64ogyp | in high energy physics, how come the sonic boom is nowhere to be found? | Particles at/near light speed are traveling very fast- well above Mach 1. So, where are the sonic booms? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/64ogyp/eli5_in_high_energy_physics_how_come_the_sonic/ | {
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"Sonic booms are made when something moves through the air faster than the speed of sound and creates shockwaves.\n\nInside a large particle accelerator like the Large Hadron Collider, it's about as close to being a perfect vacuum as you can get. There's no air so no shockwaves or even any sound to speak of at all.\n\nSecondly, the particles are *way* too small to result in any sort of large noise."
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32pii8 | after his predecessor's death, how is the "newest incarnation" of the dalai lama found? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32pii8/eli5_after_his_predecessors_death_how_is_the/ | {
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"Using someone called the Panchen Lama, part of who's job it is is finding the next Dalai Lama. When the Panchen Lama dies, one of the duties of the Dalai Lama is to find the Panchen Lama. This is how it has been for around 700 years. The two of them, finding each other and recognizing each other, again and again."
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5n25l9 | how do sea creatures change depth rapidly without getting pressure sickness? | Not sure if pressure sickness is what its called.
I'm referring to when divers dive down a to certain depths, they need to wait and acclimatize to the depth before proceeding up or down.
How do animals like whales and other deep sea creatures surface so fast without exploding? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5n25l9/eli5how_do_sea_creatures_change_depth_rapidly/ | {
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"What you're referring to is decompression sickness - it only happens when ascending. You can descend as fast as you want. Decompression sickness happens because gas dissolves in your blood at high pressure and comes out when pressure reduces. This happening too fast can cause problems. \n\nWhales have a lower risk of decompression sickness because they're only using one lungful of air at atmospheric pressure. There isn't much gas to dissolve. Scuba divers breathe high-pressure air for a long time, meaning that more gas will dissolve. \n\nThat said, whales that surface too fast do get decompression sickness ([source](_URL_0_))."
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942yd0 | how do buildings decay to such a horrible state? (image in post) |
How are buildings actually able to decay this much? How do abandoned buildings eventually decay into this condition? What actually happens to cause them to fall apart like this? Like what's the actual process of how a building goes from being abandoned to looking like this?
Images for reference of what I'm talking about
_URL_0_
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/942yd0/eli5_how_do_buildings_decay_to_such_a_horrible/ | {
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"Much like our bodies and pretty much all things in existence buildings need maintenance, defenses, and check ups. Because much like human bodies there are chemicals and elements that attack buildings and destroy them. Water and temperature can cause wooden elements to rot. Humans throwing rocks or general weather can break windows. And brick and concrete are susceptible to many chemical attacks if not treated, maintained, designed, and constructed properly.",
"It's usually a combination of vandalism and weathering.\n\n(some) Humans have this tendency to leave their mark on created objects that don't appear to be maintained -- which causes them to look even less maintained. And then you've got leaks and openings where nature can come in and accelerate the deterioration.",
"In addition to what others said exposure to the heat of the sun, rain or snow damages seals on windows and roofs. Water gets into the cracks and caused steel to rust and corrode. Wood gets damaged, rots or becomes desirable for termites. Creating more openings for water to get in and create habitat for mold. The moisture damages the concrete or grout. Eventually it falls apart",
"The fancy scientific word for this is \"entropy\", which is a measure of disorder -- or a measure of how little energy is available to do work. It's sometimes called \"time's arrow\", because the entropy of the universe as a whole always increases with time. Order breaks down, energy becomes more evenly distributed -- and when all the energy in the universe is spread out uniformly, no more work can be done because work is done when energy flows from areas of high concentration to areas of low concentration.\n\nA newly-built structure has low entropy. It wants to increase its entropy so that all its bits spread out evenly. We can only reverse this process by doing work on the building, using our own energy to decrease its entropy again.\n\nHow it works is surprisingly simple: there is only one way all the parts of a building can be arranged to make a perfect building; but an almost infinite number of ways those parts can be arranged to make an *imperfect* building.\n\nEvery time something happens -- the wind erodes parts of the stonework, termites start eating away at the wood, the rain washes off protective paintwork, a branch falls off a nearby tree and smashes a window -- parts of the building are slightly rearranged. And simply because there's an infinite number of ways to rearrange them to increase disorder, entropy is virtually never going to decrease. Thus entropy increases, and the building starts to crumble."
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8l0u8m | why is it wrong to test pulse with a hand on the chest, and what makes the wrist/neck so accurate? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8l0u8m/eli5_why_is_it_wrong_to_test_pulse_with_a_hand_on/ | {
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"It’s easier to feel a pulse from a vein that’s closer to the skin. The neck is one of the best if not the best place to take the pulse, as it’s an artery, and has lots of blood flow. Regarding putting your hand on the person’s chest: If the individual needing their pulse taken is heavier, the heart is behind more flesh/fat, etc, and that can make it harder to feel the pulse. There can also be other issues, like the appropriateness of putting your hand on a stranger’s chest, especially a woman. ",
"It's not wrong to listen to somebody's heart to get a pulse. It's actually a widely used measurement called the apical pulse. It's also how you get a heart rate on infants.\n\nPeripheral pulses are not more or less accurate. They're just easier.",
"There are multiple locations on the body where a pulse may be sensed. Peripheral pulses, such as radial and pedal pulses, offer some diagnostic information about the strength of peripheral circulation (and potentially, circulation distal to an injury) where such circulation could be compromised. Additionally, taking someones pulse bilaterally, such as simultaneous radial pulses on both arms, provides comparative information which can help diagnose injury or medical condition. Conversely, a carotid pulse is always going to be stronger than peripheral circulation, and so is used to check for the presence of circulation as a primary diagnostic measure, or when peripheral pulses are weak or undetectable.",
"It is appropriate to take an apical pulse for infants and adults on certain medications. It's not wrong, just only used for certain situations.\n\nEdit: measuring apical pulses require the use of a stethoscope.",
"Not so much accuracy but ease of access. To take from their chest your likely going to have to strip their upper clothes off and perhaps move their breast out of the way if they are a well endowed woman or extremely fat man.\n\nWhereas for wrist pulse you just hold their wrist.",
"The central pulse (eg the carotid pulse) is usually more accurate than the peripheral pulse (eg the radial pulse). However for ease the peripheral pulse is preferred as it is easier to do by the bedside and less likely to cause the patient any form of discomfort. "
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30oy3l | people who regularly use eli5, why didn't you just google it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/30oy3l/eli5_people_who_regularly_use_eli5_why_didnt_you/ | {
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"ELI5 why salt is so salty when i have a cold.\n\nGoogled that today with no answer.\n\nQuestion is a bit high-brow for askscience.",
"I'm on here just about every day, and I see it happen quite a bit. (Maybe that's just a self-reinforcing bias, though.)\n\nA lot of the time it's obvious that they didn't search before submitting or use Google. I'll copy and paste their question into Google, and the answer will literally be the first result, explaining their question in an ELI5 manner. Other times if it is a topic that won't have an ELI5 answer, I just use Reddit's search bar, and voila! The question has often been asked at least once before.\n\nIt may just be me, but it seems like some people are too lazy to do the legwork to find an answer to their question, so they post here. It's not that they can't understand the topic they ask about, it's that they're not willing to take the time to learn about that topic.\n\nThis isn't to say that all ELI5 questions are the result of laziness. There are certainly concepts that are complicated and need \"dumbing down\" to help become understandable. It's just hard to keep perspective that what may seem like an obvious question to you may not be obvious to everyone.",
"Some people like the human touch that comes from asking a real person. Googling something is less personal, never sparks an online discussion, and may actually be useless if your question is really specific or too complicated for the answer to be readily understandable. \n\nIf it bothers you, remember that you are not being paid to answer the questions, so it's not like lazy people are doing you any harm. ",
"When I've posted its been for feedback and discussion.. Not so much as something I was too lazy to google..",
"Why didn't you just google the answer to your own question?",
"Because Google can give you the right answer, but it can't give you fifteen shitty made-up answers from people who know nothing about the topic.\n\nELI5: Why are people's eyes different colors?\n\n*\"My cousin talked about this once. From what I remember it has to do with how much butter you ate when you were a baby. Other dairy products too, but mostly butter.\"*",
"The problem with typing it into Google is that Google isn't really a respecter of persons. The first articles that usually come up are from Wikipedia or academic journals. Reddit is great is it is full of experts from so many different backgrounds that no matter what question you have, there is someone who truly knows the answer enough to explain it in a simple way.",
"Cause Google doesn't give you karma.",
"Hmm I dunno, perhaps Google has the [answer.](_URL_0_)",
"ELI5 isn't really for getting answers. ELI5 is for browsing by 'new' and laughing at agenda motivated, snarky, 'questions'.\n"
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7y0xdw | why is it our throat that gets ‘affected’ and signals our body when we are thirsty? | Dehydration affects our entire body, and our throat is, as far as I know, merely a pipe that tunnels water to our system. It makes sense to me that we feel the emptiness of our stomach when we are hungry, but the throat feels rather odd. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7y0xdw/eli5_why_is_it_our_throat_that_gets_affected_and/ | {
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"Mucus created in your sinuses drips into your throat causing bacterial inflammation.\n\nSource: I imagine myself playing a doctor on TV"
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ajsvd8 | why do prostate cancer survivors live longer than the average person? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ajsvd8/why_do_prostate_cancer_survivors_live_longer_than/ | {
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"I'd guess this is a result of correlation not equaling causation. My guess is that to have prostate cancer detected, you'd have to have health care that covered preventative care. Ok, so that rules out many lower income men and perhaps men from less developed countries. Keep in mind, many men with prostate cancer have a very slow growing form and will never know they have it. It comes to light during their autopsy. ([_URL_0_](_URL_0_)) \n\nSo, I suspect that to have prostate cancer diagnosed in the first place, you'd have to have factors (employment, income, developed country etc.) already going for you that would place your life expectancy slightly passed that of the average male worldwide. Does that make sense?",
"Survivable prostate cancer tends to appear in older men, so their life expectancy is already somewhat higher. Also, a group of cancer survivors can be expected to have a longer life expectancy than a group that includes people who die from cancer. "
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3re2k8 | why do american football teams not pass the ball more after the snap? | So I saw this video on Reddit the other day of an amazing touchdown _URL_0_ and I was wondering why after the snap or once the ball is thrown to the receivers is the ball not passed more? If the offence is allowed to block defenders then surely passing or offloading the ball to keep it in play would gain players more ground over time or in the case of receivers putting in switch passes to keep the ball alive. I know that this will increase the likelihood of a fumble, but there must be more advantages than disadvantages. Has this ever been tried in a game I.e. A more running and passing style of play like rugby? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3re2k8/eli5_why_do_american_football_teams_not_pass_the/ | {
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"It is very, very risky, and you can only lateral backwards, so anyone who is about to tackle you will just tackle that guy instead, and you'll usually get less yards than if you just held onto the ball. ",
"In American Football, once the ball has passed the line of scrimmage (where the play starts), it can no longer be passed forward. You can pass the ball sideways or backwards, though. Such a pass is called a \"lateral\".",
"The opportunity cost of a turnover in American football is much much higher than in rugby.\n\nYou'll notice that teams only try a bunch of laterals in desperate situations like in the video you just watched. It almost always fails.\n\nOne exception is that you might occasionally see a single lateral down the field if a team runs the hook and lateral play, but I haven't seen anyone try that one in years.",
"Just FYI, the amazing touchdown you linked shouldn't have counted. The ACC ruled they were at least 4 missed calls on that play. The referees of the game have been suspended for doing a terrible job.",
"In American football, they are only allowed to throw one forward pass per play, and even then it is only allowed on a normal offensive play (e.g., not on a kickoff return) and only from behind the line of scrimmage.\n\nThe reason this team was able to make so many \"passes\", and do so on a kickoff return, is that they are passing the ball backwards. If a backward pass is not caught, it is a live ball and can be picked up by the other team to gain possession (as opposed to forward passes, which are dead balls if not caught.) \n\nThis makes them much riskier than forward passes, and that's why they're used only in desperate situations. Plus...you know...they move the ball backwards, which is not generally good for the offense.",
"The very high likelihood that the defense will get the ball coupled with the very low chance for additional gain. \n\nIt makes for a great highlight reel, but it's very rare to lateral the ball in American Football."
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f82ewo | if something has a 1% chance and i do it 100 times, will i get it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f82ewo/eli5_if_something_has_a_1_chance_and_i_do_it_100/ | {
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"Maybe. The total probability is 1 - .99^100 = .63 = 63% chance of succeeding at least once."
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2ua12u | why is occam's razor a thing? | I see it used a lot on Reddit. I've done some looking around but I must not be fully comprehending what it means and entails. What I'm getting is that "the simplest explanation is best". Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ua12u/eli5_why_is_occams_razor_a_thing/ | {
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"The principle is to try the simple explanation first. Because it requires least effort to verify or dispel. Occam's razor does not say the simplest is the correct. ",
"OP is so meta he doesn't even realize the supreme irony of this question.",
"It's not \"the simplest answer is best\". It's \"the simplest *sufficient* answer is the best. \"Do not multiply entities beyond necessity\" is the idea.\n\nIf it is necessary for the answer to be more complex in order to be complete, then that's fine. Just don't make it more complicate *than it needs to be*.",
"Occam's Razor is frequently misused. It's supposed to mean that given two equally valid explanations for something, the simpler explanation is better. If the simpler explanation is later found to be flawed, then it should be rejected in favor of the other. You never favor simplicity over truth.",
"Occam's razor says that the simplest answer is true all else being equal. It's just an informal rule. I think it comes down to there is no reason to posit the existence of something without proof. \n\nThe razor is just a rule to not make overly complex models for no reason. Take a model of the solar system with 8 planets and the sun. Yes there could be another planet that that we can't see and that's made of special stuff so that it doesn't effect the other objects gravitationally, without evidence one can safely disregard it's existence. The model with such an object is more complex than the one without. ",
"From wikipedia:\n\n\"The principle states that among competing hypotheses, the one with the ***fewest assumptions*** should be selected. Other, more complicated solutions **may** ultimately prove correct, but—**in the absence of certainty**—the ***fewer assumptions*** that are made, the better.\"\n\nWhat does that mean? It means that the more assumptions your theory requires, the weaker it is. A good example is believing that an old man in the sky is watching you masturbate and going to condemn you to an eternity in hell for touching your private parts. That's a bunch of assumptions that cannot be proved or disproved. Alternatively, you could believe that masturbation feels good and end your statement there.\"\n\nWhich one requires ***fewer assumptions***? The one with fewer assumptions is probably a more useful theory.\n\nI have formatted a few key words, because those words are important.\n\nTLDR: Occam's razor isn't about the simplest explanation, but about requiring the fewest assumptions in order to be true. The more assumptions you must make, the more likely you are fucking wrong.",
"one of the more famous examples, often used in medical stuff is \"if you hear hooves, don't think zebras.\"\n\nSo let's say you're in Kansas and suddenly you hear what appears to be a stampede of animals coming towards you. Now, being an inquisitive type of person you start wondering what kind of animal it is. \n\nNow, it could be a bunch of horses. You do know theres a horse farm in the area and the owner is kind of old and isn't keeping up on the fence. \n\n*or*\n\nmaybe it's zebras. But you're in Kansas and there aren't a lot of zebras around. But maybe there is a shipment of zebras getting sent from one zoo over on the east coast to another one over on the west coast. Of course, for travel time it's probably likely that they'd try and fly them if they had a plane that could, but maybe they couldn't get one so they put them on a train. but there isn't a train stop anywhere nearby, so that means the zebras would have been jumping off the train at full speed which is just crazy, so the train must have derailed. Of course that would probably have killed the zebras so the car in front of the zebras must have been carrying down pillows and they all spilled out ahead of the zebras and then the zebras got thrown into the pillows and now they're running away from the train wreck. \n\nOr, it's just horses from Old Man Johnson's horse farm. \n\nthe simple answer that explains everything is more likely to be right than the very complicated one. \n\nEDIT: Multiple people have told me that there is at least one good sized zebra farm in Kansas, though so far it seems the zebras haven't escaped so it's probably still horses. ",
"Do you think that conspiracy theories are generally an idiotic waste of time and energy? \n\nIf so, you implicitly believe in Occam's Razor. \n\nIt basically says don't make up shit just because you can. It's common sense. ",
"My understanding of it is that the simplest explanation is more *likely* - not necessarily best. It might not even be right, but if you're trying to figure out what's going on it's a good starting point.",
"Because UFOs.\n\nThat's probably the best way to frame it.\n\nIf you see a big ball of fire in the sky at around noon on a clear day, is it more likely that it's a UFO or more likely that it's the sun ?\nThat's why Occam's Razor is useful.\n\nAlso, it's not the idea that the simplest answer is the \"best\". It's a matter of going from most likely to least likely.\n\nThe problem we have (and have always had) is that people don't think like that. What they do is rate possibilities from most interesting to them to least interesting. So, as I said, because UFOs.",
" > Pluralitas non est ponenda sine neccesitate.\n\nIs actually what William of Ockham said. It's not really his idea, but one that he employed often. Roughly, it translates to \n\n > Don't propose another entity unless necessary\n\nOckham was talking ontologically - about things that exist. He was a scholastic monk, so he was very interested in analysing scripture, and was basically saying not to multiply different forms of existence beyond what was specifically mentioned or necessary to explain what was mentioned in the bible. \n\nSomewhat ironically, this principle has become a darling of the atheist/sceptic communities, and is generally applied ontologically with specific reference to a deity, but has also come to be used epistemologically (that is, with regards to knowledge or ideas). An argument that says 'you don't need God to explain the beginning of the universe' is ontological. An argument that says 'you shouldn't assume that there's a God because doing so biases your reasoning' is epistemological. In the latter sense, parsimony is applying to assumptions, so the principle can be rephrased as:\n\n > Don't assume too many things when you're trying to explain something. \n\nYou're right that in many cases it's used as 'a simple explanation is better than a complex one', and this is a methodological point. It has to do with how we *justify* a claim to knowledge. So this leads to the construal of occam's razor that might read\n\n > Don't choose a more complicated explanation over a simpler one. \n\nHopefully you can see that each of these rephrasings is making a distinct point, and each of these points are stronger in some cases than others. The ones which are closest to the ideals of the modern-day scientific method are the first and second, ontological and epistemological principles. The methodological one is more of a call to common-sense, which may or may not be the best approach to a given problem. ",
"It should be pointed out, that Occum's razor is not a trick for establishing a theory... it is a trick for finding a hypothesis to test.\n\nIt is suggesting that you start with the hypothesis with the fewest assumptions (simplest) and test it first, because more often than not, its correct.\n\nOthers have given great examples, but it is important to recognize that the razor has no place in the scientific method after the hypothesis is selected. \n\nOccum's razor is wholly useless on questions such as \"is there a god\", for example. where hypotheses exist but no method of testing does. You can't just declare (as BOTH sides do) that occum's razor supports one... it doesn't support either... it's used only to create, not prove, a hypothesis.",
"Other people have already explained what it is, but it's also important to realize that it is a rule-of-thumb used for the sake of practicality. A lot of people throw the term around while seeming to use it as proof that their argument is better. At best, it's only evidence that one argument is more practical than another, it's not proof of anything.",
"The answer that requires the least unreliable assumptions is most likely to be correct: as the required assumptions becomes more unreliable, the explanation becomes less likely to be possible and thus less likely to be correct.",
"The important thing about Occam's Razor is that it isn't really about that the simplest answer is best. The whole purpose of the Razor is to help you select the \"best\" hypothesis to test by choosing the one that requires you to make the fewest assumptions. Thus, the Razor isn't about declaring an answer the \"best\" answer because it is simple, rather it is about saying the best place to start testing is with the answer that requires the fewest assumptions. Occam's Razor is a starting point, not a solution.\n\nTo steal from wikipedia for my example, you can attempt to explain the motion of the bodies in the solar system with either a sun centered or Earth centered model (you can actually calculate everything and get the same values in both systems). However, you have to make a ton of assumptions about the sun centered version rather than the Earth centered version which requires \"7 assumptions.\" Of course that shouldn't be the end of it. You need to test or prove that the solar system is actually centered around the sun. Something being simper isn't evidence of veracity!\n\nThis is where you run into a lot of problems. People like to simply accept the simpler solution and quote Occam's Razor as their reasoning which doesn't really make sense. You also run into problems where Occam's Razor can be extremely different based on context. For example, I certainly wouldn't use it in any philosophical discussion because philosophy is very particular about word choice and so the meaning is different. Simpler is also a rather vague term in most cases that can be argued several ways. Is quantum mechanics complicated? You bet your ass it is. However, right now, it requires the fewest assumptions of things we can't prove so we test the theories of quantum mechanics to see if it actually holds true."
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3uv4fn | why is apple removing features from its new products? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3uv4fn/eli5_why_is_apple_removing_features_from_its_new/ | {
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"In general, Apple will add or remove features when they believe that the addition or removal will make them more money. This is either due to lower production costs, or higher sales and satisfaction. ",
"I assume you're asking about the headphone jack?\n\nThis is basically standard Apple behaviour. Apple has the reputation of having devices that “just work”. But that’s not magic, it’s not because Apple are better programmers than Microsoft or anything like that at all. Apple devices tend to “just work” because Apple maintains control over every element in the interaction.\n\nA large part of that is that Apple does not concern itself with how people want to use its devices. Apple decides how people are going to use the devices and if the customers would rather use another way they are simply out of luck. \n\nIn this case, Apple has decided to push everyone to wireless headphones or to headphones that have a lightning connector. The reasons here could be economic (Apple gets a royalty for every device with a lightning connector) or it could be technical (for whatever reason Apple wants a 2 way data connection with all headphones, perhaps for some future functionality). \n\nWe don’t know why apple made that choice. All we know is that from the next version of the iPhone onward, there will be no headphone jack. \n",
"I wouldn't care that much about removing a headphone jack since I normally prefer my Bluetooth headphones EXCEPT for when I'm on a plane and am not allowed to use the Bluetooth headphones.",
"Apple values user-friendliness or visual appeal more than function while making design choices. If removing a feature would make the product look better or be easier to use and less confusing for a new user, they will do it."
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2nybds | i turned my phone off with 65% battery. i just turned it on after an hour and a half and it's at 73%. what's happening? | Also, it's not depleting really fast, it's a real charge. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nybds/eli5_i_turned_my_phone_off_with_65_battery_i_just/ | {
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"A phone's battery percentage is an estimate of how much power it has left based on the power it is providing. Using an app that drains a lot of battery and checking the battery while it is still running will cause the ping reaction of checking battery to take a longer time to reach the sensor, resulting in a lower percentage. Usually phones make up for this, but occasionally cannot, so when you reset the battery (by turning off the phone) it will show a more accurate level."
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dl64kw | what is aws and what sort of work is involved? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dl64kw/eli5_what_is_aws_and_what_sort_of_work_is_involved/ | {
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"In the past, companies would have physical computers in specially cooled rooms that ran important functions such as serving websites, email servers or other specialised software. As the complexity of software increases and the way we consume content evolves, so does the amount of infrastructure required for these companies to work effectively. For many businesses and startups, managing this infrastructure is just something they generally don't want to do. Cloud providers such as AWS (Amazon Web Services), Google Cloud Platform (GCP) and Microsoft Azure (AZ) offer the same infrastructure, without the long term commitment and complications involved with running it yourself. So instead of managing physical servers and networks, replacing faulty components and so on... all of it is controlled over the net using the cloud providers infrastructure instead.\n\nUsually these cloud providers aim to simplify consuming common services, by wrapping up functionality in services that abstract away even more complexity. Examples include Amazon S3, which provides a way to store arbitrary bits of information and even serve it over the web globally, all without needing to really think about the disk it's stored on.",
"Alcohol withdrawal syndrome is a set of symptoms that can occur following a reduction in alcohol use after a period of excessive use. Symptoms typically include anxiety, shakiness, sweating, vomiting, fast heart rate, and a mild fever. More severe symptoms may include seizures, seeing or hearing things that others do not, and delirium tremens. Symptoms typically begin around six hours following the last drink, are worst at 24 to 72 hours, and improve by seven days.\n\nBenzodiazepines are effective for the management of symptoms as well as the prevention of seizures. Certain vitamins are also an important part of the management of alcohol withdrawal syndrome. In those with severe symptoms inpatient care is often required. In those with lesser symptoms treatment at home may be possible with daily visits with a health care provider."
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1pa1i2 | how can red, green and blue pixels produce billions of colors on my computer screen? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pa1i2/eli5_how_can_red_green_and_blue_pixels_produce/ | {
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"Because the red, green and blue subpixels have more states than just on and off. Each one can be lit at 256 different levels, so this produces 256\\*256\\*256 different combinations, which is about 16.8 million colours."
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4f3kpu | how does mvc programming work? | Hi! I just started using codeigniter and I love it! I have programmed in php for a long time, but simple things. Now I am tasked with a big project and CI will help... Only I can't seem to wrap my head around MVC programming. I know what code to write, but I usually don't know where to put it. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4f3kpu/eli5_how_does_mvc_programming_work/ | {
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"The M stands for model. This is where you create a data 'model' of the problem you are working on. You might have a user and that user has certain data related to it like a name and an address and a password. That user might have a 'shopping cart'. There might be many 'items' for sale. You want all of this code to reflect something about reality, but it isn't involved with how to interact with the user.\n\nThe V stands for view. This is how the data from the model gets presented to the user. There might be many different views for the same underlying data. All the view needs to know is that it will get model data somehow and then turn that into a data structure which will be delivered to the user. This might be a web page, a JSON object, calls to a graphics API, or something else completely.\n\nThe C stands for controller. It's involved with taking input from the user, interacting with the model to get some data, managing delivering that model data to a view, then handing the view back to the user.\n\nMVC is about separating concerns, in this case it separates persistent data (model), creating data for the user (data), and responding to user input (controller)."
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|
2o3rjy | why does rolling my shoulders seem to make a surge of warmth spread through my neck and back when i'm cold? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o3rjy/eli5_why_does_rolling_my_shoulders_seem_to_make_a/ | {
"a_id": [
"cmjheyd"
],
"score": [
2
],
"text": [
"I would assume it's because you're using the muscles in your neck and back to roll your shoulders."
]
} | []
| []
| [
[]
]
|
||
3vkwxe | how can eyelids block out so much light despite being so thin? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3vkwxe/eli5_how_can_eyelids_block_out_so_much_light/ | {
"a_id": [
"cxodfhw"
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"score": [
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"text": [
"Well, I'm going to answer with a question for you to think about: Why are you asking this about eyelids specifically? There are lots and lots and lots of things that you can't see through despite the fact that they're thin.\n\nIn fact, eyelids aren't even particularly *good* at blocking out \"so much light\". You can easily tell whether it's light out or dark out with your eyes closed, can't you?"
]
} | []
| []
| [
[]
]
|
||
9spr44 | can someone explain the basics of recombinant dna? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9spr44/eli5_can_someone_explain_the_basics_of/ | {
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"text": [
"Recombinant DNA is kind of like Frankenstein's monster, we stitched together a bunch of unrelated pieces into one functional thing.\n\nThe idea behind recombinant DNA is that it allows us to attach segments of DNA together that normally wouldn't be attached. \n\nSome examples of this are:\n\nAttaching an antibiotic resistance gene to another gene of interest, as a method of screening by bacteria death.\n\nAttaching a Lac-Operon to a gene so that we can test whether our gene is incorporated by generating bright blue bacteria clusters.\n\nNow, the important things: how does it work?\n\nDNA exists as two strands, paired together. There are 4 molecules of interest, labeled A,T, G, and C\n\nA is always paired with T, G is always paired with C.\n\nSo, what happens when there's a segment at the end of a DNA molecule, where one of the strands is longer than the other one (called an overhang)? \n\nWell, that just means that those lone molecules really want to pair up their partner molecules (see above).\n\nNow, this is the really important part. You can design two separate chunks of DNA so that they have complementary overhangs, so when you put them together, they will want to pair up. And when that happens, you suddenly have just connected the two pieces of DNA together.\n\nSo say, one chunk of DNA looks like\n\n\nAGTCGTCCCA\n\nTCAGCA\n\nso the CCCA exists as an overhang\n\nAnd the other DNA strand looks like\n\n\n---------ATGGTCTA\n\nGGGTTACCAGAT\n\nso the GGGT overhang exists. Now, the two overhangs will pair up, and you'll end up with a DNA strand that looks like\n\nAGTCGTCCCAATGGTCTA\n\nTCAGCAGGGTTACCAGAT\n\nnow, the full list of techniques to do all this is hard to describe, but one of the most important is the use of restriction enzymes, which are proteins, meant to cut at very specific sequences of DNA and make these types of overhangs. ",
"You find what section of DNA does something in another organism, say for example we get a few of our human cells and want to get a bacteria that produces human insulin.\n\nYou cut that section of DNA out from their genome using fancy chemicals called restriction enzymes.\n\nYou then take another bacteria and use the same restriction enzyme on its DNA. This cuts the DNA at a specific place.\n\nYou take those sections of DNA you cut out earlier and put them into the bacteria.\n\nThe DNA we got earlier connects with the DNA we cut.\n\nAnd now we get bacteria that make insulin.",
"Think of DNA like a computer program, and the synthesis process from DNA to proteins like an Operating System. Luckily for us, almost all eukaryotes on earth use the same 3 letters of DNA to form the same amino acids, which will link up to form the exact same proteins (for the same DNA sequence). Because of this, we can “load” the DNA for any protein into almost any organism.\n\nThere might be challenges getting the new organism to actually produce the protein, but this can usually be solved with promoters (instructions saying to make the next DNA sequence, instead of ignoring it).\n\n\nSome examples:\n\nYou can add the GFP gene in jellyfish to mice. The mice will produce GFP protein, which absorbs UV light and glows green. Since all the mice cells now produce GFP, the mice will glow green under UV alight.\n\nYou can add the gene for human insulin into bacteria. The bacteria will produce insulin, and after a few weeks the whole tank can be processed to extract human insulin for use in diabetes treatment.\n\nYou can add the genes for natural pesticides into plants. Some fungi produce toxins that kill insects trying to eat them, and these proteins can be inserted into plants, which will produce these anti-insect toxins, thus saving on chemical pesticides which may have surface runoff after rain and severe consequences downstream."
]
} | []
| []
| [
[],
[],
[]
]
|
||
de7hiq | value added tax in the uk | I thought its was just a 20% tax on all purchases, but after watching a YouTube video on it, it seems more convoluted than that | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/de7hiq/eli5_value_added_tax_in_the_uk/ | {
"a_id": [
"f2syen6"
],
"score": [
2
],
"text": [
"Conceptually a VAT adds a tax to each level in the production process in which value is added to a product. \n\nFor example, if you are making a widget then a company would buy the raw materials and then make the widget (step 1), and then another company would package it (step 2), and then anothet company would distribute it (step 3) and then another company would sell it (step 4). Each step along the way would be taxed (ie the distributor would pay a tax on their purchase from the packager, etc). This is in contrast to how it is typically done in America where all tax burden is placed on the point of sale. \n\nThe idea is the spread the tax burden across the entire process which decreases the tax burden on consumers and makes pricing more predictable and consistent."
]
} | []
| []
| [
[]
]
|
|
1wkqfq | how does pope francis differ in any substantive way from his recent predecessors? | There's a lot of rhetoric and he was on the cover of Time magazine and Rolling Stone. But how is he different? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1wkqfq/eli5_how_does_pope_francis_differ_in_any/ | {
"a_id": [
"cf2vs8h",
"cf2wdc4",
"cf2wgs8",
"cf2wpfg",
"cf301n7"
],
"score": [
6,
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2,
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3
],
"text": [
"Pope Francis has spoken out against the greed culture of capitalism. Since Francis regards himself as one of the poor (he lives a very humble life, without luxury), he has been much more outspoken than the last few popes about the greed culture of living and worshiping money. \n\nHe is always reminding us that there is much more to life than accumulating wealth and that capitalist exploitation is one of the seven deadly sins. ",
"I believe that the most important distinction is that Francis is reframing the message of the church.\n\nIn recent decades the political participation has been mostly related to \"social\" issues such as abortion, homosexuality, sex education, contraceptives.\n\nAlthough he made clear that doctrine in those respects hasn't changed, he is steering the church about other core beliefs of Catholics: charity and tolerance, most of all.\n\nFrom a political point of view, this is seen as a welcome change by most Catholics in a time where social norms are changing. Francis is reminding them that there are good reasons to apply Christian and Catholic values, and that it is not shameful to call yourself Catholic, just because the moral fabric of society is evolving from under their feet.",
"As a Catholic, not much really. Pope Francis is just a lot more charismatic than Pope Benedict, which makes him more popular with the media (plus he's in the honeymoon phase). Benedict also had the difficult job of following Pope John Paul II, who was arguably the most influential person of the later 20th century. The Papacy is not the presidency; he's not going to change everything his predecessor did because that's not his job. ",
"I'm a graduate student in a Catholic university, so there has been a lot of discussion about this around here. Most seem to agree the difference is in tone and style, but not in doctrine. For example his \"who am I to judge?\" comment about gay persons is often misread by many as a change in church doctrine about homosexuality. That is wrong. Pope Francis has not backed away from traditional church teachings about sex or gender. However he HAS sought to turn the attention of Catholic laypeople and clergy away from culture wars issues and toward the problem of poverty. In my opinion, this is such a substantial change in emphasis that from the perspective of a lay Catholic, it is not wrong to think of it as a substantial change, even if he is not releasing encyclicals that re-write doctrine. His focus on alleviating poverty might be said to represent a change in his own theology. In his younger days he has very critical of a strain of thought called Liberation Theology which is big in Latin America and has been (wrongly) equated with Marxism partly because of its emphasis on God's call to work to free the poor from structural injustice. However in his first few months as Pope he invited liberation theologians to the Vatican to meet with them. Read his first Apostolic Exhortation to get a sense of how he is ordering the list of moral priorities in the life of the church during his papacy: _URL_0_",
"As a lapsed Catholic, the biggest differences are in the rhetoric and the foci of his message.\n\nPrevious popes have focused a great deal of their energy speaking out against issues that do absolutely no good for the church's image, and will never gain traction with those (like myself) who are not devout. Issues like contraception, homosexuality, etc.\n\nPope Francis has immediately differentiated himself by saying that these are not issues worth discussing. He has said a number of times that all he wants to do is help his people love other people better, which he thinks will solve most all of the other problems (and I tend to agree in that sense). He spends a great deal of time interacting directly with the poor, often to the dismay of his handlers/staff in the vatican, and has shunned most all of the 'perks' that come with being the Pope. It's hard to know how much of it will cause changes within the church itself, but he's genuinely focused on leading the church by example, and he's setting a very humble and empowering example to follow."
]
} | []
| []
| [
[],
[],
[],
[
"http://www.vatican.va/holy_father/francesco/apost_exhortations/documents/papa-francesco_esortazione-ap_20131124_evangelii-gaudium_en.html"
],
[]
]
|
|
4t5xik | why do humans value beauty? | The articles I read says it's about us wanting better/healthier mates, yet we also value the beauty of a view, an artwork, or sometimes even a simple flower. Why is it, why do we like beautiful things? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4t5xik/eli5_why_do_humans_value_beauty/ | {
"a_id": [
"d5fax9o"
],
"score": [
2
],
"text": [
"Hey, could be TOTALY wrong here but, I don't think it has anything to do with mating or any of our previous natural instincts. When you see somethin Astheticly pleasing and unique (ie, mountain range, flowers, a face) You're taking in all you've learned up to this point in life and seeing it in some way. You see how a mountain scape took who knows how long to form and all the shit that must be going down across this huge space. You're seeing how complex the flowers must be and how even their smells are different for complex reasons. It's why kids aren't as easily impressed by nature, they don't really know yet."
]
} | []
| []
| [
[]
]
|
|
1k58ee | please explain some american politics to a canadian | Why does the USA only have two successful parties, and why do third parties have such a hard time breaking into the political game? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1k58ee/please_explain_some_american_politics_to_a/ | {
"a_id": [
"cblhuof",
"cblif1n"
],
"score": [
2,
3
],
"text": [
"Because at this point nobody is willing to \"waste\" their vote on a fringe party that will never get the votes to win. Everyone complains about the lack of viable choices but nobody will step up with their vote to give the other parties viability.\nAlso I think it can only be done using the metric system and we're not cool with that.",
"[CGP Grey explains](_URL_0_)"
]
} | []
| []
| [
[],
[
"http://www.youtube.com/watch?v=s7tWHJfhiyo"
]
]
|
|
5dy0gd | how and why does water drain clockwise south of the equator, counter clockwise north of the equator and straight down on the equator? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5dy0gd/eli5_how_and_why_does_water_drain_clockwise_south/ | {
"a_id": [
"da84sod",
"da854um"
],
"score": [
15,
4
],
"text": [
"Sorry to break it to you, but this doesn't actually occur. The direction the water goes down the plug is really just to do with how the water was already moving before the plug was removed. ",
"Generally, it doesn't. Or rather, [this effect can be demonstrated](_URL_0_), but you must be very careful to ensure that the water is very still before it begins to drain and that it drains evenly and slowly.\n\nThis is down to the Coriolis effect, which is a \"force\" observed on a moving body in a rotating frame of reference. The Earth is rotating, and as you move from south to north you're not really moving in a straight line - you're moving faster as you get nearer the equator. From Newton's first law that if a body is accelerating, there must be a net force on it, and this is called the Coriolis force. It means that a body moving perpendicular to the Earth's rotation will tend to follow a curved path (with respect to the Earth).\n\nThis means that water flowing toward a drain will tend to rotate a particular way, *but* this effect is very small. If the water is not perfectly still beforehand then the prexisting motion will have a much larger influence on the direction of rotation than the Coriolis effect."
]
} | []
| []
| [
[],
[
"https://www.youtube.com/watch?v=ihv4f7VMeJw"
]
]
|
||
7286qb | why does samsung release a less powerful version of it's phone in the usa then the rest of the world? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7286qb/eli5_why_does_samsung_release_a_less_powerful/ | {
"a_id": [
"dngm7ta",
"dngodwf",
"dngxfz2"
],
"score": [
10,
38,
2
],
"text": [
"Some provider in USA use CDMA.\n\nMaybe that's why they use Qualcomm chips or whatever it was. ",
"One of the American carriers (Verizon I think) use a specific cellular band CDMA which the more powerful exynos chips don't support. Samsung has to use Qualcomm chips instead for North American models which are less powerful but support the CDMA band",
"First, let’s clear something up. In direct comparison, the Snapdragon outperformed the Exynos in the S8: _URL_0_\n\nWhile it was true for previous generations, it is no longer the case that the Snapdragon is slower.\n\nThe primary reason for the difference is CDMA (specifically CDMA2000, IS-95 and EVDO Rev. A), which Sprint and Verizon use. CDMA was essentially developed by Qualcomm, and in order to use that technology it needs to be licensed from Qualcomm. This costs money, and it’s not very viable as very few countries use it.\n\nWhen 3G is finally left behind and LTE is the only mode of operation, these restrictions will no longer be necessary. While it is possible for GSM phones in theory on a CDMA carrier because it operates in LTE mode as well (assuming bands are correct and affiliation in CDMA isn’t required), it’s not common."
]
} | []
| []
| [
[],
[],
[
"https://www.anandtech.com/show/11540/samsung-galaxy-s8-exynos-versus-snapdragon/6"
]
]
|
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