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2fg3fz | "rogue cell towers". why is it difficult or not possible to find out who these towers belong to? | apologies if this has been asked or answered but i did not see the specific question being addressed . the recent circulating articles by slashdot and io9 regarding mysterious cell towers. how can something like this just be operating with no one knowing or claiming to know who they belong to or even their purpose? and would it be unlawful or possible to, in a non-damaging way, disable them until someone comes forward? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fg3fz/eli5_rogue_cell_towers_why_is_it_difficult_or_not/ | {
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"Yes it would be wrong for you to disable a communications tower because you don't know who operates it.\n\nHow do you know it's a cell tower and not a police/fire/ems band tower. In the USA they switched technologies about 8 years ago and now operate on a very similar band to cell.",
"Because they don't know the physical location of the \"tower\" beyond \"it's somewhere in this general area\". It's a nondescript box on a rooftop somewhere sending a signal that makes it look like a celltower access point to your phone."
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1xyz5w | the 50 new facebook genders - a brief description for each one - list inside.. i.e. the difference between trans male and trans man | Agender
Androgyne
Androgynes
Androgynous
Bigender
Cis
Cis Female
Cis Male
Cis Man
Cis Woman
Cisgender
Cisgender Female
Cisgender Male
Cisgender Man
Cisgender Woman
Female to Male
FTM
Gender Fluid
Gender Nonconforming
Gender Questioning
Gender Variant
Genderqueer
Intersex
Male to Female
MTF
Neither
Neutrois
Non-binary
Other
Pangender
Trans
Trans Female
Trans Male
Trans Man
Trans Person
Trans*Female
Trans*Male
Trans*Man
Trans*Person
Trans*Woman
Transexual
Transexual Female
Transexual Male
Transexual Man
Transexual Person
Transexual Woman
Transgender Female
Transgender Person
Transmasculine
Two-spirit | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xyz5w/eli5_the_50_new_facebook_genders_a_brief/ | {
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"Well, here's the beautiful thing about it. These aren't specifically tight. They can be loose. It all depends on what a particular person identifies as. \n\nOf course, this causes a problem in people who weren't born in a gender putting that gender as theirs instead of one of the many other options available which may describe them better... But this is Facebook, not a dating site. I think it's alright to do that.\n\n",
"Many of these mean the same or almost the same, so it's a matter of personal/cultural preference (what you feel more comfortable with).",
"I'll help where possible (source: I am a trans woman)\n\nAgender, any form of androgynous, 'neither', and 'neutrois' are essentially the same - the person does not actually identify with a gender, period. Not male not female.\n\nAny form of 'man/male' or 'woman/female' are the same - the title of male or man is the same. The titles of 'trans male' and 'trans man' are the same.\n\nAnything prefixed with 'cis' refers to someone who identifies as the gender they were born (the vast majority of people). Typically, if you have to ask 'how can you possibly not feel like the gender you were born' you are cis gender. :)\n\nThe terms bi-gender, two-spirit, gender queer, gender fluid - typical refer to someone who identifies as 'both' male and female. They all typically refer to someone who may identify differently on different days - with the exception of gender fluid who may change throughout the day.\n\nTrans male or trans man refer to someone born genetically with the female sex but identify as male. They are interchangeable.\n\nTrans female or trans woman refer to someone born genetically with the male sex but identify as female. They are interchangeable.\n\nThe term 'transsexual' in any context is typically not used anymore, but can sometimes be used to identify those who have fully completed the surgeries to completely change their sex.\n\nNon-binary is a fairly blanket term that means they fall somewhere on the spectrum that does not match societal norms. It is a pretty all inclusive term, but may also refer to someone who identifies as 'mostly' one or the other gender, but not entirely. \n\nIntersex is a term specifically for those born with both sets of reproductive organs. They are truly biologically both male and female.\n\nHope this helps :)\n",
"First off, this is a question easily answerable by google. But since I don't want anyone to be misguided by anything, I'll answer it here. \n\nI'll just go in order.\nAn agender person is someone who doesn't identify with any gender, be it male, female, or otherwise. \n\nAndrogynous people are those who don't particularly identify with either make or female, but rather exhibit characteristics of both. \n\nBigender people are those who identify with two genders all the time. This could mean male/female, or androgynous/agender. Bigenderism ksnt limited to the binary genders (male/female.)\n\nCis (short for cisgender) means that someone identifies with the gender they were given at birth. Most people in the world are cis. \n\nFemale to male (FTM) people were assigned female at birth but are actually male. \n\nGenderfluid (that's me! :D) people's genders can change from time to time. For example, I usually go from neutrois and androgyny. \n\nNeutrois is a neutral gender identity. \n\nGenderqueer and gender nonconformity are just labels someone has when they don't particularly identify with anything else. \n\nMTF is someone who was assigned male at birth but is actually a female. An MTF person could also be called a trans woman or trans female. \n\nNonbinary is an umbrella term for anyone who doesn't identify as fully make or fully female. \n\nAlso, someone before me commented that cis is a slur. It's not, it's just another label for anyone who's not trans! If you want more info feel free to ask. ",
"Why are there so many labels for these things, no disrespect intended, but do we really need this many labels? ",
"Completely serious: What is it about having a label (particularly the correct label) that helps you, if that's your thing?\n\nI honestly just don't care as long as whoever I'm talking to sees me as a collection of all MY traits and not traits or values that are generalized from just my gender or sexual identity. I'd sincerely like to understand why having those correct identifiers matter so much to some.",
"[this was a link posted on r/lgbt a little bit ago](_URL_0_)\n\nA lot of these are different variations of each other because everyone prefers different things, so some definitions are basically repeats. The reason why they have repeats of some is so everyone can find something they fully identify with, so they don't have to compromise with something else. Some people think it's dumb but it helps the small percentage of people who really need it.",
"Pardon my ignorance, but when was the 'QI' added? And wasn't queer a slur for the LGBT community?",
"For all the people here wondering aloud, \"why is it so different now?\" or \"why do people need to have a 'label?'\" \n\nThe gender spectrum hasn't quite changed, throughout all of history, there have been people who have felt different than the gender assigned to them according to their genitals. In some civilizations, it was okay to say this out loud, but in many you'd be dubbed dangerous, crazy, or worse, and one may be ostracized or worse. The difference now, is that (slowly) the gender spectrum is becoming more respected, and gender queer/trans communities are supporting each other and not remaining silent anymore. Getting a job or a house, not being bullied/harassed in school/work/public, or not being shunned from resources and institutions, are all reasons why being public about these labels matter. Without being loud about them, and clarifying to everyone, the rest of society will remain confused at best, hateful at worst. The labels are a struggle for self-determination, for the right to exist, to be respected like cis people, and so much more.\n\n\n",
"Can someone provide a definition for all of these? I really just don't understand ",
"A note to people posting here: ELI5 is not for debates. If you want to argue about the validity of people's chosen gender identity, do it somewhere else. ELI5 is for the dissemination of objective information, not debate.\n\nI will be handing out bans to anyone who engages in an argument about gender identity, and I don't care what side of the issue you're on or whether you're right or wrong.",
"To what extent do these apply to identity only, and not also physical appearance?",
"Why is there a transmasculine and not a transfeminine?",
"Something I've noticed and maybe someone here can correct/expand upon. It seems like all the terms for gender identity are somewhat chosen or preferred by the people who identify with that particular term. I've understood that to be because it's respectful to refer to someone in the way that they are most comfortable. The exception seems to be the\"cis\" terms. It kind of seems like an odd term to me and I just wondered if there were other options. ",
"Just for the sake of clarification everyone - and if we can't agree to this point, then most debates about this subject will hit a brick wall...\n\nGender and Sex are not mutually tied, and can exist independent of each other. \n\nThe organs you are born with may OR may not be locked up with the gender that the world around us assign to those organs. This is helpful to understand when we talk about socialization vs. biology. ",
"Dude I'm trans and I don't even know the difference between a trans male and trans man. "
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65065f | is it legal to domesticate any critter as household pets? | I.e. raccoons | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/65065f/eli5_is_it_legal_to_domesticate_any_critter_as/ | {
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"It depends on, among other things, where you live. Even within the same country, rules can differ from region to region. For example, in New Mexico, it's legal to keep a domesticated skunk if you have a certain permit and follow certain rules. However, if you go to Minnesota, they are not legal as pets no matter what sort of permit or documentation you have.",
"No.\n\nMost jurisdictions have specific laws about keeping wild animals and exotic pets. The particular status of Procyon Lotor no doubt depends on location.\n\nNote, you keeping one as a pet ≠ domestication. To domesticate something you're going to need to raise several hundred generations in captivity. ",
"Not a full answer, but I know that certain animals that are deemed by the local government to be pests, such as wild boars in Texas, can be shot on sight, regardless of whether they are domesticated or not. I remember also seeing a video where an invasive species of deer was domesticated by a family and the police shot it right on their lawn and as far as I know they were not punished for doing so.\nThis doesn't fully answer your question, but certain animals certainly don't have the same rights as others, it all depends on what your state/province allows.",
"That depends on where you live. I'm pretty sure the US has laws prohibiting you from keeping any endangered or threatened species as a household pet. States probably have their own laws on what counts as a pet as well and almost all mid-sized or larger cities have ordinances defining what pets can be kept within the city limits. Some even go so far as to limit the number of cats and dogs you can have.\n\nMost of the time ordinances prohibit \"exotic animals\" or \"wild animals.\" For example, here's the ordinance for Houston, Texas:\n\n > As used in this article, the term 'wild animal' shall mean any mammal, amphibian, reptile or fowl of a species that is wild by nature and that, because of its size, vicious nature or other characteristics, is dangerous to human beings. Wild animals shall include, but not be limited to, lions, tigers, leopards, panthers, wild cat-domestic cat hybrids up to the third generation, bears, wolves, wolf-dog hybrids, cougars, coyotes, coyote-dog hybrids, raccoons, skunks (whether deodorized or not), apes, gorillas, monkeys of a species whose average adult weight is 20 pounds or more, foxes, elephants, rhinoceroses, alligators, crocodiles, caymans, fowl larger than a macaw, all forms of venomous reptiles and any snake that will grow to a length greater than eight feet. The term shall also include any animal listed as an 'endangered species' under the Federal Endangered Species Act of 1973, as amended, or any fowl protected by the Federal Migratory Bird Treaty Act. The term wild animal shall not include gerbils, hamsters, guinea pigs, mice and domesticated rabbits.\n\n > It is unlawful for any person to be in possession of a wild animal.\n\nYou can read the whole thing [here](_URL_0_)."
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3hrlmk | if teachers have to spend so much money out of pocket on school supplies for class why don't they just stop? | Little Timmy forgot his pen and notebook today? Tough shit Timmy. Make some friends and ask them | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hrlmk/eli5if_teachers_have_to_spend_so_much_money_out/ | {
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"Teachers are kind of strange in that they care about the children under their charge and also care about their jobs. Kind of crazy I know",
"Little timmy gets restless and disruptive, and distracts all the attention from the other students, now the whole lesson plan is ruined. Also, teachers want to teach, they want kids to learn and progress, that's what gives them professional and personal satisfaction and joy (source, I am a teacher). Ignoring a students for an entire day because he forgot a pencil and a piece of paper, which would cost 10c, seems kind of petty and unprofessional. \n\nNot to mention that job security and pay raises are tied to student performance on standardized tests, so its in teachers best interest that every student does well.",
"Teachers are evaluated in part by how well their students learn. Spending an extra $100 a year on supplies very well could get them more in the long run.\n\nYou also have the hassle factor. Yes, little Timmy could just sit and suffer, but how much extra work will that make for the teacher down the road? ",
"Former high school teacher here. Two thoughts come to mind. \n\n1) Nobody gets into teaching for the money. If you're a teacher, you probably have some sense that people deserve equitable access to education and educational resources. It's difficult to ask someone whose job requires deep empathy to ignore problems that have clear solutions. Do I want to pay for classroom supplies? No. But they are necessary and a reliable alternative hasn't presented itself. I'll pay for them, report the cost on my taxes*, and do my best to ensure those kids aren't being cheated. \n\n2) You're probably thinking too small here. The cost of pencils or paper isn't breaking teachers; it's technology. I know a lot of teachers that have to pay for their own computers, printers, projectors, document cameras and scanners because reliable ones aren't made available to them through the school or district**. Pairing technology with interactive teaching strategies can reduce the [achievement gap](_URL_0_) and drastically improve classroom management, but so few low-income schools have access to those materials. \n\nWe know how to fix the problem of education in America. We're just not willing to spend the money. \n\n*Teachers are capped on tax returns for teaching supplies. I recoup less than a fifth of what I spend in a year. \n\n**If they're made available, many of them have usage caps that prevent them from being functional for your given class sizes (EX: I'm capped at X number of copies with Y number of students, Y > X). ",
"Teachers for the most parts are saints. Dealing with punk ass kids for this little pay? God bless them"
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rqd41 | what helps and hurts my credit score? | First- is it a rating of how likely I am to repay my debts, or does it rate how profitable I am as a debtor?
For example, I understand that making payments on time helps one's credit score, but what if those payments consistently eliminate remaining balance without racking up any interest?
I understand that the exact formula for one's score is a "trade secret" and is probably different among the three companies, but what helps and what hurts? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/rqd41/eli5_what_helps_and_hurts_my_credit_score/ | {
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"I recently got a job in the financial industry that requires me to pull credit on people all day long. I don't know too much about what builds a credit score yet, but what hurts it is mostly the stuff you'd expect. Not paying credit card bills on time, charge-offs (which I think is paying a credit card with another credit card, or something like that), bankruptcies, foreclosures, etc. But the thing you wouldn't think about- having your credit pulled (an \"inquiry\") actually lowers your credit score each time it's done. ",
"What helps your credit score is a history of paying bills on time. Having a long history of paying bills, and a large diversity of bills, is what helps the most.\n\nThe credit score is not affected by how profitable you are as a debtor. Someone who constantly charges large amounts to their credit card and pays it off slowly wouldn't have a higher credit score than someone who doesn't. In fact, keeping a low balance on your credit card helps your credit score. [Source](_URL_0_)\n\nHowever, if you never borrow any significant amount of money it may take longer to establish a very high credit score. It isn't necessarily a bad idea to take out loans: for example, student loans usually have very low interest rates. If you buy a car, even a used car, you can often get a lower interest rate by putting more money down - for example pay for 30% or 40% as a down payment and finance the rest at 1% interest. Choosing to take out a loan even though you can afford to buy a car with cash can help your credit score when you're young.\n\nPaying your electric bill and cable bill counts, too! Any regular payment you make on time helps establish your credit score.\n",
"ive often considered obtaining the credit company algorithm to be a worthy cause for hacker. that whole \"were going to use it against you and you cant know how\" - thats as arrogant as when a woman says \"if he doesn't know why im mad, i certainly am not telling him\"",
"There's a good (if lengthy) guide to credit score on MonetSavingExpert: _URL_0_\n\nIt's a UK-based site so may not all apply if you're in the US or elsewhere, but it gives you an idea."
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4xbp2k | how does gymnastics stunt growth? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4xbp2k/eli5_how_does_gymnastics_stunt_growth/ | {
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"Overtraining can cause low estrogen levels which can lead to not having a menstrual cycle. ",
"Two days ago I believed women had puberty delayed by competitive gymnastics. Then I researched it and found now people are considering whether professional gymnasts may be smaller just because it's an advantage that pushes bigger gymnasts out of the running for the top prizes.",
"The intense exercise and training schedule, along with a meticulous diet puts a severe stress on the body not unlike adult female competitive athletes who often perform great but whose blood work shows abysmal progesterone and estrogen levels coinciding with a loss of menstrual periods.\nThey put their body through so much physiological stress that it shuts down their ability to grow. The body's resources are diverted to trying to survive the stress.",
"They are not really sure if it stunts growth, or if those with stunted growth tend to be attracted to it and excel at it. \n\nWhat they do know is that being smaller and less \"developed\" physically is an advantage for most of the gymnastic events. So that alone makes successful gymnasts inclined to be smaller. You also have the fact that with women, extreme athletic training and exercise such as what olympic athletes do and that changes their hormone levels and often will lessen or even prevent menstrual cycles. ",
"The simplest reason is that any sport where people must maintain a low weight will delay puberty, which in turn can result in being smaller at the end of puberty.\nIn things like ballet this is common, with some girls not hitting puberty till their late teens due to their lower body weight."
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yytq9 | why do microsoft and other software companies care which internet browser people use if the software is free? | After reading that in Windows 8 non-IE browsers will be intentionally slowed down, it made me think - why does anyone care what software we are using if we use it for free anyway? I am sure I am missing something. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/yytq9/why_do_microsoft_and_other_software_companies/ | {
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"There are several important reasons, but it mostly comes down to peoples browser having a potentially large impact on what they do online, which *does* have money involved. In particular, it affects what money-making online applications they might use, such as the search engine, with IE defaulting to Microsoft's Bing and google being popular elsewhere. Since many people never change their browser's default settings, that's a lot of indirect money tied up in browser choice.\n\nThere are also deeper reasons along the same vein. For instance, google's Chrome originally had a superb javascript engine, which its competitors have now raced to catch up with. This all benefits google, as their business is tied up with complex web applications, but these applications need fast, optimised browsers to be usable.",
"1. Create a browser\n2. Optimize it work work better with your web products\n3. Sell web products to web developers\n4. Profit\n\nMicrosoft's strategies have often been described as \"Embrace, Extend, Exterminate\". They take an open standard, add closed, proprietary stuff to it, get everyone to use the closed stuff, then drive their competitors out of the market.\n\nSo if they can control the browser, and make it work very well with .NET and Silverlight, and not so well with Javascript and Flash, they can create a bigger market for those tools.",
"If people get used to browsers that work in other operating systems, especially considering how much things we do online now, that will be tough for Microsoft that lives on selling Windows and MS Office (compatible with Windows and Mac only).",
"Warning: I didn't sleep a wink last night and it's currently 5:30 AM. Also, this is largely my personal opinion.\n\nIt's about choice and what could (and previously *has*) happened when it's taken away from you.\n\nFirst of all, I imagine some people are worried about a repeat of IE6. See, what happened was that Microsoft abused their position in the operating system market to force their only major browser competitor (Netscape) out of business. Once they'd done that, they let IE stagnate for years since they didn't need to compete with anyone.\n\nHowever, Mozilla (which rose out of the ashes of Netscape, kinda) made Firefox and spurred competition again. With Windows 8 RT, Microsoft is ensuring that *this cannot happen*. They are basically setting themselves up to be immune to competition.\n\nWhat's more scary that it isn't just browsers, it's *everything*. As a user, you may only install programs that Microsoft allows you to. If you want to write software for Windows 8 RT, you have to use the Microsoft runtime, ask Microsoft for permission, pay them a cut of your profits and abide by their rules as to what your programs can and cannot do. Even worse, you can't even compete with Microsoft's own programs since they get access to *what used to be normal features* of the OS and you don't.\n\nBut it gets worse. Microsoft is also requiring companies making Windows 8 RT devices to ensure that *only* Windows 8 RT will run on them.\nThis is **absolutely terrifying** to anyone who cares about free access to computers. Apple locking down smartphones is bad enough, but locking down a desktop OS is nightmare stuff.\n\nSo I would say that Microsoft blocking browsers is less about them blocking browsers and more about a concerted push with Windows 8 RT to block all possibility of competition.",
"Think of the Internet as a big city with lots of places you can go visit by travelling along the roads. Think of a browser as a bus which normally follows a fixed route. If you choose one bus instead of another then you will be taken right past certain shops where you might end up spending money while other shops are not on the route. \n \nPeople who understand the Internet very well are able to drive the bus themselves and go where ever they want so this doesn't matter so much to them but most folks just go where the bus takes them. \n \nSo, the people who own the shops pay the bus driver to drive past their places of business or sometimes the shop owner also owns the bus. Either way there is money to be made by bringing people places where they might spend money.",
"Microsoft really didn't have to give a shit until they got into bing and advertising. But they did anyway, it was clear the internet was becoming an incredibly big deal and they wanted to capitalize on it in every way possible. \n\nMicrosoft's approach to this was to try and define the standards of the internet, they accomplished this by releasing several shitty browsers that were not standards compliant. They all had proprietary implementations of html, javascript and css. with a lot of \"microsofty\" ways of doing things. \n\nThe hope was that since every windows pc came with their browser their implementation of the technology would monopolise the industry.\n\nthey failed incredibly hard."
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7ago01 | how are proteins important in the nervous system? | Yeah, so I looked this up and it gave me some biochem gibberish or something. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7ago01/eli5_how_are_proteins_important_in_the_nervous/ | {
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"Proteins are important in the nervous system for the same reasons they are important in any cell: They provide structure, act as catalysts for metabolic reactions, work in cell signaling and transport of substances within, into and out of the cell.",
"Also, proteins are made of of amino acids. Amino acids can be neurotransmitters, or can be assembled into neurotransmitters. For example. Without these amino acids, your nervous system would not work. "
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2fhy89 | why the dallas cowboys are touted as "america's team" and not the new england patriots? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fhy89/eli5why_the_dallas_cowboys_are_touted_as_americas/ | {
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"because of their cheerleaders, honey.",
" > The term \"America's Team\" is a popular nickname in the United States that refers to the Dallas Cowboys. The nickname originated with the team's 1978 highlight film, where the narrator opens with the following introduction: They appear on television so often that their faces are as familiar to the public as presidents and movie stars. They are the Dallas Cowboys, \"America's Team\".[1]\n\n_URL_0_\n\nTV Deal in the early 60's led to them building a fan base in cities that did not have a team.",
"Because Texas likes to make itself seem more important then it really is."
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f5jtmt | how does sarcasm work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f5jtmt/eli5_how_does_sarcasm_work/ | {
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"Oh reallyyyyy?!?! You never understood it.",
"Are you perhaps not a native English speaker or on the autism spectrum?\nSarcasm is when something is said, often in an exaggerated tone, to imply exactly the opposite.\nFrom _URL_0_:\n\nTypes of Sarcasm\n\nSarcasm often depends upon the voice tone. There are seven types:\n\nSelf-Deprecating Sarcasm – This category of sarcasm expresses an overstated sense of inferiority and worthlessness.\n\nBrooding Sarcasm – In this criticism, the speaker utters something polite. However, the tone of his speech has a marked bitterness to it.\n\nDeadpan Sarcasm – It is expressed without emotion or laughter, making it difficult for the listener to judge whether the speaker is joking or mocking.\n\nPolite Sarcasm – A speaker is said to have delivered a polite sarcasm when his listeners only get to realize that his kind remark was a sarcastic one after they had given it some thought.\n\nObnoxious Sarcasm – This kind of sarcasm makes people feel like punching the speaker in the face. It is not very funny, and it gets under your skin.\n\nManic Sarcasm – This type of sarcasm is delivered in an unnatural happy mood, which makes the speaker look like he has gone crazy.\n\nRaging Sarcasm – This kind of sarcasm relies mainly on exaggeration and violent threats."
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9swyab | although adults constantly tell me all cucumbers are 95% water, why does water taste bitter if i drink it after i had a cucumber? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9swyab/eli5_although_adults_constantly_tell_me_all/ | {
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"Because the other stuff in a cucumber gives it flavor. A soda is going to be > 95% water. Tea and coffee are > 95% water. If I get sick and take a shit, it might even be > 95% water. Doesn't mean it's going to taste like plain water.",
"Your sense of taste is not based on percentages.\n\nSeawater has a salinity of only 3.5%. But it has an extremely unpleasant taste.\n\nYour sense of taste developed to detect what is palatable and what is not. To determined what is food and what is not.",
"Cucumber (like all plants) has naturally occurring sugars, while not nearly as much as something like an orange it's still enough that you get used to that as the norm then when you drink water that doesn't have those sugars it tastes that as bitter because it is expecting the sugar from the cucumber.\n\nAs similar but more exaggerated example is drinking orange juice after brushing your teeth "
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26i0oo | why do mosquitoes bite the shit out of me but not other people? and why do they only come out at sunrise/sunset? | i hate em | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/26i0oo/eli5why_do_mosquitoes_bite_the_shit_out_of_me_but/ | {
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"Mosquitos actually favor certain blood types over others.\nYour scent has something to do with it too.\n\nBananas are known to increase your yummyness as well.\nLocation too. If you pass by grass that has dormant mosquitos, they're more likely to be like 'noms are here.'",
"Mosquitos are also quite attracted to sodium. \n\nDo you consume a lot of salt in your diet? There's a possibility that the sodium is being excreted through the pores of your skin via sweat."
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5lvjgk | what makes snapchat a successful messaging platform over competitors? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5lvjgk/eli5_what_makes_snapchat_a_successful_messaging/ | {
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"The image / message you send is only available for 10 seconds. Then it gets erased and lost forever.\n\nNot really forever. But you get a warning if they take a screenshot.\n\nThe thing I like the most about Snapchat is that you can't edit the photos you take. You just take it and send it, no edition like Instagram p.e."
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9fxhk8 | how to hear the beat in music. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9fxhk8/eli5_how_to_hear_the_beat_in_music/ | {
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"The first line \"fortunately you have got someone who relies on you.\" That's 4 measures (bars.) In this song, that's 16 beats. If you listen to the percussion in the intro, prior to the lyrics beginning, you'll notice it's a pattern with very slight variations. If you can count 1- & -2- & -3- & -4- & , repeated 4 times in that line of lyrics, you'll find the beat. The \" & s represent the \"up beat\" and the numerals the \"down beat.\" Together, (in this and many songs) they are one beat. Any time you're listening for the beat, you should start with percussion, and go next to bass."
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2jxh5t | which file formats respond best to compression, and why? | Sometimes, archives of one type of data get compressed much smaller than archives of another type. Which file formats are compressible, and which are already compressed to the max? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2jxh5t/eli5_which_file_formats_respond_best_to/ | {
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"Random data with no pattern makes the worst form of compression, anything with repeating pattern(s) makes the best. \n\nEdit: I'm also adding in that some compression is lossless and some isn't. A lossless compression is required for something like a text file; when uncompressed, you want your text to still be the same.\n\nOn the other hand, something that utilizes lossless compression -- such as mp3 -- actually shrinks it down by discarding data that the compression thinks is unneeded. Typically, with lossless compression, you can specify how much loss you want at the cost of the quality. Thus, the more loss you are willing to tolerate, the higher the compression. "
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9smkix | how does dust get in closed places like closets and drawers that are rarely opened? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9smkix/eli5_how_does_dust_get_in_closed_places_like/ | {
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"Since dust is everywhere in the air it comes inside these closed places simply by opening them. \nIf you analyze a m^2 of air you can find millions of particles. While going through the air you barely notice them. But if the drawer if being opened the air inside the drawer partly replaces with the much more particle filled air. \nIf you now close the drawer these particles can settle down because the air is not moved anymore. This layer of particles will become so thic that you can see them. \nAlso, these closed places are never really sealed. Since these particles are very tiny, they get into sealed places simply through holes. ",
"There are two main ways. Firstly there are cracks in the doors and panels which does allow air through which will bring some dust as well. Once inside there is less airflow so the dust tend to settle. Secondly most materials will give off dust by itself over time as it crumbles. If you were to study the dust in a drawer which have been closed for some time you will notice that most of the dust is tiny sawdust from the walls and ceiling of the drawer."
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5olnu7 | how does a sound stimulate the brain? | Recently, I have started to listen to brown noise while studying to boost my productivity. While listening to it, I could focus and concentrate on studying without being distracted. Being the person easily distracted, this surprised me a lot, so I was just wondering, what is the science behind this?
_URL_0_
Here is the LPT! | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5olnu7/eli5_how_does_a_sound_stimulate_the_brain/ | {
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"Brown noise or white noise helps you focus because the brain processes it as silence. In a quiet room and even in complete silence, slight noises like the beating of your heart or blood flow through your ear are still present. Brown noise covers these sounds up and replaces it with a more complete\"silence.\"",
"\"Your brain is especially attuned to detect changes in your surroundings. If there's a low level of background information...when it's silent almost any sound can alert your brain and you can't help but to pay attention...like a dripping tap or a snoring partner...white, pink and BROWN noise playing across all frequencies are like a muffling blanket of sound....they mask other sounds by making them less significant when compared to the background\" \n\n...I didn't explain it like you are five, [its from this SciShow] (_URL_0_)\n\nEssentially brown noise isn't distracting, its a nice blend of sounds balanced for the human ear so that the highs aren't too high. This helps minimize outside interference allowing you more brain power to focus on the task at hand rather than wasting it interpreting random noises, a trait which may at some point in human evolution permitted you to survive and extended your gene pool's fitness but now, in the age of information, prevents you from studying. \n\n\nEDIT: I attempted to provide my own summary of the video",
"Brown noise helps you focus by removing auditory distractions. Its the same idea as closing your eyes to help you hear or smell better.\n\n\n\n\nBrown noise works better than simply blocking out sound with earplugs because our hearing become more sensitive when it's quiet. In a completely silent room where you can \"hear a pin drop\", the faintest of sounds (e.g. the aforementioned pin) will stick out. Your brain needs to assess all of these faint sounds to ensure they aren't important (a threat, your name being called, etc.). If you are listening to brown noise, you can't hear anything other than the brown noise, so there are no other sounds for your brain to assess. Furthermore, your brain determined the brown noise was unimportant and could be ignored within a few seconds of turning it on, so with no new sounds to interpret, you've done the auditory equivalent of closing your eyes.\n\n\n\n\n\nIf you're looking for a bit more science, we can talk about brain regions. Although there are specialized areas for different types of sensory processing (occipital lobe for visual stimuli, the primary auditory cortex in the temporal lobe for auditory stimuli), this information still travels to the frontal cortex to be consciously assessed. Brown noise allows the primary auditory cortex to stop bugging your frontal cortex with dumb messages like \"HEY! A DOOR JUST OPENED! DO WE CARE?\" and lets it focus on important things, like the exam I should be studying for right now.\n\n\n\n\n\n\n\n**TL;DR listening to brown noise is the auditory equivalent of closing your eyes to focus**",
"I've always heard it called \"white noise\". Is there a difference?\nNever moind.\n_URL_0_\n",
"What you are looking for is most likely the phenomenon of [stochastic resonance](_URL_0_).\nSimply explained, it works like this:\n\nTo successfully send and receive a signal, your nerves/neurons need to get their electrical signal over a certain threshold so that it counts. \n\nIf you add random but constant noise to the situation, it adds to the strengths of all signals, making them more likely to cross the threshold and being effective. \n\nThe German wiki-article has a good picture too explain it: _URL_1_\n\nSo now more of the signals have effect, which is similar to having better concentration/\"stronger brain signals\".\n\nThe isolation from distractions is also very useful, but complete silence without distractions would have less of an effect than white noise.\n\nA related example would be one of the main factors of ADHD:\nDue to a lower dopamine level, control-signals in the frontal lobe are less likely to have an effect and an ADHD brain needs more effort to reach the same level of concentration/control. If you correct the dopamine level through certain drugs (which would put other people in TOO-MUCH-DOPAMINE-EVERYTHING-IS-INTERESTING-MODE aka \"being stimmed\"), concentration returns to normal level."
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66b078 | why is apple just sitting on the largest capital in the world? why not use it to invest, innovate, acquire etc.? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66b078/eli5_why_is_apple_just_sitting_on_the_largest/ | {
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"They are! But the thing is - they also have to try and make a profit off that.\n\nThat's Apple's big problem. They have SO MUCH cash flow, that even after buying all the things they want and funding all the R & D they want, and paying their shareholders they STILL have more cash. \n\nWhat a great problem to have.",
"Supposedly they are going to be getting into virtual reality soon. I'm excited to see what they bring to the table. They need more things to invest in",
"Taxes.\n\nApple makes a lot of money abroad, and through shifty tax minimization (mainly in Ireland, but a little bit in the Netherlands too) pay almost no tax on those earnings. If they wanted to repatriate that money to the US to put it to work they'd have to pay taxes on it.\n\nThey don't want to pay those taxes, so the money just sits.",
"Im a finance student in my undergrad so im going to try to answer this to the best of my ability.\n\nApple is extremely succesful as a public company and while yes they do have some sketchy tax 'evading', they cite a different reason for such large capital:\n\nApple wants to hold onto massive amounts of capital in order to be the bleeding edge in electronics technology. Most public corporations return money to shareholders in an attempt to keep shareholders happy. This may be through buybacks or dividends or what have you.\n\nA couple years ago shareholders actually tried to get Apple to cough up some cash to investors, and some did eventually get returned.\n\nBut all in all Tim Cook believes the way to be first and best is to sit on huge resources, keeping technology pushed before keeping investors 'happy'.\n\nTL;DR\nApple keeps money to be able to quickly attack new technologies, ignoring investors wishes.\n\nHope that helps.",
"It's in the personality of Tim Cook. He is great at making things more efficient, optimising logistics, and other such things. He's also a rather careful person who wouldn't throw tons of money after ideas he isn't certain to be successful.\n\nAdditionally, the money is probably not just lying around, but creating interest. More than Apple would probably get from most possible projects. And the interest comes from stocks or bank credits, where others do business with the money, so except for Apple, nothing goes to waste.\n\nOther personalities might have lowered prices to drive market share. Again others would put all the money into some good and some bad projects - so that Apple goes through more lows in terms of profitability, but also innovates more. Cook is neither power hungry nor fanatical enough for such.\n\nI personally think that Apple should acquire more companies to broaden its abilities. It should be a little more willing to pay for patents that are worth having in their products. Its software development, which imo is at the core of its success (it was the ease of use of Macintosh, iPod, iPhone, and so on which made them so popular), should expand drastically so it can keep up with Google and others on artificial intelligence and other things, and so on, and so forth.\n\nI also believe it should keep a few more businesses which don't make much money but help stay competitive technologically - large powerful laptops, servers, more ambitious Macs, and so on.\n\nIf it did all that, it could easily ring in another revolution like that of the Macintosh or iPhone again. And again.\n\nWhich I, if anyone was stupid enough to let me be CEO, would definitely prefer over maximum profits."
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1j1wca | why some people sleep walk/talk and other don't | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1j1wca/eli5_why_some_people_sleep_walktalk_and_other_dont/ | {
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"Hi there.\n\nThis is called Somnambulism. It occurs at any age, can be genetically linked and effects 4% of adults.\n\nSleep walking/talking occurs during phase 4 of the sleep cycle. Night terrors (not to be confused with nightmares, which occur during REM) also occur in phase 4. Children are the most susceptible to experiencing this kind of activity, as they have not grown out of the predisposing factor of experiencing a lot more of slow-wave sleep (a deep non-REM sleep where sleepwalking often starts). \n\nWhile most people grow out of it by late childhood, a small percentage continue to experience activity (one episode/month) in adulthood. \n\nThe kicker here is, you aren't aware you are having an episode while you're having the episode. When you're in REM, your brain effectively paralyzes your body so you are incapable of physically acting out your dreams - but you are capable of remembering them if they occur just prior to waking up. When you're in Phase 4, you are not paralyzed and you get up, move around, scream, talk, etc. while you're still dreaming. But, you also don't remember those dreams because you likely have a while to go before waking up, still.\n\nSources: personal experience, I'm 26 and have always sleepwalked and had night terrors. Studied this stuff in college to better understand it. \n\n_URL_0_ does a nice job explaining some of it, as well."
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4n7daz | when a program on my computer freezes, and i click "close the program" in the error message, why does it sometimes not close? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4n7daz/eli5_when_a_program_on_my_computer_freezes_and_i/ | {
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"A computer has a list of tasks it needs to do and when you click \"close\", you add a command to the end of that list of tasks. Unfortunately it's stuck processing an earlier task (whether it be an infinite loop due to a bug, or whatever), and can't reach the end of the list.",
"When you shut down a program you send a message to the program and ask it politely to shut down. This gives the program a chance to react and shutdown properly. If there is no response your operating system brings up the big guns and tries to kill the program by force which is not possible sometimes because the program uses some special resources and is stuck there (by a buggy driver for example). there are even programs which are completely unkillable.\n\nsome programs which appear to be stuck and not responding may be busy doing a larger operation and meanwhile forget to tell the operating system, that they are still alive. those kind of unresponsible programs are quickly killed.",
"Going to pretty much echo what [colonelsmoothie](_URL_0_) has said with an bit of an expansion;\n\nComputer programs 'freeze' or 'lock up' for several reasons, the most common of which is waiting for data or the task not being prioritised high enough, resulting in the program \"not responding\", because the program cannot continue executing the task until it has been given the data it wants. For example, when you're working on a big document, then you minimize it, go do something else like doing some research, and switch back to the document, it'll be waiting for cache files from the disk, or some objects in memory. \n\nQuite often in these instances, if you leave it, it comes back, the problem is when you click to close the program, the part of the operating system that manages all of the processes also tries to access some things about the program which adds to the big queue of requests for data.\n\nIf it hasn't crashed from waiting for something, it may well be a bug, and in this case your CPU may be trying to process something like an infinite loop at the same time as trying to be stopped. The task scheduler \n\nA tip if you're a Windows user; if you want to kill a program really quickly (and you're sure you don't care about losing any data), hit Windows & R, then type \"taskkill /im < processnamehere > /f\", where < processnamehere > might be winword.exe or notepad.exe. It forcefully abandons the process, and is almost instantaneous.",
"In ELI5 terms, because Windows is being a pussy.\n\nWindows has a few ways it can close a program:\n\n1. Ask the program to close\n1. Tell the program to close\n1. Sheepishly try to force the program to close\n1. Smite the program with the fury of a thousand Windows (which sounds good but is actually still not all that powerful)\n\nLet's use Notepad.exe as our example process. When you click \"Close the Program\" in the error message, it's only trying Method 2.\n\nIf you open Task Manager, click the Details tab, click the process, then click the End Task button, it is trying Method 3.\n\nIf you run:\n\n taskkill /f /im \"Notepad.exe\"\nthen it will try Method 4.\n\nUsually that does the trick, although if the process is a service it will likely restart itself so keep that in mind. But sometimes even that doesn't work, or sometimes the process is SYSTEM or a critical process that can't just be killed, so you have to reboot."
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1s64el | how does a radio station that transmits in different areas send the broadcast to other stations? | Like, when a station has multiple wavelengths, how does it send the broadcast if not by radio towers. And why do they use different wavelengths in different areas. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1s64el/eli5how_does_a_radio_station_that_transmits_in/ | {
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"FM radio has a fairly short range. Short enough that if you want to cover a large metro region you couldn't get it done with a single tower. The FCC regulates how close towers with the same frequency can be to each other, to make sure they don't interfere with each other. Because of this if you want to own coverage over a large area, and have it overlap (so you don't leave gaps), you need to have multiple different frequencies for that.\n\nSyndication is done by satellite for the most part.\n",
"I work for a Service Provider (SP) in North America in the support department for managed services (dedicated lines, SLAs, etc.).\n\nOne of our customers is a company that owns multiple radio stations and serves a larger rural area with a single \"station\" (multiple transmitters, same broadcasted information). They use regular guaranteed data services to deliver the transmission to the different towers.\n\nEssentially, they will have a SP deliver a dedicated line (DS1 private lines, Carrier Ethernet services, etc.) from their main office (including studio) to the building where they host their transmitter. They use that service to deliver the information to the site, where it is converted into a radio signal and transmitted. The customer I support has a few sites that all go back to the same office and are sent the same signal.\n\nAs for why they broadcast at different frequencies in different areas? It's because you apply for a broadcast license and spectrum license for certain regions. Thus you may get a license (frequency) for one region, but a different company has that license (frequency) in the other region. Thus you would get a different one.\n\nThe spectrum is saturated around heavily populated areas, while mostly unused in extremely rural areas. This means that if a company grows and decides to enter a heavily populated market, they will be squeezed into what spare spectrum is available in the region, regardless of their spectrum in another region."
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490mjs | establishment and anti-establishment in u.s. politics | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/490mjs/eli5_establishment_and_antiestablishment_in_us/ | {
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"Establishment as far as politics revolves around politicians that have been politicians for years if not decades. They are deeply entrenched in their political party and have a lot of influence and power and nowadays they are basically seen as corrupt or being in the pocket of one lobbyist group or another. \n\nAnti-Establishment is the platform that people like Trump are currently running on and it basically implies that these guys are outside the system and have the ability to shake things up and get the U.S. out of whatever situation it might happen to be in. \n\nFor a long time experienced politicians were typically seen as a good thing but money in politics has gotten so prevalent here in the States that a lot of Americans have begun to really despise politicians that have been in congress for decades."
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zb1d9 | what happens in the brain of a schizophrenic? | How is it different to a "normal" brain? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/zb1d9/what_happens_in_the_brain_of_a_schizophrenic/ | {
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"Unfortunately we don't really know. Part of the problem is that schizophrenia is diagnosis of *symptoms* rather than underlying conditions. \n\nThere is evidence to suggest that many schizophrenics are overly sensitive to dopamine, and many of the anti-psychotic meds that we use to treat it are dopamine blockers. However there are also some anti-psychotic meds that block serotonin. There's also a newer theory that the brain might be less sensitive to glutamate, which is another neurotransmitter. Physically, the person's hippocampus, frontal lobes, or temporal lobes may be smaller which lead to impaired memory and cognitive ability. There are also cases where a person can be diagnosed as \"schizophrenic\" and have *none* of these, and we have absolutely no clue. \n\nSo... to answer your question - too much dopamine, too much serotonin, too little glutamate, smaller specific brain regions, or none-of-the-above.",
"I have absolutely no experience in dealing with schizophrenics, so I am not the best source for this, but I have read numerous articles written by and for schizophrenics who want their voice to be heard. I know a thing or two, but certainly am no expert. \n\nWhat I have realized is that no two schizophrenics are alike. Most have auditory hallucinations while some (very rare) have visual hallucinations. There are paranoid schizophrenics and other types that are more mild. \n\nAn auditory schizophrenic will hear voices in their head. Some report that the voices are \"traveling at 100 MPH\" and some report that they are very clear and discernible from their own thoughts. However, many say that there is no clear distinction between the things that they hear, and the thoughts that they think. So imagine you're sitting in bed and you think to yourself, \"Hmm. I want a chicken sandwich.\" The thought in your head that said that would sound completely the same as the voice telling you that there is a man hiding in your closet, or that you shouldn't trust the chicken company because they poison their food. \n\nYou would have no way of telling what you're thinking and what is being \"told\" to you. \n\nVisual hallucination can range from something VERY mild to just seeing things move every once in a while, to seeing people who aren't really there and you are absolutely convinced that they are real. Visual hallucinations aren't too common, so I'll just leave it at that. \n\nNow, in my opinion, paranoid schizophrenics are generally the dangerous ones. Basically what that means is that they think someone or something, somewhere is out to get them. Whether that be the CIA or some fictional monster, it completely depends on the person. Paranoid schizophrenics genuinely believe that someone is trying to hunt them down or kill them or capture them, etc. These types of schizophrenics are usually the ones to act on their actions, because they are afraid for their own lives. This can lead to killing themselves, harming others, building a bomb because, well, that's what the voices are telling him to do...etc. \n\nIt really can be a range of things, so I'm sorry if my answer got a little long. \n\n**Seriously.** If I am wrong about anything (remember, I am no expert), please tell me and I will edit out whatever I got wrong, but I'm 90% sure that everything I have posted here is correct. \n\nHope that helps answer your question!",
"I recently heard an interview (I think it was on Science Friday- I'll look for it) where the researcher suggested that schizophrenia may be a disorder of time perception: they are confused about the order in which event occur. This means something happens, and the patient reacts, but the patient perceives their reaction as coming before the event. The researcher thought this could explain why patient's think they hear voices, when in reality, it is their own internal monologue they're hearing.\n\nEdit to add: here is the link the David Eagleman on science friday. He talks about schizophrenia and the time delay\n_URL_0_",
"The brain cannot distinguish between reality and non-reality (such as dreaming), this is normal. People can learn to wake themselves from a bad, unwanted dream. \n\nIt seems to me that the defect is in what is known as the midbrain whose function, among other things, keeps you from walking around while you are dreaming. \n\nI know nothing of medicine, these are just some facts that I know. I also think it is truly sad that we can get to mars, but cannot help people that suffer with schizophrenia, other than doping them out of life."
]
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| []
| [
[],
[],
[
"http://sciencefriday.com/segment/08/24/2012/david-eagleman-gets-inside-our-heads.html"
],
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|
|
d6cw6x | what is exploit development? | I want to know what exactly is Exploit development in a real job. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d6cw6x/eli5_what_is_exploit_development/ | {
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"Exploit is literally just that. Using something in a way it wasn't designed for. Lighting a cigarette using a toaster is an exploit for example. In the computer world an exploit could be for example a search tool with a text field that for one reason or another lets you run program code or run queries to a database directly. Even deeper down the rabbit hole you might find out that you can crack passwords by listening to certain RF signals the processor makes and so on. \n\nSo exploit development is practically just figuring out flaws in a certain system. There's probably a systematic way into it as well but that's where my knowledge ends",
"This feels like a let me google that for you. Here's a decent description: [_URL_2_](_URL_2_) \n\nBasically, identify a flaw in the system. The article uses fuzzing as an example, which basically means that you send random data to an api or listening port, and then see how far you get. For every byte you send, the listening protocol thinks you are:\n\n1. Speaking its language\n2. Definitely not speaking your language, and probably disconnects you\n3. Is fooled into doing something unexpected (by the programmer)\n\nIf you find option 3, you may have found something exploitable. You can reverse engineer the code, or just experiment and see if you can get it to do something specific and to your advantage. With an identified exploit (basically access to undefined behavior), and an effort to develop it into something that you can use to your advantage, you are doing Exploit Development.\n\nI'm going to write this unpleasant thing in an effort to help you: If you are majoring in Information Security, and you don't know this or how to find it on the Internet, you have much to learn. Since I know nothing of your intelligence, I will assume you are smart, so I would start with something like Grit. Check out this video: [_URL_0_](_URL_1_)",
"1. Find a loop-hole in the rules (bad implementation, design flaw, human laziness or ignorance)\n2. Learn how to use this loop-hole to do things not meant to be done (gaining information or access)\n3. ???\n4. PROFIT",
"As I see it, you first find a vulnerability or a problem. For instance, you find out that if you enter a negative quantity of hamburgers in a website, you get a negative cash amount. So you balance the cost of a hamburger with another one so that your amount becomes 0, and you get the hamburgers for free.\n\nAn exploit would be a tool that makes it possible to use that vulnerability easily. Sometimes an exploit's purpose is just to test if the vulnerability is there, sometimes it goes beyond that. An exploit is a program, and as such, someone has to write it in some programming language. Usually developing this kind of tools requires a pretty good knowledge about networking, but hey, it could be a local exploit so maybe instead of that you would need to learn stuff like how the operating system manages system memory, or user permissions, or whatever. Therefore, there isn't a fixed set of stuff that you need to know in order to write exploits, it depends on the kind of vulnerability you are exploiting. But yeah, you should probably be somewhat good with some programming language like C or maybe python or ruby."
]
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| []
| [
[],
[
"https://www.ted.com/talks/angela\\_lee\\_duckworth\\_grit\\_the\\_power\\_of\\_passion\\_and\\_perseverance?language=en",
"https://www.ted.com/talks/angela_lee_duckworth_grit_the_power_of_passion_and_perseverance?language=en",
"https://null-byte.wonderhowto.com/how-to/exploit-development-everything-you-need-know-0167801/"
],
[],
[]
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2h6kal | how are vitamins and supplements, that the body makes naturally, man-made? | I was drifting off into space while staring at my bottle of melatonin and started thinking. What are these things even made out of? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2h6kal/eli5how_are_vitamins_and_supplements_that_the/ | {
"a_id": [
"ckpucvb"
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"Firstly, your body doesn't naturally make vitamins, that's why you need to eat them. \nSecondly, most of them are just extracted. Most of the things we grow or produce for food, of necessity, have those vitamins in. Sometimes it's easier to just take them out. \nThirdly, you can make almost all of them artificially, but its a different process for each of them. It's usually a complicated process requiring multiple steps and a deep knowledge of organic chemistry. "
]
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| []
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[]
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|
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5g6y08 | why taiwan and united states have severed diplomatic ties. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5g6y08/eli5_why_taiwan_and_united_states_have_severed/ | {
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"text": [
"Because the People's Republic of China (usually just called \"China\") gets really mad when other countries recognize the Republic of China (Taiwan). The US has decided to not recognize the ROC to avoid antagonizing the PRC.",
"For decades, the US claimed that the real government of China was in Taiwan. Taiwan liked this, since they felt the same way. The mainland didn't agree, and thought that instead that Taiwan was part of China as it always had been.\n\nWhen Nixon went to China, the US eventually agreed that mainland China was indeed the \"real\" China. After a long time that meant agreeing that Taiwan wasn't. So what was Taiwan? That's a question the US would rather not answer.",
"All good answers.\n\nPart of it too is trade. PR China was seen as a massive purchasing opportunity, that is, as their people found themselves with a disposable income, buying American products was a thing.\n\nAnother part was military navigation both aerial and nautical.",
"The Chinese Civil War ended in about 1950 with the Communist insurgents taking control of the country. The losing side retreated to the island of Taiwan, where they continued to claim to be the legitimate government of China. The US recognized that claim until 1979 (though signals of the change started in 1971-72). The US now recognizes the Communist government as the legitimate government of China.\n\nBoth the mainland Chinese government nor the Taiwanese government continue to consider mainland China and Taiwan to be the same country. The Taiwanese government continues to claim to be the legitimate government of the whole of China. The mainland Chinese government continues to claim Taiwan as part of China.\n\nSince neither side believes that they are separate countries, the US has determined that it cannot recognize both governments.\n\nThat said, there is definitely a relationship between the US and Taiwan. It's not as if the US refuses to deal with Taiwan at all. It's just a complicated, delicate diplomatic situation.",
"They haven't really. There are no official relations, but the informal relations aren't actually all that informal. They're done by the American Institute in Taiwan, which is staffed by foreign servants of the US state department.\n\nThe reason this is the case is that the Mainland Chinese have the One-China policy, which dictates that Taiwan is part of China. So, Mainland China will not have official relations with any country that also has relations with Taiwan. It's silly, but Mainland China has a lot of pull, and quite a few countries feel it's worth the effort to humor them. ",
"I am Taiwanese, so I'll try to explain it from our perspective. After being released from being Japanese colony after World War II, the status of Taiwan was not yet determined (whether it was to be a separate nation or given to China). Right after World War II, there was the Chinese Civil War, which the Chinese Communists (PRC) won. The Nationalists fled to Taiwan after losing and established their base to retake China in Taiwan (obviously not being very friendly about it ([February 28 Massacre](_URL_1_)). Bear in mind there were native Taiwanese already in Taiwan (Chinese immigrants living in Taiwan for hundreds of years and aboriginals), which were suppressed by the Nationalists, in a 38 year long period of martial law. Up until 1979, the US recognised Taiwan as the real China under the Nationalists, after warming US and PRC ties, the US recognised the PRC as the real China. Meanwhile, the Nationalists refused to rescind their claims to Mainland China, even though in this day and age that is clearly ridiculous. Even after becoming a **democracy** in 1996, it is impossible to take back those territorial claims on China anymore, because doing so would be treading too close to Taiwanese independence. I cannot stress enough that *Taiwanese claims to all of China are forced on us, first by the authoritarian Nationalists and now by the PRC*. In the event of such independence, the 2005 anti-secession law in China would automatically be triggered authorising the use of \"non-peaceful means\" against Taiwanese independence. Although \"non-peaceful\" means aren't anything new: [1st Taiwan Strait Crisis](_URL_2_), [2nd Taiwan Strait Crisis](_URL_0_), [3rd Taiwan Strait Crisis](_URL_3_).\n\ntl;dr....Taiwan used to be recognised as the real China, the States switched to the PRC but kept close ties with Taiwan. The issue regarding our status remains to be resolved. If there are more questions, feel free to ask, I'll do my best to explain."
]
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[],
[],
[],
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"https://en.wikipedia.org/wiki/Second_Taiwan_Strait_Crisis",
"https://en.wikipedia.org/wiki/February_28_Incident",
"https://en.wikipedia.org/wiki/First_Taiwan_Strait_Crisis",
"https://en.wikipedia.org/wiki/Third_Taiwan_Strait_Crisis"
]
]
|
||
1nlzkm | why would a business limit the amount of products a person can buy? (e.g. "maximum 5 per customer") | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1nlzkm/eli5_why_would_a_business_limit_the_amount_of/ | {
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"Usually they are offering something at below normal cost as a promotion. Say a widget costs ABC company $10 to buy and they sell it for $20. They might offer it for sale for only $10 as a promotion in hopes that you'll come into the store and buy other things.\n\nHowever since it is a good deal you may decide \"I only need 3 widgets but since it is so cheap, I'll buy 50 and sell the rest on eBay for $15.\" So you go in and clean out the shelves and the next person comes in to buy a widget and gets mad the store is sold out and leaves, buying nothing.",
"Stores will mark some products down to a low price to bring people in to the store, in the hope they will purchase other products while there, on impulse or otherwise.\n\nTo ensure they have enough to last the sale, because they are required to stock a reasonable amount, and because they want more people coming into the store, they will limit the number of products to any one person. \n\nUsually they're making a loss on these products after overheads and are counting on increase in total sales to make up the difference."
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485jgq | why are nascar tracks an oval as opposed to something like a figure 8 so they can make right turns as well. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/485jgq/eli5_why_are_nascar_tracks_an_oval_as_opposed_to/ | {
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"text": [
"NASCAR has two road circuits in the schedule: Sonoma Raceway and Watkins Glen.\n\nFor the most part, though, they use oval tracks because that's what people like to see (in general, in America). At an oval track, you can see pretty much all of the track from your seat, as opposed to being at one corner on a long road track. Oval tracks generally have higher speeds and close pack racing.\n\nAnd then finally, it's tradition. NASCAR began on dirt oval tracks, and moved on from their. It's a sort of, that's the way it's always been.\n\nIt's like asking why drag racing takes place on a straight quarter mile track. It's just the nature of that form of racing. It's like asking why water is wet. It just is."
]
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| []
| [
[]
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|
||
4x0c5s | why is cantonese treated as a dialect by the hong kong government? | Hong Kong's official languages are Chinese and English. I'm aware of the British's influence on Hong Kong that created the need for inclusion of English as well as the fact that Mandarin is the predominate Chinese language used in Chinese media, so I can understand why the entire language family would be included as it implies both Mandarin and Cantonese. However, Hong Kong's only recongised language is Cantonese, and although I'm not a Hong Konger, I think that this is very insulting to the main Chinese population in Hong Kong, as the majority of them are descendants from people from the Canton region and an overwhelming majority speak Cantonese and indulge in the culture. I just can't wrap my head around why they would specifically label Cantonese as a recognised language as if it was a dialect and not a language within itself. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4x0c5s/eli5_why_is_cantonese_treated_as_a_dialect_by_the/ | {
"a_id": [
"d6bm93l"
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"score": [
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"text": [
"I agree with you that Cantonese is a separate language from the other Chinese languages.\n\nThat being said, it's political. China continues to claim that the varieties of Chinese, such as Yue, Wu, Minnam etc are dialects because it helps to unify the country. If, they were (rightly) called different languages, then you'd add another factor to destabilize national identity.\n\n"
]
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48saaq | how can movie producers hire actors of a specific race or sex without it counting as racial/sexual profiling? | "White male receptionist wanted for hire" - illegal
"White male actor for roll in new film wanted" - legal
How do these laws work?
| explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/48saaq/eli5_how_can_movie_producers_hire_actors_of_a/ | {
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"text": [
"Anti discrimination laws usually have exceptions for acting and other jobs where race is deemed relevant to the job.\n\nNot much else to it. The answer is simply that the law allows you to discriminate based on race for that particular type of job.",
"Things like movie casting (and other \"reasonable\" racial/gender qualifications for hiring) are specifically excluded from discrimination laws.",
"They make exceptions for movies because they have to, since movies require specific kinds of people. Same for modelling.",
"There's an exception to equal employment laws that allows employers to discriminate on grounds they normally couldn't for \"bona fide occupational qualifications.\" Basically, if your race, sex, religion, etc. is important for the nature of the job, the employer can discriminate. For example, a Catholic school could require all of its teachers and administrators to be Catholics, but probably couldn't require that of its maintenance staff. Similarly, a producer can hire a person who has to physically look a certain way for an acting role without violating employment laws.",
"It's a lot more complicated than \"counting as racial/sexual profiling.\" There is no law against being racist or sexist generally, but federal and state law prohibits specific forms of discrimination in employment (among other areas).\n\nThe major statute is the federal [Civil Rights Act of 1964](_URL_0_). It holds that, for employers covered by the act, \"it shall be an unlawful employment practice for an employer to fail or refuse to hire or to discharge any individual, or otherwise to discriminate against any individual with respect to his compensation, terms, conditions, or privileges of employment, because of such individual’s race, color, religion, sex, or national origin.\" ([42 U.S. Code § 2000e–2(a)](_URL_1_)).\n\nHowever, it *also* clarifies that \"it shall not be an unlawful employment practice for an employer to hire and employ employee ... on the basis of his religion, sex, or national origin in those certain instances where religion, sex, or national origin is a bona fide occupational qualification reasonably necessary to the normal operation of that particular business or enterprise.\" (42 U.S. Code § 2000e–2(e)).\n\nSo whenever you can prove that something like race is a \"bona fide occupational qualification,\" you can discriminate based on it. The courts have found that in acting, appearance matters--actors who are white or black, male or female, are not the same. Thus you may lawfully discriminate based on these factors. But you could typically not discriminate based on religion, since an actor's religion usually has nothing to do with his qualification for a role.",
"You don't need to be a white male to be a receptionist. You need to be a white male to play the role written as a white male in a movie.\n\nProfiling has limits for pretty obvious reasons. Job providers have certain people in mind for a role, which is why a 4.0 Pre Med major can't sue a company for hiring a 3.0 Accounting Major to work in the Accounting department.\n\nActing has more wiggle room for this for pretty obvious reasons, roles are written to be something, and they have every right to cast it as such.",
"Related question: Why can movie producers hire children as actors, in spite of child labour laws?"
]
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[],
[],
[],
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"https://en.wikipedia.org/wiki/Civil_Rights_Act_of_1964",
"https://www.law.cornell.edu/uscode/text/42/2000e%E2%80%932"
],
[],
[]
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9kkp6y | the cholesterol in egg and just how much it impacts cholesterol levels. | Debating with a friend over egg being healthier than McDonalds, but she won't believe me. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9kkp6y/eli5_the_cholesterol_in_egg_and_just_how_much_it/ | {
"a_id": [
"e6ztdso"
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"score": [
14
],
"text": [
"Dietary Cholesterol is no longer thought to contribute much if anything to blood cholesterol level. Blood Cholesterol is made by the liver and not taken out of the food that we eat. "
]
} | []
| []
| [
[]
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|
|
8is2ju | what is the feeling when your balls shoot into your stomach? | You know that feeling, when you see something so painful that it feels like a hollow opening is in your lower intestine and it feels like your balls have shot upwards. Every guy knows this type of pain, but what exactly is happening. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8is2ju/eli5_what_is_the_feeling_when_your_balls_shoot/ | {
"a_id": [
"dyu8wib"
],
"score": [
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"text": [
"I believe it's your brain sending a message to your balls to retract because it can't handle being a male. "
]
} | []
| []
| [
[]
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|
|
2d7zf7 | how some less muscular people can lift a lot heavier weights than much muscular people? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2d7zf7/eli5_how_some_less_muscular_people_can_lift_a_lot/ | {
"a_id": [
"cjn1gmr"
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"score": [
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"text": [
"When I had a weight training class, I was told that I could lift weights to become stronger OR to have more impressive-looking muscles, but not really both at the same time. More muscle is more power, so any working out will make you capable of moving more weight, but different training leads to different results. At the end of my class, I looked a little bigger but not to the point that strangers remarked on it. I sure could carry 80 pound bags of cement up the stairs though, no problem!\nAlso, and this is really important, knowing how to use what strength you have is just as important as your actual strength. Being able to tell where the balance point on something is, knowing how to shift something without lifting it much, how to apply your strongest muscles to the task, etc. I spent years working in a wood and metal fabrication shop where I was usually one of the smallest people on the floor. Learning how to 'carry my weight' without giant arms was a vital skill for me.\nNow my spine is messed up and I can't support as much as I can lift, so I have to be even more careful to use my brain before my body. I'm a big fan of levers!"
]
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| []
| [
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|
||
4hkoqv | how end to end cryptography works? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4hkoqv/eli5_how_end_to_end_cryptography_works/ | {
"a_id": [
"d2qegnz",
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"score": [
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8
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"text": [
"There's a mathematical formula with two numbers that you generate on your device. One of the numbers is used to encrypt the message (you can tell that one to the whole world) and the other one is used to decrypt it (you keep that one a secret- it never leaves your control). There's no good way to find the secret number from the public number that we know of- if anyone finds a way, we stop using that formula and move on to something else. ",
"The literal ELI5:\n\nAlice wants to send a message to Bob, but she wants to make sure only Bob can open the message.\n\nAlice has a padlock that only she can open, and she knows Bob has a padlock that only he can open.\n\nAlice puts her message in a box, and puts her padlock on it, and sends it to Bob.\n\nBob can't open it, but he can put HIS padlock on it, and send it back to Alice.\n\nAlice can't open it now, but she can remove her padlock, and send it back to Bob.\n\nNow Bob can open the padlock and remove the message.\n\n"
]
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[],
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||
9nqb9s | do adults have more skin than newborn babies? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9nqb9s/eli5_do_adults_have_more_skin_than_newborn_babies/ | {
"a_id": [
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"text": [
"No just the same as your bones don't stretch out as you get taller and wider. You grow more. "
]
} | []
| []
| [
[]
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|
||
5g5pcy | wastewater treatment and city water systems | I guess I'm just wondering how much of the water that goes down the drain in the shower, sink, washing machine, etc. is actually wasted. What percentage comes back through my city water pipes to use again? I try not to use up a lot of water but I realized I don't exactly understand what my efforts are doing. I live in Michigan so I am concerned about water and conservation and quality of water. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5g5pcy/eli5wastewater_treatment_and_city_water_systems/ | {
"a_id": [
"dapodpf",
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"score": [
2,
4
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"text": [
"It all comes back eventually....as rain. Once it leaves the waste system, it's cleaned and dumped into nearest body of water, river or lake or ocean. The intake and discharge are not in the same body of water. You intake upriver, and dump downriver. It just sucks to be the next city downriver that has to intake.",
"All of it eventually (short of someone performing mass electrolysis to make hydrogen and oxygen and burning it in space or something similar). You're not really wasting water, you're wasting the energy that was used to purify the water, store the water, and deliver the water to your door. "
]
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2o3ds4 | wrestling, it's scripted, but is it staged? is that happening in the ring a real fight or are wrestlers really good stuntsmen? and why sometimes blood happens? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2o3ds4/eli5_wrestling_its_scripted_but_is_it_staged_is/ | {
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"text": [
"It's staged in that the winner is predetermined but other than that, it's up to the participating wrestlers to work out the \"play-by-play\". \n\nFor instance, I might put you in a headlock and whisper into your ear \"finisher\" to let you know I want to set you up for my finisher, or \"turnbuckle\" to let you know to take a hit on the turnbuckle. \n\nAccidents and mistakes do happen, where a wrestler might setup a move improperly and cause legitimate damage to the other wrestler, at which point the referee will jump in the secret conversation to find out if he needs to stop the match.\n\nThe blood is either staged or legitimate. The staged blood *is* their real blood, they use a technique called \"blading\" where they might hide a razor blade in their wrist tape (or the referee might have it, or the opposite wrestler might have it) and they cut right above their eyebrow. Mixed with their sweat, it makes it look as if they're bleeding way more than they actually are. Legitimate blood occurs when a wrestler actually hurts the other one (called a bump) or takes the blading too far/too deep. ",
"Wrestlers call the moves they are about to make. Like one will say to the other \"Into the ropes, then bodyslam\" and that's what they'll do. Referees are sort of timekeepers, in the sense that they'll let the wrestlers know when it's time to wrap up a fight. Blood happens because the wrestlers literally cut themselves with razor blades, as discretely as possible obviously.",
"The outcome is scripted did but the actual physical contact is real. When a guy takes a chair shot to the head he is really taking a chair shot to the head. When the Undertaker threw Mick Foley off of the cage 20 feet below into a table Mick Foley was really thrown 20 feet off the cage into a table. You can't fake that.\n\nSpeaking of Mick Foley, I remember him telling a story about a bunch of stunt men looking at that footage and wondering how the hell he did it. He wondered how he broke the fall and what kind of support props were there to help him take the impact. He simply explained to them that there was none of that.",
"For some more insight to how calling a move works, there's a series on Youtube and Dailymotion called Botchamania. They show a series of botched moments from wrestling, and at least once an episode run footage where you can hear the wrestlers calling moves under their breath. ",
"Almost completely staged. They are great stuntmen. While some moves may be more real than others, like a chair slam or such, they have a lot of tricks to make it look worse than it is.\n\nFor instance, watch their feet as they punch each other; they're slamming on the ground to make a louder noise so it seems more impressive. Or look [here](_URL_1_) at the fake fall, and the later \"bodyslams\" where they land on their hands/knees and barely even touch the wrestlers on the ground. (Watch the one on the right especially)\n\nAnother great example [here](_URL_0_), the act is a big piledriver type move, but he lets go of him early, so he can land safely and slap the mat making it sound like he hit it. [freeze frame](_URL_3_)\n\n[Even better](_URL_2_), here's a perfect example of the kick-hop - all the force is going into the foot that hits the mat as they tap the guy on the floor. Just after 30 seconds, you can see a fake kick as the bunny enters the ring; the other wrestler anticipates it and sends himself backwards with it.\n\nThis isn't to say that some of these things don't require a lot of skill or athleticism, they've definitely had to work at this to do it well, but it's still mostly an act :)"
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3ib2i7 | how does one get into preforming magic if magicians dont share their secrets? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ib2i7/eli5_how_does_one_get_into_preforming_magic_if/ | {
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"A magician won't share their secrets to just anyone, you have to work at it to be able to know the in-depth secrets to doing illusions. It's still a rather tight nit operation, even with a lot of the basics out in public knowledge the tricks still work, because people don't know how these tricks scale up.",
"I just watched a youtube video from Ana Akana where they interviewed a magician. Basically, learning the basics of magic are simple and readily available in books. Once you become proficient, you meet more and more in your field and you learn from each other.\n\nAs said in the video, the trick is easy, it's the delivery that's hard.\n\n_URL_0_",
"I started learning the basic fundamentals, i visits regularly to a magic shop and bought different tricks. Once i got a good relationship with the shop owner, i asked them for some advice. I google for different magicians and look at their performances. It depends what type of magic you are focusing on. There are stage, street, close up, mentalism and etc.\n\nStart with beginner tricks, once you get the hang of it, go to next stage. ",
"Former semi-pro closeup magician here.\n\nThere are lots of ways one learns magic or gets better at it.\n\nFirst off, there are plenty of magic books and videos available on the market, aimed at every level from beginner kids to advanced pros. Secondly, you can walk into any magic shop on the planet and walk out with an armload of secrets--as long as you have cash or a credit card. You don't even need to know the secret magician's handshake.\n\nThere are lots of magic clubs and professional organizations that have educational programs. The Magic Castle in Hollywood offers a beginning magic class for non-members (that's how a lot of people become members).\n\nAnd a lot of pro magicians teach, either private tutoring, or classes. Magic clubs frequently have teaching lectures.\n\nHowever, magic secrets are not the REAL secret of magic. The real secret is the performance: the best trick in the world will fall flat if the performance sucks, and a good performer can take a cheesy trick and turn it into a stunning performance. If you can't learn how to perform, there's no point in learning magic at all.\n\n"
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2i9w25 | i have a lisp, but in my head it sounds like i'm pronouncing it properly. why is this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2i9w25/eli5_i_have_a_lisp_but_in_my_head_it_sounds_like/ | {
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"This is an interesting phenomenon. I personally have my own idiosyncratic accent (not actually a lisp) but I always sound as if I am speaking perfectly, to myself. However when I listen to a tape-recording of myself, I can hear the accent. It is also true that everybody sounds different to themselves on tape, as compared to listening to themselves speaking live, because we get a much richer sound from direct bone conduction of sound, from the larynx to the ear, when we are speaking. Recordings are a somewhat washed-out version. Another reason for this difference in perception is simply the way our attention focuses. When we speak, we are focused on speaking, and when we are just listening (as for example, to a tape recording of ourselves) then we focus on listening. So, try listening to a recording of yourself speaking, and see what happens.",
"I don't have any speech impediments, but sometimes when I'm tired or hyper, I try to speak so fast that not all the syllables come out properly enunciated. About half the time I know my tongue dun goofed, but the other half, a good part of my brain is like \"yea, no, that was good, keep goin\", but the part that remembers what the muscles in my mouth just did go \"hey wait a sec, there's no way that came out right...\".\n\nI'd chock it to parts of your brain not communicating with one another.",
"When you speak you are also thinking the words. Your inner voice is saying the word inside your mind. It doest make mistakes like your mouth do. ",
"The areas of the brain that control language comprehension (including intent) and the parts that control the muscles to say the words are independent.\n\nThere is a disorder (forget what it's called) where a person can say multi-syllabic words with perfect pronunciation that is entirely unrelated to what they intended to say. And as far as they're aware, they are being completely coherent.",
"This is a link to an interesting Radiolab show about someone with a similar experience, but even more extreme. The guy in the story thought he was talking at the same speed as everyone else, but when he heard his voice on tape, it was incredibly slow. _URL_0_",
"I'm interested in the right answer to this as well. I was in speech therapy for a lisp until I was 14 because \"it sounded right to me\". The \"ttthhhh\" and \"ssss\" to me sound almost identical (even now), it's just a different area of the mouth where air is being pushed out.",
"This is very annoying for someone with a cleft lip (google it). I hate hearing myself in videos.",
"I was born with what people refer as \"tounge tied\" the actual term is a crazy strange word. I had surgery at 8+ constant speech therapy and it took me until I was 15 or so to correct it to perfection. It was pretty bad until then. It was strange cause in my head I couldn't hear it so it irked me to hear myself on video. Now, words I know that would come out strange when I had the lisp, I have to say in my head before saying it out loud. Its a reflex now and I don't even realize I'm doing it. But I essentially feel like I had to train my tounge and brain to work together properly. I also slow my speaking when I say certain words just to make sure it comes out right.",
"This is a common phenomenon, not confined to speech. For example, I play piano, and often record myself. When playing back the recordings, not only do I notice problems or mistakes that I was oblivious to when I was playing, but the whole performance sounds significantly different.",
"From a neuroscience perspective, your brain has learned to take a particular range of sounds and collectively understand them as one sound. You probably already know several examples of this: a Japanese speaker might not be able to hear the difference between an R and an L. The same thing goes for many Spanish speakers and the letters B and V.\n\nSo what likely happened is that as you grew up, you couldn't/didn't pronounce an S the way most people are taught to. (I'm just assuming it's an S lisp.) But you knew you were trying to say an S, so your brain eventually grew to include whatever sound you made as within the range of sounds that register as an S. Whereas the rest of us, to whom it sounds like you have a lisp, have a tighter range of acceptable S sounds.Your S sound might register in the TH range for many of us, for example. \n\nThe key here, though, is the range. Everybody says every letter very slightly differently. So as you grow up, your brain learns to group a range of sounds together as put them all in the \"S\" category. You have ranges for every letter, but everybody's range of what \"counts\" as what letter is very slightly different as well. \n\nSo you can think about it like this: your brain is a little more lenient on what counts as an S, whereas other people's brains are more stringent.\n\nEDIT: For a really tremendous ELI6 explanation, see the comment by /u/hauntedcandle.",
"I always assumed that people with lisps knew/could hear the way they sound. ",
"I have such a hard time pronouncing a certain combination letters in succession. One for example is R and W: rear wheel, Mr. Williams, real world. There are other combinations but that's the most prominent. I usually slur through those words. I learned Spanish at home and English at school (everywhere else). I've always wondered if Spanish interfered with my English pronunciation. I don't have an accent in either language, however, pronunciation issues in both. Would a speech pathologist be helpful in my situation? Any other Spanish speakers have issues or did I just get dropped on my head one too many times?",
"People in my home town often ask me if I'm from somewhere else. I'm not. I've traveled a little, but have never lived somewhere else for more than 10 days. \nSo, I guess I'm in the same boat.",
"Hey man just popping in. I'm 30 and to myself I've always talked perfectly. I made an ice bucket challenge video and noticed I have a slight lisp. No one ever told me and I never really listened to my voice before. Now I hear it all the time..",
"2nd year speech-language pathology graduate clinician checking in here.\n\nIn therapy we work on repetitive motoric exercises to establish what a good /s/ sound is at the isolated phonemic (sound) level. Once it is established, the correct sound is transferred slowly and steadily to other higher levels of speech (nonsense monosyllabic sounds, monosyllabic words, multisyllabic words, phrases, sentences, and extended connected speech). This process is slow and laborious and must be done for the /s/ in all positions (initial, medial, final word positions, and blends).\n\nAll throughout this process, we often ask the client to intentionally produced a \"lisped\" /s/ so that internal perceptual/physical contrast is established for the speaker. We do this so the correct phoneme (sound) is entered and established in the client's \"phonetic inventory\" of speech. This allows for greater long-term success and generalization of the sound production, plus it shows the client that they have the ultimate control over their speech sounds.\n\nTL;DR - You don't know you're producing an incorrect phoneme (sound) because your motor and cognitive plans haven't been exposed and trained to know what the correct sound is because your articulatory development erred in some way during your speech development (unless the deviance is due to an anatomical/physiological difference).",
"Now I'm paranoid that I have lisp and don't even know it.",
"Watch The Kings Speech?^sorry"
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8tjvfl | why are things that are distant (1 mi+) have a blueish fog? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8tjvfl/eli5_why_are_things_that_are_distant_1_mi_have_a/ | {
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"It's the same reason the sky is blue. The particles in the air reflect a blue wavelength of light because they absorb all others. This effect can be seen at large distances because there is enough atmosphere inbetween the observer and the obejct"
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eyuapz | how are there as many even numbers as there are numbers? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/eyuapz/eli5_how_are_there_as_many_even_numbers_as_there/ | {
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"Every even number can be written in the form 2k, where k is an integer (whole number). Since there are infinitely many whole numbers and each can be used to generate an even number (by plugging it into the formula for k) there are the same amount of even numbers, infinitely many.",
"Imagine a list of all whole numbers\n\n1 2 3 4 5 6 7 8 ...\n\n... continuing on forever. Now imagine a list of all even numbers\n\n2 4 6 8 10 12 14 16 ...\n\n... continuing on forever. How do we know these lists, though both infinite, are actually the same size?\n\nWe do what mathematicians call a \"mapping.\" If we can take every single number in the first list, and map it to a number from the second list, in such a way that each number in each list is used exactly once, then we know both lists are the same size.\n\nFor these lists, it's easy: each number *n* maps to *2n*:\n\n* 1 - > 2\n* 2 - > 4\n* 3 - > 6\n* 4 - > 8\n* etc\n\nIf you go vertically down the left side, you see our original list of all whole numbers. If you go vertically down the right side, you see our original list of all even numbers. They go side by side in perfect stride forever, and thus are the same length.",
"It has to do with how we define counting. From a very mathy perspective, counting is just matching things up one-to-one with the natural numbers. The natural numbers are just the counting numbers (1, 2, 3, 4, ...).\n\nFor example, to count the letters in the alphabet, I match them up to the natural numbers and see where they stop.\n\n 1 2 3 4 5 ... 24 25 26\n A B C D E ... X Y Z\n\nNow that we've matched up the letters and numbers, we can see that there are 26 numbers.\n\nThe reason there are \"the same amount\" of even numbers and natural numbers is simply because we can match them up one-to-one, and have none left over in either set.\n\n 1 2 3 4 ...\n 2 4 6 8 ...\n\nThere is never a natural number that does not have a corresponding even number. Since we define counting as matching things up with the natural numbers, we consider there to be the \"same amount\" of each.\n\nIf you want to turn this fact into a party trick, you should learn about the [Grand Hotel](_URL_0_) problem. Infinity is already a mind bending concept when you first encounter it, so this can be a fun thing bring up at a party."
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144tos | what is washington d.c, and why is it the capital if it is not even a state. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/144tos/what_is_washington_dc_and_why_is_it_the_capital/ | {
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"The national capital is intentionally not a state, because any state which was also the national capital would have undue influence in national politics.\n\nSo they took land from several states sort of near the middle of the (important original) states, and made a little district to have the capital city in.",
"Washington D.C. is the national capitol, and is a US Territory the same as say Puerto Rico.\n\nThe reason it is not a state is to not give any one state to much power, or make any 1 state the \"head\" or \"Best\" state etc. No favorites! "
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e8o0wm | how does potassium balance out sodium in maintaining a person's blood pressure? i've read that it has something to do with osmosis across the cell membrane. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e8o0wm/eli5_how_does_potassium_balance_out_sodium_in/ | {
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"Renal physiologist here.\n\nA lot of evidence is showing that increased potassium intake can help hypertension by lowering sodium in the body. It actually comes as a bit of a surprise, because high potassium elevates aldosterone, a hormone that results in getting rid of potassium in the kidneys but also promotes the reabsorption or retention of sodium. But you can't argue with evidence.\n\nThe mechanism with how this works remains unclear. The most prominent hypothesis for now is that potassium can downregulate or reduce the NCC (sodium chloride cotransporter). I won't get into the molecular mechanism, but it has to do with the voltage or potential across the cell membrane altering chloride in the cells.\n\nMany non renal mechanisms have also been proposed. Quoting a study directly, these include reduced renal renin release (a hormone axis regulating blood pressure), decreased vascular smooth muscle cell proliferation (reduce muscle cells in the blood vessels, which normally function to constrict the vessels and elevate blood pressure), reduced vascular smooth muscle cell migration, decreased free radical formation, reduced low-density lipoprotein cholesterol oxidation, decreased platelet aggregation, and improvement of endothelium-dependent vasodilatation and reduction of oxidative stress. I didn't explain how some of these mechanisms can lower blood pressure because they're quite complex and quite indirect. Some even proposed that the sodium potassium pump may be at play for this antihypertensive effect: this pump is found almost everywhere and it extrudes or pumps out 3 sodium ions out of cells while taking in 2 potassium ions. If you increase potassium on the outside, you'd shift the balance towards more sodium leaving cells, and in the big picture, leaving the blood and body. But of course it's not so simple, and altering the Na-K pump has heavy functional implications too that affect blood pressure in more complex mechanisms.\n\nSo TL;DR: we are becoming increasingly more certain potassium lowers blood pressure, but we're not sure how. It's unlikely to be a simple osmotic mechanism but rather a multi faceted functional one that involves direct and indirect effects."
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1ri1fo | intentional grounding in the nfl | Sometimes they call it, sometimes they don't. What is the deal? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ri1fo/eli5_intentional_grounding_in_the_nfl/ | {
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"You can probably find a more technical definition elsewhere, but basically, intentional grounding is a penalty committed when a passer (generally the quarterback) throws an incomplete pass to avoid being sacked (tackled behind where the play started). There are specific rules dictating what qualifies as intentional grounding.\n\nFor example, it's not intentional grounding if the incomplete pass was headed towards an eligible receiver. In other words, even if it's really obvious that the QB threw the ball knowing it would bounce or end up out of bounds, it's still legal if there's a receiver nearby. Throwing near an eligible receiver is only required if the QB is in the \"pocket\". The pocket, in ELI5-terms, can be thought of as the part of the field directly behind the linemen or big blockers up front. \n\nIf the QB is outside the pocket (ie. scrambling around the field), he does not have to throw the ball near a receiver. However, the ball has to be thrown beyond the line of scrimmage, further forward than where the ball was snapped. \n\nIf a player is penalized for intentional grounding, the offense moves back either to the location of the throw or 10 yards backward, whichever is longer. There is also a loss of down associated with this penalty, so if you intentionally ground the ball on 1st and 10, it can become 2nd and 20. Also note that although it looks like it should be called, the rules do allow a QB to immediately spike the ball without a penalty to stop the clock. "
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csjpzi | every so often i get the great idea to stay awake 24 hours to reset my sleep schedule. why is it so difficult to accomplish this? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/csjpzi/eli5_every_so_often_i_get_the_great_idea_to_stay/ | {
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"text": [
"Because you need regular sleep. It's the same as if you decided to just stop eating for a week. You'd get hungry regardless of how genuine your desire not to eat."
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j6xru | speakers and headphones? what makes a cone + magnets produce amazing sound? | Also if anyone wants to add how that sound travels through a small wire (ex, headphones)? Fuckin magnets man, how do they work? ( < -- jokes)
Thanks! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/j6xru/eli5_speakers_and_headphones_what_makes_a_cone/ | {
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"If I'm not mistaken, the sound itself doesn't travel through a small wire, but the digital signal that the sound produces does. It's been a while since I've read into this, but IIRC: the signal goes from the source (CD Player, PC, iPod, etc) through the wire into the headphone, which has a large coil around a cone, and the cone has a magnet on the back. The copper coil around the cone makes the magnet vibrate with the frequencies it gets from the source, and as the magnet vibrates it moves the cone, which creates the sound.\n\nThat's right, right?",
"The sound is represented by a wave of electricity that has varying voltages when it is being carried over the wire to your headphones/speakers. The cone + magnets turn that electricity into sound waves. Also, when electricity passes through a wire, it creates a magnetic field. The more electricity, the stronger the magnetic field. When the electricity is at its highest voltage, the cone is pulled back the most because of the electricity flowing through a wire around the magnet attached to the cone. When the electricity is at 0 volts, the cone isn't moved at all. For huge speakers like ones at concerts, you have much bigger cables because more electricity needs to travel through them to make the sound louder and move bigger cones. If you change the voltage flowing through the wire fast enough, the cone vibrates and produces sound waves that your ears listen to. Was this a good explanation? I can try to elaborate if you want.",
"If I'm not mistaken, the sound itself doesn't travel through a small wire, but the digital signal that the sound produces does. It's been a while since I've read into this, but IIRC: the signal goes from the source (CD Player, PC, iPod, etc) through the wire into the headphone, which has a large coil around a cone, and the cone has a magnet on the back. The copper coil around the cone makes the magnet vibrate with the frequencies it gets from the source, and as the magnet vibrates it moves the cone, which creates the sound.\n\nThat's right, right?",
"The sound is represented by a wave of electricity that has varying voltages when it is being carried over the wire to your headphones/speakers. The cone + magnets turn that electricity into sound waves. Also, when electricity passes through a wire, it creates a magnetic field. The more electricity, the stronger the magnetic field. When the electricity is at its highest voltage, the cone is pulled back the most because of the electricity flowing through a wire around the magnet attached to the cone. When the electricity is at 0 volts, the cone isn't moved at all. For huge speakers like ones at concerts, you have much bigger cables because more electricity needs to travel through them to make the sound louder and move bigger cones. If you change the voltage flowing through the wire fast enough, the cone vibrates and produces sound waves that your ears listen to. Was this a good explanation? I can try to elaborate if you want."
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a5i1lw | how were maths formulae like pythagoras and area of a circle discovered millenia ago - way before people had access to pens, papers, rulers, calculators, computers, a standard maths education etc? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a5i1lw/eli5_how_were_maths_formulae_like_pythagoras_and/ | {
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"We did have some of those things (writing utensils and something to write on) otherwise we wouldn't know that they discovered it in the first place. They also had math education; that's how this stuff was passed on and able to develop.\n\nThe only thing they were really missing were calculators and computers, which don't discover or prove math anyway. They're just good at doing lots of calculations really fast and accurately. Mathematical discovers and proofs are discovered in the same place now as they were then: in the minds of mathematicians.\n\nGranted, it may have taken longer, with more mistakes or less accuracy. And there are some concepts which involves such complex calculations that computers are required today, but the stuff you're talking about didn't. Just time and careful thinking.",
" > How were maths formulae like Pythagoras and area of a circle discovered millenia ago - way before people had access to pens, papers,\n\nPythagoras lived almost 2500 years after the first usage of papyrus as paper so it's not way before paper.\n\nMany ancient scholars also received an education from the scholars before them and would educate their successors. A maths education wasn't wide spread but it wasn't non-existent.\n\nCalculators and computers simply make arithmetic easier, but they were doing algebra not 17 digit multiplication so a basic calculator wouldn't even have helped.\n\nYour history lessons failed you and all your premises are wrong",
"Papyrus would be used or tabulas (wax tablets) that acted as an ancient echa-sketch. Rulers were absolutely around. Maybe not the exact way we have them today but a measuring stick is probably one of the first 100 inventions of man kind. \nBut anyway like all brilliant minds, they would see a pattern or commonality in nature and would use maths to explain it. \nAlso note the ancient world was quite advanced but sadly a lot of their knowledge was lost. ",
"Calculators and computers, sure. Pens? Paper? Rulers? Math education? These things have been around for a very, very long time. Math as a formal language dates all the way back to the ancient Greeks, ~600 BC (and possibly before).\n\nHeck, rulers have been around since at LEAST 4500 years ago, and pens/papers have been around for almost 5000 years. And that's only counting actual pens and papers, not early forms like ink brushes or papyrus or stone carving (which date almost 10000 years ago). \n\nMathematics as a formal education began around the same time as pens/papers, ~3,000 BC. Higher mathematics start somewhere around ~2,000 BC, and deductive mathematics around ~600 BC. \n\nHeck, people were trying to quantify time (a kind of math) around 20,000 years ago, and the Egyptians of 10,000 BC were using multiplication and division quite fluently.\n",
"Most ancient mathematics was not in the form of formulas as we would think of them today. Algebra, equations, etc., are a relatively modern (e.g., medieval and later) development. \n\nMathematics as we know it emerged out of accounting, which is foundational to any complex state. Without some understanding of balances, you can't levy taxes, you can't assess the value of land, you can't keep track of who owes who what, and so on. \n\nSo way before the Pythagoreans, there were people in the very ancient world (e.g., the Ancient Near East) using a sort of \"brute force\" version of the theorem. The Pythagorean theorem is extremely useful for measuring plots of land, for example. They didn't work through it algebraically: they created lists of common Pythagorean ratios (e.g. 3:4:5), and then used those to sort of estimate likely answers to the missing values they had measured. This is sometimes called the \"science of lists\" and is often used to describe how Ancient mathematics worked in many cultures. \n\n(As for what the lists were written on, it varied, but in the Ancient Near East it was mud slates with a stylus. Note that writing itself seems to have evolved out of these accounting practices; the first written records we have, more or less, are receipts.)\n\nAnyway. Even the Pythagoreans did not formulate equations in the same way we do today. They preferred geometric, visual proofs — again, drawn into things like clay. And it is worth noting that what makes the Pythagoreans interesting is that they did not do this for practical reasons: they thought a geometric proof was a glimpse into perfection, and thus into God. They were numerologists (number worshippers). When I teach about them to my students, I like to go through one of the ancient Pythagorean theorem geometric proofs with my students — it _does_ make you feel like you're touching something perfectly logically true (assuming you agree on the key axioms, etc.). It's a neat thing, and you can see how people in a chaotic and tricky world would really value this glimpse into the perfect.\n\nAnyway. The modern versions of algebraic equations, etc., came later. The Pythagoreans and other Ancients would simply write out what the proof was, e.g., \"the square of the hypotenuse is equal to the sum of the squares of the other two sides\" not \"a^2 + b^2 = c^2 \", as we'd probably do it today. This makes reading such proofs pretty tricky if you're used to a modern notation, and it also makes it clear that they weren't factoring equations the way we would approach them today.\n\nThe question about education is a longer and deeper one, and varies a lot depending on what time period and part of the world you are interested in (e.g. China is really different than Ancient Greece), but in short: you don't _need_ a formal educational system to teach people this kind of math, or anything, really. A formal educational system lets you teach _lots_ of people how to do stuff like this, and depending on how your society is structured that may not be desirable or in demand. Someone in the Ancient Near East would more likely than not be an apprentice to someone already experienced in these trades prior to setting off in it themselves, and would learn from them.\n\nYou don't need computers for any of this; computers just make it easier. People did advanced mathematics without computers until relatively recently, and many people _still do_. Ditto calculators. ",
"**Pens and paper:** Whatever you do with a pen and paper you can do by drawing in sand with a stick. You can also use pebbles to count with. The Latin word for \"pebble\" is *calculus*, which is where we get the words \"calculate\" and, of course, \"calculus\".\n\n**Rulers:** You can make straight line with a plumb line (a weight hanging from a string) or a string pulled taut. Rulers for measuring are actually very old technology, dating back [at least 4 & frac12; millennia](_URL_0_).\n\n**Calculators and computers:** Before these came [slide rules](_URL_1_), and before those were log tables and tables of other functions. Basically, someone sat down and calculated lots of logs, square roots, sines, etc, and wrote down the answers in a big book. There are numerous methods for computing all of these functions by hand to any number of decimal places you desire (and some of these are used by calculators and computers).\n\n**Maths education:** This has been around for as long as mathematics, although the only people educated in mathematics were the mathematicians using it. If you wanted to use mathematics for anything more complicated than counting your sheep or tallying up your accounts, you got one of these guys to do the sums for you."
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1w9kes | when i am taking a bath (or in a body of water), why do hundreds of tiny bubbles collect under my arms, legs and bottom? | I love running my hands under my legs and watching the bubbles rise and listening to the sound they make. It's almost like soda carbonation; but what causes this? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1w9kes/when_i_am_taking_a_bath_or_in_a_body_of_water_why/ | {
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"In simple terms water is filled with various gases. Nitrogen, oxygen, etc. \n\nYou and the things on you - are enough to agitate those gases into forming bubbles (salt, things on your skin, excretions, etc). The amount can depend on the temperature of the water and local pressure. It's also why bubbles form in water left in a glass. Same principle.\n\nAlso the composition of the water can play a role.\n\n"
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1r5gjp | why wouldn't the united states adopt an isolationist stance and save themselves billions of dollars by staying out of war zones? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1r5gjp/eli5why_wouldnt_the_united_states_adopt_an/ | {
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"Because the money the US spends on foreign wars does not just disappear. It's funneled into the industries that produce everything needed to wage war - weapons, ammunition, supplies, services... the list is almost infinite. This complex of industries, or the *military-industrial complex* as it is often called, has grown extremely powerful and spends a huge amount of money lobbying for decisions that keep their profits up. Basically, they lobby for more wars, as disgusting as it sounds.\n\nThe then-president Dwight D. Eisenhower warned us about this in his Farewell Address to the Nation on January 17, 1961:\n\n > A vital element in keeping the peace is our military establishment. Our arms must be mighty, ready for instant action, so that no potential aggressor may be tempted to risk his own destruction...\n\n > This conjunction of an immense military establishment and a large arms industry is new in the American experience. The total influence — economic, political, even spiritual — is felt in every city, every statehouse, every office of the federal government. We recognize the imperative need for this development. Yet we must not fail to comprehend its grave implications. Our toil, resources and livelihood are all involved; so is the very structure of our society. In the councils of government, **we must guard against the acquisition of unwarranted influence, whether sought or unsought, by the military–industrial complex**. The potential for the disastrous rise of misplaced power exists, and will persist. We must never let the weight of this combination endanger our liberties or democratic processes. We should take nothing for granted. Only an alert and knowledgeable citizenry can compel the proper meshing of the huge industrial and military machinery of defense with our peaceful methods and goals so that security and liberty may prosper together.\n\n*(emphasis mine)*"
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tb2tt | how do physics and philosophy relate with each other? | Hey Reddit. Please explain to me how physics and philosophy relate - I hear it all the time, and have even read about college courses specifying in this subject. Are there any notable examples of physics that have philosophical implications along with it? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/tb2tt/eli5_how_do_physics_and_philosophy_relate_with/ | {
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"Basically all science began with philosophy. People asking questions about the nature of existence and the world around them. \n\nThe people who began asking questions about the nature of the physical world are what we now call physicists. It grew from simply asking questions to actual experimentation and demonstration of phenomena and the science we know today.\n\nEdit: And as the wealth of knowledge grew, research and experimentation grew and continues to grow into further niches creating further areas of study.\n\nFurther edit: This is also why there is an area of philosophy called metaphysics; meta meaning above, it deals with things beyond the physical world such as reality and existence."
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1cs1u2 | how come we name storms but not other natural phenomena like earthquakes or tornadoes? | À la Tropical Storm X, Winter Storm Y, Hurricane Z.
EDIT: Everyone's responses are essentially reflecting the same idea: that storms last longer and change locations so they receive names… I still find it a touch bizarre that we don't name other occurrences despite the fact they cause problems that can even outlast storms, but I'm not a meteorologist so I have no say. Marked as answered. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1cs1u2/eli5_how_come_we_name_storms_but_not_other/ | {
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"First of all, here's why we name storms.\n\nLet's say we have 2 friends talking about a 3rd friend.\nThe first one says: \"Did you hear that the kid with brown hair, white shirt, white shoes, and a green lunchbox had peanut butter today?\"\n\nThe second one says: \"Did you hear that Ronald had peanut butter today?\"\n\nIt's much easier and quicker to listen to the second kid talking, because we know who he's talking about a lot quicker, and if you see Ronald a lot, using his name is much quicker. So that's why we name storms. But why not earthquakes or tornadoes?\n\nOkay, let's say you're on the sidewalk, looking at cars. See that blue car? In a few seconds it will be gone, and we won't see it again. And that yellow car? If we call it \"Jimmy\", then in a few seconds it will be gone too. If we give names to all the cars, they'll go away too fast. Just like cars, earthquakes and tornadoes only stay around for a short period of time, so we don't have very much time to give them names, and an even shorter time to use those names.\n\nIn short, we name storms but not tornadoes because storms last longer.",
"Tropical storms last for days and impact people over thousands of miles.\n\nEarthquakes and tornadoes last seconds to minutes, and usually only reach a few miles. And there are thousands each year."
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1i6lam | why does dry ground "flood more quickly" than ground that is a little moist? | EDIT: Adding the clarifying question: "Is this a cohesion thing?" | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1i6lam/eli5_why_does_dry_ground_flood_more_quickly_than/ | {
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"Ground that is already moist can already take in more water quickly. \nDry ground has to become moist first, so the water isn't taken up as quickly as with already moist ground. Dry ground can then flood faster, because there is basically a barrier for the water to sit on top of and that barrier isn't there with already moist ground. \nWith dry ground that has this barrier, the water is displaced more quickly horizontally than vertically as it would with moist ground that is already displacing water vertically. \nThis barrier is just the presence of no water already being displaced vertically.",
"Water likes to stick to itself. \n\nWhen the ground is a little wet that means that the water is pulled into the ground. The water that's already in dirt pulls the water farther and farther in so it soaks up the water well. \n\nWhen the ground is dry that means the water runs over the surface. Sure a some of it will fall into small holes, but the water that is still on the surface will pull it back up and keep it from going into really small spaces. Water doesn't like to squeeze into small dry spaces because then it won't be touching other water. As I said at the start water likes to be touching other water. It sticks to itself. "
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3debn0 | how the words for the phonetic alphabet were chosen | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3debn0/eli5_how_the_words_for_the_phonetic_alphabet_were/ | {
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"They all start with the letter they represent and are unique enough to be identified even by a partial word. This means, even when static/connection issues/noise make it impossible to hear everything, the message can get through.\n\n\"..meo ech..delta del...indy...go\"\n\n\"Romeo, echo, delta, delta, india, tango\" aka, REDDIT.\n\nIf, for instance, you had \"Mike\" and \"Ike\", or \"Hotel\" and \"Motel\", confusion would happen easily."
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50xt6e | how does dunking a hot metal in cold liquid make it harder? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/50xt6e/eli5_how_does_dunking_a_hot_metal_in_cold_liquid/ | {
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"Iron and steel can have a variety of different internal structures - the exact nature of the structure you get depends on a few things, but in iron and steel two of the things that have the biggest influence are carbon content and temperature.\n\nCarbon content is a relatively easy one to alter, as it doesn't change significantly as the metal cools, but what can you do if you've got a desirable internal structure that's present only at high temperatures?\n\nYou can quench the metal... that's what. This rapid cooling means that the transition from the desirable structure to less desirable (i.e. softer) structures doesn't happen to the same extent, and so you end up locking in a structure that you'd normally only see at a much higher temperature in a metal that's now at room temperature.",
"It alters the grain structure of the metal, and it makes it more uniform giving more strength. Grain crystals can be reduced in size and packed back together in a way that strengthens the part. The rate of cooling has a big part on this aswell, the quench can be an air cool or oil bath or a water tank. And it is not limited to steel and iron. Heat treatment can be done on any metal."
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3qdr6b | why does it seem like people go to jail longer for drug charges than murder? | I read about people getting like 10 years for drugs, but then murder/man-slaughter/drunk driving related deaths sometimes get out after only about a year. How? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qdr6b/eli5_why_does_it_seem_like_people_go_to_jail/ | {
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"Because when people deal drugs they cost the government agencies profit, with murder it's just one more cadaver. ",
"Large scale possession with intent to sell gets fairly heavy penalties. The federal sentencing guidelines put vehicular manslaughter is at the same level of penalty as intent to sell 500g of cocaine (around $10,000 worth).",
"One of the major factors that determines sentence length is previous criminal history. If you have previously been convicted of crimes, you are much more likely to get a harsher (possibly even maximum) sentence if you commit another crime in the future. People who don't have a criminal record tend to get much more lenient sentences that are closer to the minimum or low-average end.\n\nThis is the primary reason why there are some people (including in the US) who are locked up essentially for life because of a relatively small crime (e.g. theft) while others who committed more serious acts (e.g. manslaughter) may receive less penalizing sentences.\n\nAnother factor that plays a role is intent (and aggravating/mitigating factors). People who end up in situation like drunk-driving leading to manslaughter have (usually) not committed the crime with intent. It's an unfortunate and tragic accident that the individual is still responsible for, but there is an understanding that the drunk driver was not intentionally trying to harm/kill others. This is in contrast to other crimes like drug trafficking where the people involved are knowingly engaging in a criminal act with intent, and they are doing so for profit.\n\nDifferent states also have different rules, guidelines, and precedents for establishing sentence lengths and some states may impose certain minimums or maximums that differ from other states for the same type of crime. Furthermore, the judge is usually granted a fair amount of discretion when it comes to determining an 'appropriate' sentence length based on the circumstances of the crime and some of the factors I mentioned above.\n\nAlso note that it is possible for prison inmates to be released early on parole if they show good behavior and a willingness to rehabilitate while they are locked up. People who get involved in prison gangs or are otherwise violent, disrespectful to correctional officers, or unwilling to take steps to better themselves are less likely to be granted early release.\n\n\n",
"Because drug dealers aren't generally paying taxes on their earnings. All governments hate not getting money that is 'theirs'.",
"please link me to where a person convicted of murder was released after only a year. not including a judge over turning a conviction. man slaughter is an extremely broad term, and can include self defense which is why they have a low minimum sentence. ",
"Usually when people get charged with serious drug crimes there will be other charges to go along with it and there will be multiple cases as well. Those can add up to huge sentences. "
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s4lj3 | okay, i know fighting zombies is kind of a fun concept. but how to explain the incessant rash of zombie-related everything that struck america in the past few years? | Seriously. Without looking anything up, I came up with Shaun of the Dead, 28 Days Later, 28 Weeks Later, Romero's Dawn of the Dead, Romero's Land of the Dead, Zombieland, Resident Evil 1-5, publication of the popular Zombie Survival Guide, The Walking Dead graphic novels and now TV series...
What the undead fuck. Sure, it's cool to think about. But what's our culture's fascination with taking one type of supernatural being (be it aliens, vampires, zombies, whatever) and just running it into the ground? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/s4lj3/eli5_okay_i_know_fighting_zombies_is_kind_of_a/ | {
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"The cycle tends to go like this, something is obscure and underground. At some point, something comes along to bring at least a part of it out into the light, media companies see an easy way to make a buck. They make it overly romantic, in the literary sense, so that it's easier for a larger audience to digest, people get burnt out, eventually it goes back to being more underground. It happened with wizards, vampires, were-wolfs, the supernatural, it all follows the same path.\n\nThere is, however, another part to the zombie apocalypse in that certain people use it to live out a heroic alter ego in which they are a survivor and will make it through. The humble and meek are transformed into heros and alpha-males overnight. Try to think of the main demo this stuff is aimed at and you'll find your answer. ",
"Err... I'll try to keep this ELI5.\n\nWhen times are bad, people like to entertain themselves with the fantastic, the \"fantasy\" stuff.\n\nSo when times are bad for an entire country, you see more and more movies about superheroes and monsters and other fantasy events.\n\nWith people feeling \"trapped\" by their lack of options, a zombie apocalypse always seems like a great thing to imagine. People suddenly get to be creative, have options, not have to go to work, and have all sorts of fun all while being important... things they can't get in their day-to-day life.\n\nWhen things are good, you see more \"homely\" movies becoming popular.\n\nAs things have gotten worse for America, our movies have moved more towards fantasy because we reject our current reality and want something better.",
"IMO: We like action movies where a shit-ton of people die. We also like to have a clear-cut \"us and them\" kind of story. Zombie movies offer a way to tick both of these boxes without having to use another social or ethnic group. So back in the day, we'd have seen Our Heroic Boys fighting waves of villainous Germans/Japanese People/Russians/Vietnamese/Russians Again/Vaguely-Defined Arabic People. But these days we're a little more socially conscious, and we aren't really enemies with any other countries on such a scale. So now, instead of the \"All-American Soldier blasting waves of foreign enemies\" story, we have the \"Guy who sells TV's blasting waves of undead enemies\" story. (Actually, now that I think of it, the guy from Shaun Of The Dead and the guy from the Dawn Of The Dead remake were both TV salesmen. Hmm.)\n\nAlso, they're a slightly cheaper special effect than werewolves. :)",
"because with a zombie apocalypse you murder your way to safety \n\ni think thats what it is, peoples fascination with violence and inflicting violence. people dont want to kill monsters, they want to kill people but they also want to kill them guilt free\n\nwhat better way then killing zombies? theyre still people but you get to kill them guilt free ... its a win win. \n\nthis is just a guess but i think zombie popularity is in direct correlation to population density. if you live in a area with a shitload of people who act like emotionless zombies around you going to and from work, you probably harbor fantasies of someday killing of all of them ",
"[Something about republicans and democrats...](_URL_0_)"
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6342cc | why can't old people climb stairs | Why is it that most elderly need to use handrails/ canes to get up steps? Is it more linked to the range of motion necessary to lifting a leg that high or is balance the limiting factor, aka is it more decline in the vestibular system versus muscular decline? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6342cc/eli5_why_cant_old_people_climb_stairs/ | {
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"As we age, our bodies tend to break down. Joints can become stiff and arthritic and bones become brittle. Additionally, our coordination and senae of balance can be affected. Walking up the stairs can be very labor intensive and dangerous. A slip and fall can fracture multiple bones and shorten the lifespan of ab elderly person significantly ",
"The elderly often have weak muscles and using a handrail or cane allows an older person to use his/her arms to assist his/her legs.\n\nStairs are actually really hard to climb. You'll notice that no matter how fit you are, you can still become winded from climbing just a few flights of stairs. The amount of strain on your body, in general, is just not handleable by many unassisted elderly people.\n\nAnd if you're asking exactly why stairs are so hard to climb, it's that every step requires you to put all your weight on one leg and have it lift your body to the next step.",
"I've gone from a life where I could run up AND down stairs two steps at a time, often with a tool box or parts in hand, to now using the railing and leaning against the wall, often going from step to step. Bad knees from working on the floor, arthritis and strength is lost as we age. What really sucks is it's also harder to throw the leg over the motorcycle."
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38migp | why do conservatives claim to detest the government's abuse of power but often defend police brutality? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/38migp/eli5_why_do_conservatives_claim_to_detest_the/ | {
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"Republicans tends to heavily favor military. They view police as a local form of military. \n\nThe real reason is this: Liberals think the system is flawed, which conservatives think that people are flawed. "
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fv4k4c | why are tears, sweat, and nasal (whatever the right term is) salty? what is the purpose and function? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/fv4k4c/eli5_why_are_tears_sweat_and_nasal_whatever_the/ | {
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"The saltiness is how the body extrudes the water. Cells can't actively move water by themselves - they have to kind of *persuade* the water to move by itself. Water loves salt. But water is also socialist - it spreads out by itself so that every water molecule gets the same level of access to salt. So, when a cell wants water to move somewhere, it has to bait it. The cell picks up some of the salt it has inside itself and pushes it out into the sweat gland. Then, the water notices that there's less salt inside the cell but lots of unclaimed salt *outside* the cell, so a big horde of socialist water zombies charge out of the cell and hang out in the sweat gland with all the salt - enough socialist water zombies until each socialist water zombie both inside and outside the cell has equal access to salt. \n\nNow of course, this is all just a clever ruse by the cell - once the water is outside the body, the sun's energy is free to evaporate it. Most of the water will do this, leaving just a kind of sticky, salty sheen on the skin.",
"Some of it at least is antibacterial. A lot of microbes can't flourish very well in salty environments."
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3cs9uq | why does the us government which doesn't have the security to prevent 21.5 million employees from being hacked want to put backdoors into all programs? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3cs9uq/eli5_why_does_the_us_government_which_doesnt_have/ | {
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"The US government is made up of people. Each of those people think they are good people doing good work. They work to protect other good people. They think they are the good guys. They want to defeat all bad guys. They think that encryption back doors will give the bad guys fewer places to hide. They want to beat the bad guys so much that they are willing to give up your privacy. They want to beat the bad guys so much they are willing to destroy the entire concept of privacy in order to win against all bad guys everywhere. \n\nThey don't understand that the \"back door\" they want to build can be found by the bad guys. \n\nThey believe that their safety is more important than your privacy.",
"They are to some extent incompetent and don't fully understand the interconnectedness of the digital age.\n\n\"DVD Jon\" is a good example of this. One guy learns how to decrypt DVDs, and within a week everyone in the world can now watch DVDs.\n\nThe \"backdoor \" idea is similarly flawed. The intelligence and legal agencies are still thinking in terms of \"controlling\" information, like back in the 80's: We will keep \"master\" keys for every device, very carefully, and not let anyone else see them, and this will work! But it will only take ONE guy to discover the backdoor (Like DVD Jon) or leak it (Like Snowden) and suddenly everyone in the US will have devices with known backdoors in them. Not too big a deal for many people, but for people in the military, or intelligence agencies, or science/research, or government, or big companies competing against overseas firms, or the financial industry, or many other things... it would be a disaster. And understand it's not that it MIGHT happen, it WILL happen, and once it does, it will be worldwide within 24 hours. And the people with the most insecure devices on the planet will be .... Americans. All in the name of security. They want to build fatal flaws in your devices, so they can access them when they want to without a warrant. And this would only be safe if not a single bad guy in the world ever discovers the backdoors and how to use them. Hell, there are bad guys already in the law and intelligence agencies.\n\nAnyone who grew up in the digital age knows this is a stupid idea. The fact that your government/intelligence/law agencies don't shows that they are comprised of people who are too old to be in charge. They don't really \"get\" the internet or modern media, and they are a danger to you. New, younger blood is needed. Obama, please do a \"refresh\" on them!\n",
"First of all, ODM security was a private contract. Why all of that information was on an open network is a great question, but the government itself isn't necessarily directly to blame. This was also not a \"backdoor\" hack, per say. More like a \"we forgot to lock the front door\" hack.\n\nSOME people making laws may want to put \"backdoors\" into programs/hardware, but these same people have no idea what that entails, why it doesn't necessarily pay off, or how it's done. They are not the ones with technical understanding on the subject.\n\nIn a nutshell, it's not such a simple situation. The people that are actually overseeing technical work are not the same ones that you hear about encouraging implementation of \"backdoors\". There is much debate internal to the Govt as to which approaches should be taken on these topics.\n\nEDIT for clear answer: It doesn't, necessarily.",
"There's two sides to it. What they think, and how they speak.\n\nThe people who want to put backdoors in aren't the politicians talking about terrorism and child abuse. I mean, those politicians *are* advocating removing secure encryption, but the thing is, those ideas didn't originate from them, they barely know what it is and why it's important or else they would have a more level headed stance about it. \n\nSo the question is what made those politicians, who knew so little about encryption to begin with, start on a campaign against it?\n\nWell, it's because they were told some things. But by whom? And why? They were told by intelligence that they had been unable to follow up on terror plots and couldn't stop the spread of child pornography because these people used an system that made them immune to law enforcement. \n\nThese politicians don't know why any good people would want to use a system that makes them immune to law enforcement unless they plan on breaking the law. They understand that people want things to be private, but surely there's a way to do that and just allow law enforcement to have access in. They have been told that they could make back doors into this encryption that only law enforcement could have access to. If we can do this, they feel we should do this. \n\nYou know, in some ways I kind of agree with that. If we could trust our law enforcement, if we could guarantee that this stuff could only be broken with a court order, and that it was otherwise safe, then it does seem quite reasonable. \n\nBut putting aside trust issues, on a technical level I know that there's no way to put in a back door to an encryption algorithm and keep it secure, it simply doesn't make sense. \n\nThe issue is the politicians campaigning on this front have been told it's possible, and don't have the technical background to understand why it's not. They also represent authority, so they trust authority. To the politicians, it's easy. They were told that we can put in a back door that only the good guys can use. They trust their statement that they can do that. They trust that they will act in the best interest of good people. \n\nBut the politicians aren't that important. The real question is why all of a sudden this is a \"threat\"? I'll ignore the terrorism part of it for now, let's talk about the child pornography because current events don't factor into to it the same way. We weren't seeing giant numbers of people being caught distributing child pornography 10 years ago. It wasn't in the news how so many people were getting caught in the distribution of child porn. So why now? Did something change to make that so much more enticing? Is there are big surge in illicit distribution that can't be managed? There weren't tons of people being caught before, and there wasn't a big drop-off of people being caught recently. So why exactly is encryption a big deal when it wasn't, say, 10 years ago?\n\nNow I'll bring back the terrorism angle. ISIS is big, it's scary, and it's RECRUITING people from our countries. We hear about it on the news, but unless we're going to go risk our lives trying to fake recruitment, we don't know how they're doing it. Now intelligence tells us that they make contact by twitter, and then follow up through encrypted channels to negotiate details. Now putting aside the technical details on how exactly law enforcement should be able to break into those conversations, and how effective that could be, lets consider what would happen if laws were passed making encryption breakable by intelligence. If the terrorists were actually using that as a recruitment technique, they could use a system that was not controlled by the law. That wouldn't be hard really at all. They can't make encryption impossible, they can only say that US companies can't sell good encryption, but it doesn't stop someone from writing encryption software that doesn't rely on those companies under US law. \n\nSo why is intelligence pushing for it? It's because it's neither terrorists or child abusers that they're really targeting. It's not every day citizens either, they post everything on facebook anyways. It's business that they want to be able to watch, it's communication with foreign governments that they want to be able to watch, it's minority-report style big data that they want to analyze, it's political opponents that they want to monitor. \n\nWhat the big push is now is that so many sites have gone HTTPS, the whole web has sort of shifted to a more secure model. This is the problem. The problem isn't terrorists, it's that even on this _URL_0_ link, I'm on https, if I go to _URL_1_ it's https. If this were a PM instead of a public post it would be much harder for them to intercept it and analyze it. If I typed in a search on google it would be harder for them to intercept and analyze it. It's not that there's a specific threat, it's that what used to be bright as a light for their own intelligence is now becoming dark. \n\nThink about some of the web based services that are used all over the world. When people do things through facebook for instance, it used to be that those transmissions were being sent plain text, open to interception even when they were private. That was great for people who wanted to eavesdrop on conversations, they got to really like that. But in the last few years, everyone, even small sites, has adopted https as a standard. Now nobody can be eavesdropped on, but they really liked being able to do that. I mean, you get in trouble when you get caught spying on your allies directly, but you want to do it anyways. But you use so many online services every day that, when they were less secure, you end up doing leaking so they don't have to do as much spying. \n\nHowever, now that technology is maturing, we're realizing how people are using it, and making it more secure, and demanding more security. This is important for the industry to really exist in a trustable and usable sense, but it's really annoying for the people that relied on their ability to eavesdrop. \n\nWhen Edward Snowden released data about what was happening, we didn't see a bunch ways to stop terrorism or protect children. We saw how Americans were being monitored en masse, we saw how allies were being watched, we saw that priorities were far more political and power related than safety related. \n\nIt's these people who aren't really the \"government\". I mean you don't really elect the NSA. And even the President can't easily just say \"Ok, you're out. Cool guy, you're in.\" \n\nBut the short answer to your question is that the US government didn't really have the initiative to put backdoors in all the programs. The US government was convinced that it was a good idea by intelligence. The US government is comprised of a lot of non-technical people who are motivated by public opinion, so they were given a story about how they can't keep children safe or keep people safe from terrorism without backdoors, and that they can put in backdoors that would only let good guys in. \n\nThe intelligence authorities aren't focused on keeping children safe, they're focused on strengthening the US's position on the international stage and maintaining their own power as an agency. They don't even really care directly that the government's network was hacked, except for from the threat it presents. Whether backdoors are in or not won't stop future hacks like that anyways, we have strong encryption now, but it was still possible for them to get in. No, they want access to the stuff that's hard for THEM to get into, because their goal is not protection, it's intelligence. And like the terrorists, nothing is going to stop Intelligence from just using secure encryption themselves, because who's going to even know that there's not a backdoor engineered into it? Are they going to get a court order to decrypt something? When has the NSA last gotten a court order to decrypt any of their secrets?",
"The short answer it is to prevent criminals from using encryption to hide the records of their crimes.",
"It's about *power* versus *responsibility*. \n\nPower is the ability to do something. \n\nResponsibility is something you have to do. \n\nEveryone wants power, but none want responsibility. \n\nThe government want the *power* to look into everyone's computers. They do not want the responsibility of keeping data safe.",
"The US Government is not one single entity, it is a system made up of multiple departments serving under multiple branches. The FBI wants a backdoor to encryption programs so that it can retrieve information it requests from search warrants. It's still not clear whether or not that'll be the solution the senate committee thinks is best because that leaves a vulnerability for other hackers to get it, but it's a process atm.",
"The US government at its highest levels is not a meritocracy. People are not appointed upon the basis of the objectively quantifiable skill. If you look to appointees like [Katherine Archuleta](_URL_0_) of OPM, the primary reason she was appointed by President Obama was because she was the National Political Director for his campaign in 2012. \n\nSo instead of her ability to competently serve as a manager of OPM, she was selected upon the basis of her ability to get Barrack Obama re-elected.\n\nWith people like this making decisions for entire departments like OPM, it is no great wonder that most non DOD departments wallow about in a sea of scandal (such as the GSA hot tub motivational conventions in Vegas) and accomplish little.\n\nThe fact that appointments are handed out like spoils to followers without regard to their competence is one of the strongest arguments why centralized federal approaches are usually the worst way to address any problem in the USA. You have hacks like Archuleta in charge.",
"There are a lot of comments talking about backdoors to encryption and trying to make this issue into a conversation about US intelligence and law enforcement policies about data collection and encryption policies.\n\nThat's not what happened with the Office of Personnel Management data breach.\n\nOPM wasn't even encrypting their networks.\n\n_URL_0_\n\nThe CIO at OPM doesn't really understand how things work.\n\n_URL_1_\n\nAnd the General Accounting Office of the US Government identified this issue years ago and was calling for OPM to fix their problem, and the problem wasn't fixed.\n\nIn the end the problem happened because career government employees who don't understand how computer networks and encryption work were promoted to technical oversight positions and they played around with trying to get more funding to fix their issues without actually fixing the issues."
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bk4dip | why do variety packs of food always include the most of the worst flavor? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bk4dip/eli5_why_do_variety_packs_of_food_always_include/ | {
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"Because it's the flavours that people dont usually buy and they have larger stock of it so they try to get rid of it that way"
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1v3w1l | what is platonic idealism? | I keep reading posts all over the internet about it (lately) and I can't seem to wrap my head around it (at all). Please help. I know it has something to do with the theory of forms? but I can't even understand that. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1v3w1l/eli5_what_is_platonic_idealism/ | {
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"Plato was an important philosopher in Ancient Greece. Plato, Socrates and Aristotle are sort of considered the beginnings of Western philosophy so we tend to pay attention to them when studying philosophy.\n\nOne of his philosophies was that thoughts are real. When you look at an apple and think \"apple\", you're working with the abstract concept of \"apple-ness\". This ideal sort of lives in another world of abstract thought stuff and there's only one fundamental \"apple-ness\" that everything apple-like is just a copy of.\n\nAt least that's how I remember it.\n\nBeing a philosopher, there's probably a bunch of other stuff related to it - arguments about the meaning of life, ethics, truth, free will as nd whatnot that stem from this concept.",
"According to Plato, there's the world of ideas (abstract), and the world of shadows of those ideas (concrete). So imagine there is a 'perfect chair' in the world of ideas. When I think of a chair, and you think of a chair, they will both resemble the perfect chairness, but we can't grasp that perfect chair.\n\nPlato's most famous metaphor was this one: a group of people are living in a cave, hands and feet bound, facing the wall. They see the shadows of the outside world on the wall, and that's their only reality. If one of those people were to escape and go outside, he would see the 'real' abstract world of ideas, which is perfect. But if he were to go back to tell his comrades that they should come outside with him because they don't know the real world, they would not believe him.\n\nThis is not limited to objects, according to Plato there were perfect ideas of beauty, virtue, and other kinds of excellence. Plato had a huge influence on Christian ideology, for which this ideal world is heaven, and earth merely the shadow-world."
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d2pzoz | what is the point of three cameras on the new iphone? two makes sense but three seems excessive. what difference does it make? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/d2pzoz/eli5_what_is_the_point_of_three_cameras_on_the/ | {
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"One of the most important aspects of a camera is its size: The bigger the entire thing is, the more light will shine on the sensor, which improves image quality. That is why movie cameras are so incredibly big compared to what normal people might use.\n\nThat is a problem for smartphones: They need to be as thin as possible, but at the same time have great cameras. What they came up with was that they simply use two cameras taking the same image, and then using software to merge those two images. This way, they can effectively double up the size of the camera, without making the phone thick and bulky. This can be done with any number of cameras.\n\nThat's not the only advantage of this though. The cameras can all work with different settings. For example, one can be set up for the bright parts of the image, one for the dark parts, which results in a final image with much better contrast - you might have heard of HDR. Even further, one of the cameras could come without the color filter, making it far more sensitive to light and therefore giving it much better image quality in low-light conditions.\n\nWith three cameras, the iPhone isn't even ahead of the pack: Nokia released a phone with 5 cameras earlier this year."
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6nkj6z | why you can listen to something with only one earbud in and it sounds fine, but if you have both in and a video only plays sound through one, it suddenly is annoying. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6nkj6z/eli5_why_you_can_listen_to_something_with_only/ | {
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"It has to do with your expectations.\n\nWhen you listen to only one, you expect to hear the content only from the one. Even if you miss out on some depth or stereo content, it's what you expect.\n\nWhen you put both in, you expect a richer experience, such as depth and stereo. When it doesn't meet your expectations, you can be disappointed or frustrated or even angry. You might think the content is bad or your equipment is faulty, and this thinking robs you of the experience you wanted."
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9vedfp | why do muscles get sore and damaged from low-intensity exercise? [biology] | From what I understood, your muscles get tiny micro tears from exercising, and this causes the muscle to get sore. Lactic acid doesn't actually damage the muscle or cause pain.
But if someone is doing something with a very low intensity, like walking, standing for a long time, sitting upright for a long time, or lifting very light weights, then why do you still get sore if you do it long enough?
If you hold your arms out in front of you until they start to hurt, and then they're sore the next day, is it because they got small tears just from being held still?
Do muscles actually get little tears just from walking or standing very still? If they're not getting tears, then what else is hurting the muscle? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9vedfp/eli5_why_do_muscles_get_sore_and_damaged_from/ | {
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"I minored in Nutrition and Physical Fitness. Also, a certified personal trainer, and currently a biology major. This is probably the best explain like I'm 5 answer I can give you considering it's a loaded question. Let's talk about what you already know a bit first.\n\n > From what I understood, your muscles get tiny micro tears from exercising, and this causes the muscle to get sore.\n\nMuscles are made up of muscle fibers which are made up of muscle cells. Muscle cells group together to form long fibers that collectively make up the muscle tissue. When a muscle contracts, it's actually the muscle fibers shortening due to the actions of 2 proteins in the muscle cells, myosin and actin, interacting together. As muscle fibers contract to lift something, they are acting against a force. (Usually gravity, such as when picking something up.) This force creates resistance against the muscle fibers, and they break. This is the micro tears you mention. As they break, the brain recruits more. Fun fact. The brain never recruits all of the muscle fibers at once, otherwise the entire muscle could tear off. It only recruits enough to perform the movement. Resistance training does actually stimulate the brain into learning to recruit more. This is called neuromuscular adaptation. The brain still doesn't recruit all of them though. It only recruits more as they tear. The heavier the weight, the more resistance against muscle fibers, and the more they tear. Some still tear however, even with the smallest resistance such as the weight of the limb or body itself.\n\nThink of it like a group of rubber bands, with half of the rubber bands strapped to both one finger and another while the other half hang there. Now if you were to pull one finger away from the other until some of those snapped, and as you did so, each time one snapped you replaced it with one from the half that's not being used, that's basically what the brain is doing when you lift something.\n\n > Lactic acid doesn't actually damage the muscle or cause pain.\n\nIt doesn't. It causes fatigue by trapping carbon dioxide in the muscle which grabs onto oxygen preventing it from being used. This fatigue is what prevents the muscle from contracting any further after the last achievable repetition. This fatigue is actually a safety mechanism, because without it the muscle could keep contracting, until eventually it tore. Resting allows the body to buffer and remove built up lactic acid and carbon dioxide. If you continually did sets though, assuming you ignored any soreness that were to occur, you might eventually cause a muscle tear. This is why in resistance training, typically we stop at 3 sets, unless we're doing hypertrophy which requires we cause more muscle fiber tears and in that case we do as many as 6. Typically there are also more repetitions (a higher volume) with lower intensity (lighter weight) in low intensity training programs, vs fewer repetitions (lower volume) and higher intensity (heavier weight) such as in training programs intended to build more strength. Lower intensity training programs still cause muscle fiber tears though, just not as many and with a different purpose in mind such a stimulating the mitochondria (energy use and production)."
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3qzcip | why does low frequency sound require more power to sound equally loud? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3qzcip/eli5_why_does_low_frequency_sound_require_more/ | {
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"Our hearing sensitivity drops off. To hear really low frequency sound there must be more power used to produce the sound. After a while we feel it in our bones."
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2s9m2n | does "military grade" actually have a standard, or is it just a marketing term? | For example, the commercial for new Ford F-150 stated it is made of "Military grade aluminium." What makes something "Military Grade"?
Edit: Spelled aluminium wrong, was driving me nuts | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2s9m2n/eli5_does_military_grade_actually_have_a_standard/ | {
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"It's a specific type of X (X being whatever the product is, in this case aluminum) is a specific alloy, *Aluminium alloy 7075, 7075-0, 7075-T6, 7075-T651* \n\nFrom Wiki: \n\n > 7000 series alloys such as 7075 are often used in transport applications, including marine, automotive and aviation, due to their high strength-to-density ratio.[2][9] Their strength and light weight is also desirable in other fields. Rock climbing equipment, bicycle components, inlineskating-frames and hang glider airframes are commonly made from 7075 aluminium alloy. Hobby grade RC models commonly use 7075 and 6061 for chassis plates. One interesting use for 7075 is in the manufacture of M16 rifles for the American military. In particular high quality M16 rifle lower and upper receivers as well as extension tubes are typically made from 7075-T6 alloy. Desert Tactical Arms and French armament company PGM use it for their precision rifles. It is also commonly used in shafts for lacrosse sticks, such as the STX sabre, and camping knife and fork sets.\n\n > Due to its high strength, low density, thermal properties and its ability to be highly polished, 7075 is widely used in mold tool manufacture. This alloy has been further refined into other 7000 series alloys for this application, namely 7050 and 7020.",
"It's marketing .. The correct term for components designed to military specifications is 'milspec' .. And there are standards. Milspec chips can handle a higher temperature range than consumer ones. \nUsing 'Military Grade' means they can imply some sort of connection to the military without actually complying with a formal spec. ",
"Also, the military has a detailed spec for *everything*. There's probably a detailed MIL-STD for the aluminum used for cafeteria trays. You could make a truck out of that, and it would be \"military grade\" enough for advertising's sake, but not necessarily a good truck.",
"USAF Aircraft Metals Technologist here.\n\nMy job requires extensive training in metallurgy and aluminium is the most commonly used metal on our aircraft. \"Military grade aluminium\" is a very broad statement considering the number of applications for aluminium in the military. Do not assume it means high quality. \n\nIn the AF, we use several types of aluminium on C-130 aircraft depending on its function. There is no 'standard' military grade aluminium. However, there are standard aircraft aluminiums: 2024/5052/6061/7075. Each of the first digits in the numbers indicate the main alloying element. On the F-150, if you can find the type of \"military grade aluminium\" and its function, you then can determine if that adds measurable quality to the truck value.\n\nIn regards to mil-specs, we order our metals through military distribution channels that quality assurance teams inspect to ensure the metal is what it says it is. We use the same aluminiums as every other civilian aviation org. and even if there was military specific aluminiums, you could not make any conclusions based off that statement alone.\n\nTL;TR: \"Military grade aluminium\" does not mean anything without knowing the specific type of aluminum and its application. \n\nEdit: Corrected by u/sniper1rfa on number system description. Thanks!",
"As an engineer in the shipping and marine industry, I can confirm a couple of different answers for this.\n\n1) First, there are various standards (issued by ISO and other organisations that specify grades for different materials, components and tolerances. Without taking a particular example, let's say that \"Grade 0\" standard steel was the worst, and \"Grade 5\" was the best.\n\n(I'm WAY over-simplifying things here, since grades of steel depend on a lot of factors, but let's keep it simple.)\n\n2) Then, various manufacturers and clients around the world order the particular grades of material that they want for their products. A manufacturer of cheap piping might just ask for \"Grade 1\" steel, but an armoured tank manufacturer might specify \"Grade 5\". \n\n3) In order to help manufacturers and suppliers, there are many other specifications that cross-reference other specifications. MilSpec (\"United States Military Standard\") is one of them and there are many more, for cars, aircraft, trains, power stations and other industries. The MilSpec might say, \"Use Grade 4 steel\", but then you have to look up the ISO standard for steel to see what that actually means.\n\nSo... In a slightly roundabout way, you could say that Grade 4 steel is military standard, because it's particularly mentioned in that military specification. It might not be the *best* steel (even the army has to look at costs), but it's the standard steel that's used.\n\nA.\n\n\n",
"Military grade is just a marketing term. Mil specs exist to create interchangeability between manufacturers. So long as an item conforms to a mil spec, it should be exactly like every other item with that spec. So whether shell or bp creates a grease or oil, it will be the same across the board. Bullets, parts, straps. Everything has a mil spec. \n\nJust because something is made to a mil spec doesn't mean it's good. It just means it's interchangeable. Mil spec weapons stuff for instance tends to be machined pretty loose, in comparison to how tight it could be. A lot of times a mil spec just takes an existing industry standard and gives it a new code. All common metals have existing common naming standards for alloys. Mil specs take those and give me new mil spec codes, which just encapsulates pre existing standards. 2024 aluminum surely has some kinda weird mil number, but it's still just 2024. ",
"Military Specifications or MIL-SPECs are designed standards the department of defense sets up to streamline procurement of resources. \n\nLets take Jet Engine oil for example. There are hundreds, possibly thousands of companies that can formulate an engine oil for jet engines. Each company is going to call their formulations a different brand name, market it with different techniques, and employ different testing methods to establish its properties. Its a nightmare for the military when its trying to buy a product. A MIL-SPEC is a way for the military to define the minimum properties that something must have to do a specific job. For jet engine oil, some of those properties might be Viscosity, operating temperature, density, oil life, ect. The military establishes the MIL SPEC for the oil and it basically makes a box that products must fit into in order to be considered for procurement.\n\nFor something like aluminum, the alloy that Ford is using probably has properties that meet a MILSPEC. This does not make the alloy special in any way, it simply means that its properties match those that the military defined on a piece of paper for one of their uses. \n\nMILSPECS can be looked up at [this website](_URL_0_) if you are curious about them.",
"It means materials were provided by the lowest bidder.",
"In the case of the aluminun on the trucks that you specifically asked about, it's just a marketing term. So the Ford trucks use a similiar alloy and treatment type as some military applications, so they just spam that word as a marketing term. \n\nHowever, in some cases, there is a standardized set of military specifications for some things that actually have a real meaning. A good example is electronics. \"Ruggedized\" computers such as the Panasonic Toughbook and phone devices are rated by an IP code that spells out exact tests and qualifications that allow it to be used and stamped as such.\n\n_URL_0_",
"Marketing. Just like \"aircraft grade aluminum\" is marketing. If it's made from the same tin crap used in airplane ashtrays, it's aircraft grade.",
"Without knowing the military specification, it's kind of moot. \n\nFor instance, ballistic glasses/goggles. The U.S. military standard requires that ballistic eyewear must be able to withstand up to a .15 caliber (at 640 ft/sec) for spectacles and .22 caliber at 550-560 ft/sec for goggles.\n\nA lot of \"military grade\" stuff is just marketing. ",
"I've served for 8 years and 'military spec' equipment is certainly not necessarily \"better\" than commercial equivalents in any way. It just means it meets the requirements we listed, which can be pretty low or irrelevant to civilians.",
"Mechanical Engineer that worked in Aerospace here.\n\nA little late in the game, as you've already heard the comments about marketing. But I'll throw in my two cents to add some perspective.\n\nAs a design engineer, I have to specify materials to be used in a given design quite often. Engineering conditions, cost, material availability factor into the end decision. The easiest and most cost effective thing to do is to spec something whose material spec is widely available. Typically, material specs are given by an engineering society or organization like ASTM, ASM International, or ISO. Aerospace, military, and just about any engineering firm uses these specs often because their properties are known, predictable, tested, widely available, standardized, certifiable, and traceable. The military will sometimes develop their own spec because they can have unique engineering requirements (jets and tanks for example). The spec is usually public knowledge because it needs to be available for private engineering contractors to reference.\n\nThere's a huge process involved in getting a new material/alloy spec'd into the books that requires a huge amount of overhead cost; so unless the engineering application is **very** specific, you will use an off-the-shelf ASTM, ASM, or ISO spec material. 6061 aluminum is a good example: cheap, machinable, good material properties, and weldable. It's a good all round material, so many engineers like it - Aerospace included. Therefore it could be called \"aerospace grade\" but is about the cheapest billet material you could get.\n\nJust about anybody can buy this material. If you go to a scrap yard, 99% of the aluminum there would be, to some degree, \"aircraft grade\" or \"military grade\" depending on its previous application.\n\nIn the case of the F-150, that aluminum is probably just some standardized aluminum just about any joe-blow engineer can spec and buy. I guess the \"military grade\" somehow builds some intrinsic value into it, but it says nothing about the material spec, its yield strength, tensile strength, or stiffness - the properties you *actually* should care about. But this is over most people's heads, so they just resort to a simple name that builds intrinsic value.\n\n*Edit* Furthermore, in the engineering world, nobody ever says \"aircraft grade\" or \"military grade\" materials. You will never see these terms anywhere in any drawing or blueprint. We spec the material standard by organization/society and respective alloy number.\n\n*Edit 2* I meant to say the previous statement in reference to structural materials only. Electronics are different as pointed out by /u/theqmann",
"As to your edit, the Ford F-150 is an American made car and so the element is spelled aluminum not aluminium. We Americans went with the spelling that the British scientist who invented the refining method preferred for the element rather than the one the journal that printed the discovery chose. "
]
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| []
| [
[],
[],
[],
[],
[],
[],
[
"http://everyspec.com/"
],
[],
[
"http://www.androidpolice.com/2013/07/01/ingress-protection-and-us-mil-810g-explained-what-these-ratings-really-tell-you-about-a-smartphones-toughness/"
],
[],
[],
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|
9xos0r | the new si base base units | Wikipedia wasn't much of help here. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9xos0r/eli5_the_new_si_base_base_units/ | {
"a_id": [
"e9tw9tr"
],
"score": [
8
],
"text": [
"Basically, the kilogram was redefined and the reason for this is because the standard for the kilogram was a metal cylinder in the basement of some building in Paris. Scientists wanted to remove the need for a physical object, so they redefined the kilogram in terms of the physical constants of nature, mainly Planck's Constant, h. They did this by very precisely measuring h, setting the value for it and redefining the kilogram, Kelvin, the mole, etc in terms of this newly precised constant. \n\nThis removes the use of the physical object as a standard, and also physical objects can degrade and lose some mass over time. But redefined them in terms of physical constants, this won't be an issue. "
]
} | []
| []
| [
[]
]
|
|
a36lnn | how does a secret recipe stay secret? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/a36lnn/eli5_how_does_a_secret_recipe_stay_secret/ | {
"a_id": [
"eb3rx4w",
"eb3ry8j"
],
"score": [
2,
5
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"text": [
"They probably make all those with access sign a non disclosure agreement.\n\nDr pepper classifies its formula as a trade secret kept in 2 separate parts - you can maintain this by have having two facilities, that combine the ingredients that furret have access to then send them to a third factory that combines the two halves and bottles it.\n\nBut you could just use legal threats against the few workers that know what they are pouring into the vats, and at what quantities. ",
"Each person can only be responsible for part of the mixture, for one thing. If I mix the first few ingredients, and then someone else is in charge of boiling it for whatever amount of time, and then some other person is adding extra ingredients, and so on, then none of us knows the whole recipe. Coca-cola has a process like this going on at a much larger scale, between several different factories. And I'm sure that the people who mix up the first few ingredients are required by agreement not to disclose their part of the recipe to others. "
]
} | []
| []
| [
[],
[]
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|
||
clqxx2 | what exactly is glass? how is it clear? could you 3d print glass? | Is glass a naturally occuring thing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/clqxx2/eli5_what_exactly_is_glass_how_is_it_clear_could/ | {
"a_id": [
"evx8r9w",
"evx9g2z"
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"score": [
34,
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"text": [
"Glass is typically comprised mainly of silica sand, which is just ground or otherwise broken down quartz crystals.\n\nQuartz itself is clear, and when you see a large piece of quartz, and cloudiness is either from impurities or flaws in the crystal structure that refract light making it appear less transparent.\n\nTheoretically you could 3D print with glass, but it would be a pretty specialized printer that you would need. It would have to melt the materials, close to 3000°F, and then it would have to maintain a high temperature for all of the glass you've already printed to prevent the glass from cooling too unevenly and cracking. The main problem with the printer would likely be that it would be difficult to support the glass as you print it, it would still be in a liquid state and would try to settle with gravity. This is why glass blowers have to keep their blown objects constantly moving and rotating so that all sides deform as evenly as possible.\n\nAnd finally, yes, [glass can be created in nature](_URL_0_), the only example I am familiar with is when lightning strikes on a sandy area. But, it isn't glass like we think of glass, because it's not all melted evenly, and so it's usually more like a fused chunk of sand than a glass window pane.",
"Others have pointed out how glass is made, but maybe I can help with the rest of your question. Glass is something called an \"amorphous solid,\" that sounds complex, but isn't. If you take a sheet of stainless steel, and look at it under an electron microscope you'd see that the atoms are arranged in a fairly regular crystal lattice. Because of the way that a material like that is structured, and because of its electronic properties (as in, how the electrons in it in behave) light will be rapidly absorbed or reflect near the surface. In glass however, there is no such regular order, and the electronic structure is such that light *can* pass through it. \n\nOf course this is not the only kind of substance light can pass through, but I can't think of a way to ELI5 exactly why that is. I can give you an example like ALON (ALuminum OxyNitride), which is a crystalline solid and quite transparent in the wavelengths we use to see. That last bit is the key; it isn't generally transparent the way glass is, it's really just transparent in a broad section of the visible spectrum.\n\nAs for naturally occurring, yes. Glass is routinely formed from volcanic activity; you've heard of Obsidian right? That's volcanic glass. You can also find glass formed when lightning strikes sand of the correct composition, as a result of meteorite/asteroid impacts, etc. \n\nAnd yes, you can 3D print glass, and it has been done before."
]
} | []
| []
| [
[
"https://www.mnn.com/earth-matters/climate-weather/stories/fulgurites-when-lightning-strikes-sand-magic-is-formed"
],
[]
]
|
|
3bex6x | why are disc brakes more effective than drum brakes? | As far as I know they work using the same principle, calipers pressing against a surface linked to the wheel to slow it down, just disc brakes compress against a disc and drum brakes expand out on a drum. Why is it usually more efficient to use disc brakes if the technology is the same? Shouldn't they both be equally as effective? This is of course ignoring the fact that disc brakes are easier to service, which is an advantage on its own. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3bex6x/eli5_why_are_disc_brakes_more_effective_than_drum/ | {
"a_id": [
"csll3xs"
],
"score": [
3
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"text": [
"I agree with MsDosNerd that disc brakes have better performance due to superior heat dissipation I would point out that drum brakes also have friction material that wears out, just like brake pads. In this picture: _URL_1_ the grey material is the brake lining, when the brakes are applied it gets pushed against the inside of the drums and provides the braking effect. That material will wear like a brake pad on a disc setup, maybe not at the same rate but it will wear out. Here is a pic of some rather worn out shoes (black) vs new ones (grey). You can see how much of the old ones has worn away: _URL_0_\n\nI'd also add that another reason that disc brakes have become popular is they are reasonably easy to make - discs are cast and machined on mass, the caliper is also usually cast and just needed a few seals to go around the piston(s). \n\nIn a drum set up you need the shoes, return springs, securing pins, self adjuster, the drum, backing plate, slave cylinder - lots more bits, more difficult to assemble. Its easier and cheaper to produce disc setups. here is a typical drum setup, lots of bits in there ! _URL_2_\n"
]
} | []
| []
| [
[
"http://members.rennlist.com/pirtle/svc_br6.jpg",
"https://upload.wikimedia.org/wikipedia/commons/e/ef/Brake_shoes.jpg",
"http://www.renault4.co.uk/rear-brakes/girling-brakes.jpg"
]
]
|
|
41yugy | why can't solar panels on a home provide energy without connecting to the public energy grid? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/41yugy/eli5_why_cant_solar_panels_on_a_home_provide/ | {
"a_id": [
"cz69ub8",
"cz6b26r"
],
"score": [
5,
2
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"text": [
"Well they totally can, but it requires batteries. It's also more work and there isn't a benefit unless you're totally off the grid. \n\nThe other big benefit of tying in to the grid with solar is that you can sell excess electricity in some states /provinces and potentially, even at peak rates.",
"You don't have to grid tie, at all. In fact, you can convert most of your house to DC and only use an inverter for your furnace, A/C, stove, water heater, etc. If you truly want to be \"off grid\" - you'd need to start replacing the higher draw stuff with alternatives - a clothes line, for instance. A pellet or rocket heater instead of an electric furnace. Propane for cooking during the winter, or using cured, canned, or frozen foods. BBQ, slow cookers, pressure cookers, etc for meals in general to move away from needing an electric oven. Planting trees to provide shade for your house in the summer, and using large fans to pull air from the cool side to the warm side, and so on.\n\nEven barring the initial cost of solar, all of these changes take planning and serious lifestyle adjustments."
]
} | []
| []
| [
[],
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|
3eqzrv | why do people like avoiding studying? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3eqzrv/eli5_why_do_people_like_avoiding_studying/ | {
"a_id": [
"cthkfgi"
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"score": [
5
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"text": [
"People inherently love studying. The thing is, when you are in school, you create this kind of mental block where you force yourself to think that studying is somehow bad and you start procastonating. But when you learn somethong new in the real world, you usually love the fact that you gained knowledge."
]
} | []
| []
| [
[]
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|
||
sqeex | inflation and hyperinflation | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/sqeex/eli5inflation_and_hyperinflation/ | {
"a_id": [
"c4g42mz",
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"text": [
"Good explanation here:\n_URL_0_",
"Elpez's link provides some good explanations of inflation, so I'll let you have a look at that. Really, it's not so hard to understand: when you make more bills, each one is worth less compared to goods if the goods aren't increasing in quantity too.\n\nIt doesn't address *hyperinflation* however, which is a related but not identical phenomenon. So let's talk about that.\n\nGoing with the Pokemon card example cause I think it's good. I'm going to try to make this numerical AND ELI5, so follow along. You and your friends collect Pokemon cards. There are Charizard cards and there are Diglett cards (the metaphor here is that Diglett cards are like money and Charizard cards are like goods, but, don't worry too much about that until after you read this through). Right now, between you and all of your friends, there are ten Charizard cards and 100 Diglett cards. You don't own any of the Charizard cards, and you own 1 Diglett card. \n\nYou're a greedy little kid though, and you want some Charizard cards. Right now, understanding the market as they do, your friends are willing to trade 1 Charizard card for 10 Diglett cards—a little too rich for your blood. But you come up with a plan. See, your Dad owns a very high quality copy machine for his business, and you realize that it's possible for you to make an exactly perfect replica of a Diglett card for free (your Dad doesn't know you're using his copy machine, and he keeps paying for the ink and paper. Also, you can't make a Charizard cause of the foil). So one night you sneak into his office and print out 10 Diglett cards, which you intend to use to buy your friend Billy's Charizard card.\n\nThe next day goes smoothly. Billy happily sells you his Charizard in exchange for the 10 Digletts you printed since that's the going rate, and you go home a richer boy than you left.\n\nThat night you print out ten more Digletts, which you'll bring to Bobby to buy *his* Charizard.\n\nYou meet Bobby the next morning in a Dark alley, Diglett cards in pocket, salivating wildly in anticipation. \n\n\"Do you have the card?\"\n\n\"Yeah, I got the card. I got the card right here,\" he replies, gesturing towards his backpack.\n\n\"Well what are you waiting for? Let's see it!\" you insist.\n\n\"Not so fast, arup02! How much you gonna pay for this here Charizard card?\"\n\n\"Why, ten Diglett cards, of course. The going rate.\"\n\n\"Well here's the thing about that, arup02. I've been paying pretty close attention to the market, what with these reports I've been buying, and something seems weird. By my count, there's at least 110 Diglett cards in circulation—and just yesterday there was only 100.\"\n\nYou start to sweat a little bit. You didn't think anyone would notice the increase in the supply of Digletts, but Billy is proving to be a little savvier than you had imagined.\n\n\"Well, how much you want for it then?\" you ask.\n\n\"Well, I guess I could part with it for 12.\"\n\n\"12?! Why 12? There are 110 Diglett cards in circulation and 10 Charizard cards! 110/10 is 11 so surely you don't want more than *that* for it!\"\n\n\"These are uncertain times, arup02. Yesterday there was a stable supply of 100 Digletts. Today there's 110. Who knows what there'll be tomorrow? 120? 140? I need a little extra if you're going to ask me to take on this risky Diglett card.\"\n\n\"Fine,\" you sigh. You let him know that you'll need to go home to get the rest, and arrange to meet up a little later. When you get home you print out two more Digletts, meet him back in the alley, and go home with your prized second Charizard card.\n\nThat night you get to thinking. It seems like, every time you buy a Charizard card, the Diglett supply increases *because of you*. That means each time you buy a Charizard card, it'll be more expensive than the last. But there remain 8 Charizard cards out there, and you gotta catch 'em all, so what choice to you have? You print out 20 more Digletts (just to be safe), and the next morning to set off to Sally's house, a big time collector who holds a massive collection.\n\n\"So, 12 Digletts, right?\", you ask Sally, who is lounging next to the pool behind her giant Spanish mansion. \"That's how much I paid Billy for his just yesterday\".\n\n\"I'm not sure I can accept Digletts anymore. I've noticed that the supply of Digletts is *increasing at an increasing rate*. Only two days ago, the supply was 100. Then yesterday it was 110. Now it's up to 122. My forecasters tell me it should be up to 136 tomorrow. Pretty soon they'll be worthless. Do you have any Pidgeys? Those seem like they may be safer to hold in the near future.\"\n\n\"I don't deal in Pidgeys,\" you reply. \"Only Digletts. But how much do you want? I've got loads.\" You know that if she asks for more than you have on you, you can always go home, print some more, and bring them back tomorrow.\n\n\"I'd be willing to part for it for 15—14 because that's what I forecast them to be worth, and then an extra to compensate me for my risk if my forecasters are wrong,\" she says, gesturing towards the east wing of her mansion where you catch a small glimpse through the window several rows of men in suits, yelling into bluetooth headsets and typing furiously into DOS-esque computer terminals.\n\nYou cough up the 15 and head home.\n\nEach time you buy a Charizard, you make all the rest of them more expensive by increasing the Diglett supply. No matter to you though. You just keep printing and buying and printing and buying. By your fifth card, the price has shot up to over 25 Digletts (2.5 times what they cost a week ago), and you've personally printed over 150 Diglett cards since you started this. Each Charizard card costs exponentially more than the last. You've got your Dad's printer working overdrive, and you're spending almost *all your time* doing nothing but printing Diglett cards.\n\nMeanwhile, your friends are all going through absolute hell. See, they're not all so interested in buying Charizard cards, but they use Diglett cards for all kinds of other things too. Billy, for instance, does Sally's math homework at recess every day in exchange for 5 Digletts. He would trade the five Digletts to Bobby for his Fruit Roll Up at lunch, who would typically use those Digletts to buy Pokemon Card forecasts from Sally. That was working perfectly up until a week ago, when Digletts started to drop in value. Sally noticed first, and she increased the price of her reports, which meant Bobby couldn't afford the reports unless he started demanding more for his Fruit Roll Ups. That would mean Billy wouldn't be able to afford Fruit Roll Ups unless he got a raise from Sally, but savvy business woman that she was, Sally had Billy locked into a contract that kept his wage frozen until next week. Billy had to cut his Fruit Roll Up consumption down to one every three recesses, which really hurt Bobby's bottom line. He had to end his business relationship with Sally, and being her biggest account, Sally had to lay some people off, starting with Billy. Commerce on the playground ground to a halt as everyone was scared to accept Digletts for anything, since everyone knew that tomorrow they would be worth a fraction of what they are worth today.\n\nBut you don't care. You know you're the very best, like no one ever was, and if anyone should own those Charizards, it should be you. The ends, in your eyes, justify the means entirely, and if there are casualties along the way, well, that's just the way it's gotta be. Besides, you only need to buy five more Charizards, and then you'll stop printing Digletts altogether (of course, this will more than double the Diglett supply).\n\n\n\nHyperinflation happens when governments finance their *spending* entirely (or mostly, at least) by printing money. Each time the government prints money in order to buy something (a tank), it increases the money supply without increasing the supply of goods and services, devaluing the money relative to the goods. Then, next time they want to buy a tank, a tank costs a little bit more. By the time they've printed money to buy a whole bunch of tanks, the money supply has shot up exponentially, and with it the price level, as the price level makes tanks more expensive, making the government have to print more money to buy the tank, making the next tank more expensive, and so on."
]
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[
"http://www.reddit.com/r/explainlikeimfive/comments/j9vgc/eli5_inflation/"
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||
1ynu5i | why does every reality show now appear to be scripted? are there currently any that are truly unscripted? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1ynu5i/eli5_why_does_every_reality_show_now_appear_to_be/ | {
"a_id": [
"cfm5e53",
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"text": [
"because it's about ratings. not actual reality.\n\ncause real reality would be me for a day... and that'd be boring. not one person is interesting for a while 24hours.",
"Because it would require a lot more filming and money to piece together the interesting parts for many of these shows. It's easier and cheaper to fake it.",
"A real reality TV show: The protest coverage of Ukraine. People would maybe tune in for 5 minutes, then get bored and move on to something else. Reason being, that five minutes they spectated might have absolutely nothing going on but a shifting of lines back and forth.\n\nNow you switch over to a scripted reality TV show that's BALLS TO THE WALL. Constantly shit going on, be it stupid drama between incredibly ugly 45 year old teenagers, basketball players that'll never be All-Stars or rappers nobody's heard of. The content in itself, a complete joke, who the hell are these people? But the viewer wants to be entertained, and this bitch is dragging that bitch around by her hair for five minutes straight, so they settle in with their popcorn and wait to see who goes to jail. \n\nThe people want entertainment, not reality. They'll casually let the world burn as long as American Idol is on TV to distract them. "
]
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[],
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2na4f9 | assume the universe is infinite, is there then other realities in which everything is almost exactly the same as on earth? | For example, EVERYTHING in the past up until now on earth happens the same way, except in this alternate universe, you are eating an apple now as opposed to reading this post without the apple / whatever you are doing now.
EDIT: A lot of people are just telling me the term infinity is boundless are never ending, but not that all possibilities are available e.g rolling a dice 100 times and getting a platypus.
ELI5 again: But when talking about the entire universe / all that is in existence.. aren't we talking about every possibility and the only bounds are the laws of physics whatever they may be.. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2na4f9/eli5_assume_the_universe_is_infinite_is_there/ | {
"a_id": [
"cmbq9yr",
"cmbrfs5"
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"score": [
5,
11
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"text": [
"that's not necessarily true. just because something is infinite does not mean it does anything interesting.\n\ni can come up with an infinite string of numbers that never repeats itself but is entirely bland. 10100100010000100001.... (i.e. add one more 0 between the 1s every time)",
"Relevant Numberphile video:\n_URL_0_\n\nMy understanding is that:\nIn a universe of a Googolplex meters across (much larger than ours, but still smaller than infinity), you could expect to see entire regions of space that are identical. Basically there would be so much space that the space could not be filled without repeating itself. There are only so many possible quantum states. \n\nI would hypothesize that a truly infinite universe would be larger than one of (an unimaginably large) finite size, and you should therefore expect to see the phenomena of which you inquire.\n\nELI5: In an infinite universe, batman is reading a comic about you."
]
} | []
| []
| [
[],
[
"http://youtu.be/8GEebx72-qs?t=4m12s"
]
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2r8l88 | how would nasa describe the location (coordinates) and bearing/range of a spaceship traveling to mars or elsewhere in the solar system? | Oh and speed, relative to what? To earth, Mars, sun? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2r8l88/eli5_how_would_nasa_describe_the_location/ | {
"a_id": [
"cndg6fm"
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"score": [
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"text": [
"\"As any spacecraft moves through space, it is communicating with Earth by sending off radio waves. These radio waves can tell us a spacecraft's speed in two ways. The first one is very simple. Since radio waves (like all other electromagnetic radiation) travel at the speed of light, we can figure out how far away something is by how long it takes for radio waves to travel to it, bounce off and travel back. If the waves take a longer time today than they did yesterday, we know how much farther the ship is, or how much it has traveled in a day. From that we can figure out the speed.\n\nA much more accurate way of telling a ship's speed is by using the Doppler effect. If the craft is moving away from Earth quickly, radio waves from it will get spread out, and if it is traveling towards Earth, radio waves will be scrunched together. How much the waves are spread out or scrunched together depends on its speed. Using the Doppler effect is very precise. It makes it possible for the radio telescopes of the DSN to measure spacecraft speeds to within hundredths of a millimeter per second.\"\n\nSource: _URL_0_\n\n"
]
} | []
| []
| [
[
"http://www.qrg.northwestern.edu/projects/vss/docs/navigation/2-how-tell-speed.html"
]
]
|
|
m5jzd | why is staring at a computer screen more exhausting than staring at a tv screen? | I get tired far quicker from watching something on a computer compared to a TV. Is it just because typically a computer screen is closer? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/m5jzd/eli5_why_is_staring_at_a_computer_screen_more/ | {
"a_id": [
"c2ya7ta",
"c2ya7ta"
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"score": [
3,
3
],
"text": [
"Being closer could cause additional strain on your eyes. A computer is also just less passive. With a tv you're just watching and listening. With a computer you're generally reading. ",
"Being closer could cause additional strain on your eyes. A computer is also just less passive. With a tv you're just watching and listening. With a computer you're generally reading. "
]
} | []
| []
| [
[],
[]
]
|
|
3ghryf | why do some drinks have sodium in them (like gatorade, iced green tea, etc) and what is the difference between sodium and salt? | I am drinking Kirkland brand Diet Green Tea with Citrus right now and it has 0g/mg of anything in it except it has 100mg Sodium. It tastes pretty salty too, so my question is, what is the difference between sodium and salt and why would you want your soft drink to be salty? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3ghryf/eli5_why_do_some_drinks_have_sodium_in_them_like/ | {
"a_id": [
"cty7w0h",
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"text": [
"They have sodium in them because it makes you thirsty and then you buy more of their drink. They have sugar/other sweetener in them to cover the taste of the sodium. They do this on purpose to generate sales because there is no need for that much salt/sodium",
"Salt is actually NaCl (Sodium Chloride). When it dissolves in water it dissociates, meaning the sodium and the chloride separate. As such, a lot of the time when you see sodium as an ingredient that sodium is in the form of salt, but not always. \n\nSodium is important in energy drinks because it helps your body move and use water effectively. When you sweat a lot you lose sodium through your sweat (which is why sweat tastes a bit salty), so energy drinks include sodium to replace this sodium lost. Also it just tastes good. ",
"_URL_0_\n\nSodium is a chemical element, salt is the common name for a molecule containing a sodium atom conbined with a clorene atom. "
]
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| []
| [
[],
[],
[
"http://chemistry.about.com/od/moleculescompounds/a/Sodium-Versus-Salt.htm"
]
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bcx2hb | do other galaxies in the sky move? | Since the Earth spins, the sky appears to rotate around us throughout the year. Our galaxy is also spinning, so do objects beyond our galaxy (other galaxies and nebulae) rotate relative to the stars (in our galaxy) we can see in the sky? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bcx2hb/eli5_do_other_galaxies_in_the_sky_move/ | {
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"Yes, other Galaxies rotate and move.\n\nBut it occurs so slowly relative to us that we can't really notice it.",
"Other galaxies are as \"fixed\" in the sky as the stars are. The galaxies are of course moving -- most of them away from us, and all of them very very fast -- but their movement isn't noticeable within the span of human civilization. The galaxy M31, for instance, is called the Andromeda Galaxy because it's in the constellation Andromeda. It's always been there, in that spot, and always will...moving into the far future, it will be the stars making up the constellation that will drift away before M31 does.\n\nHere's an analogy: put an object in the center of the room and pretend it's the sun. Now walk around the object, pretending you're the Earth. At one point, the \"sun\" will be in front of the door, then later it will be in front of the couch, then the window, then the TV, and so on. Those things in the background are the stars or constellations that the sun moves through over the course of the year (the series of constellations that the sun passes through are called the zodiac). But if there's a window in the room, you are able to see a mountain fifty miles away. That's a galaxy. The mountain is *always* going to be in the window...it won't be \"in\" the couch or the TV.",
"Technically, yes, but the distances involved in the universe are so mind-bogglingly huge, things moving at millions of miles per hour won't have perceptibly moved through the entirety of human experience. Space is REALLY REALLY BIG."
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357s6l | all of a sudden, the famous video of "leeroy jenkins" has become distorted. how does this happen to a video that (i assume) hasn't been tampered with and has been fine for years? | Or maybe it's been happening for a while, progressively getting more and more distorted to the point where it's noticeable? I wonder if the whole video will eventually will become a mess of jumbled noise? Still confused how it could happen in the first place. Thanks!
_URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/357s6l/eli5_all_of_a_sudden_the_famous_video_of_leeroy/ | {
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"I haven't watched this in years. But god, its the same video on the same channel. Youtube must have kept this on an ancient server.",
"Considering the age of the video, it's likely that it was converted to a more current format by Youtube\n\nBasically, video is stored with compression that reduces the size, there are many methods to compress a video, and some of them are proprietary\n\nWhen you convert video from one format to another, you have to decompress it and re compress it in the new format. the fastest compression methods use 'lossy' algorithms, which means that the video doesn't save all information, just enough to more or less reproduce the original.\n\nWhen you change the format, you end up having the losses from the original compression, and introducing more losses with the new compression.\n\nWhat you see in the linked video is likely from that (it's a similar look to a Jpeg image that has been edited and re-saved multiple times)",
"This one is better.. probably did not go through multiple conversions. \n_URL_0_\n",
"But I'm confused. [There is a link for the high res version](_URL_0_) when I go to the link OP provided. ",
"My take on it is that it's similar to taking a photocopy of an image, then you photocopy the resulting photocopy of the original image. Do this enough times to each resulting photocopy, and the end result gets messier and messier each time.\n\nYouTube automatically compresses the videos that get uploaded to them, and for each time YouTube changes file formats, these already compressed videos get compressed even more. In particular, these old ones were uploaded during the time when dynamically adjusting quality was never a thing, so the only way for its quality to go is down.",
"When Air Force Pararescue Jumpers are called in Afghanistan the loudspeakers blare \"LEEEROOYY JENNKINNSSSS\" and they all start sprinting to the blackhawk helicopters. It's the official sound that plays to summon them from rest/etc.",
"Hahaha oh god its so bad. He runs in and its just \"......OOH-\"\n\n*ten seconds later*\n\n\"BZHHH BZZCHCHBH BZXZZBHBH!??\"\n\n\n",
"That isn't just a rad techno song? Who'd have thunk?",
"I am watching this post as an interesting test of the power of Reddit. How long before a nerd fellow traveller at Google sees this post and fixes the YouTube video?",
"Automated transcoding by servers to adhere to new codecs which are optimized to cut down bandwidth costs and deliver a seamless streaming experience. ",
"This is very sad to see; hopefully YouTube notices it now and restores it from a backup. But on the bright side we still have chicken.",
"There is some poetic beauty to this, with our internet cultural content slowly fading out of view, becoming archaeological mysteries for future internet archivists to discover and mystify about. At the current rate of new memes, videos and internet services appearing and disappearing it will be impossible to maintain everything anyway, so perhaps it's for the best that older stuff makes way for new generations. ",
"Wasn't it established some time ago that YouTube basically uses ffmpeg and mplayer based software to transcode things all the time? So that would be a good starting point. ",
"Here is a version of the video in which the audio is fine.\n_URL_0_",
"Conversion stuck at 240p quality. Audio was originally bad, so that's already best at 240p. The uploader should contact YouTube to re-encode the video at its original 1080p."
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66tnl5 | how are traffic light sequences decided and programmed? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66tnl5/eli5_how_are_traffic_light_sequences_decided_and/ | {
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"The sequence is usually the same, north/south goes, then people turning left, then east/west goes, then more people turning left. At a good intersection the length of the light is determined by inductive sensors buried in the road, which senses the cars and know exactly when the last one goes through.",
"My amateur understanding is that in many towns the traffic patterns are monitored and adjusted according to time of day for what makes the most efficient and safe traffic patterns. \n\nWe are so controlled ¯\\_(ツ)_/¯\n\nThey will either be on a timer pattern where each light changes according to a predetermined and controllable sequence (how long each light is green, orange, or red. They may also be on a sensor based system where the priority will be longer greens for busier streets while sensors within the pavement (or cameras, infrared, laser, I'm not confident about how, I just know there are sensors.) that start a countdown for the light to change. These sensors can also be buttons that pedestrians can push to gain safe crossing.",
"Here in the Bay Area: completely and utterly fucked up. Usually just bigger roads get longer times. And it has a fixed pattern that it would rotate against. \n\nComing from Sweden this is extremely agitating as traffic lights back home have sensors under the road to sense traffic and use it to give green to lanes when it's safe and depending on traffic in real time. So no waiting around for 5 minutes when you drive at night and there's nobody there. "
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8k0l0z | how does s thermos/cooler keep things hot/cold and why do the high end ones, like yeti work better? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8k0l0z/eli5_how_does_s_thermoscooler_keep_things_hotcold/ | {
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"Thermos is technically a brand name, but it's been genericized much like \"kleenex\" and \"Dumpster\" have been. That style of container is technically a \"[vacuum bottle](_URL_0_).\"\n\nThey work by having a (usually glass) inner bottle inside a (usually steel) jacket with partial vacuum between them. Vacuum is terrible at transferring heat, so hot stuff stays hot and cold stuff stays cold.\n\nCoolers are slightly different. Similar concept; there's an inner lining, an insulating material, and an outer casing. The insulating material is often some kind of foam insulation, which is also bad at thermal transfer but not as bad as vacuum. \n\nYou can actually make a primitive type of cooler with a terra cotta pot, wet sand, and a smaller terra cotta pot. I haven't tried that yet, but it sounds interesting.\n\nHigh end ones work better because high end everything tends to work better than the bottom-rung gear. Better design and materials, tighter construction tolerances. "
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6kkks2 | how do actors and actresses vomit for movies and television? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6kkks2/eli5_how_do_actors_and_actresses_vomit_for_movies/ | {
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"Cheapest way is to have a mouthful of soup.\n\nFor big volumes of vomit, a hose run up the actor's costume and to the side of the mouth away from the camera is often used.",
"Here's a short video where they have tubes in their sleeves for the large amounts of vomit\n\n_URL_0_\n"
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1u5tom | how can a single wire in coaxial cable carry so much information? hundreds of channels, internet, and voip service in my case. | The single wire hooks into the cable box and it sees like a thousand different channels; it hooks into the modem and handles all the internet traffic from as many devices as I can attach to my network. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1u5tom/eli5how_can_a_single_wire_in_coaxial_cable_carry/ | {
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"Superposition.\n\nBasically, waves at different frequencies don't interfere with each other. You can have one signal at 100khz, another at 110 kHz, on and on down the spectrum until you hit the maximum and minimum frequencies the wire is capable of carrying. \n\n",
"Three levels. \n\nOne is a segmented network, in that the coax in your home is connected to a node that supplies connection to a few hundred homes, or less. Nodes are connected to the headend with fiber optic.\n\nTwo is Superposition, where a number of frequencies can be placed on a wire, and basically not interfere with each other, so they can be independently tuned. They also use QAM-256, which means that at any point in time the carrier wave represents one of 256 values.\n\nThree is packet multiplexing, which that QAM stream is divided into 188 or so byte chunks, and each chunk assigned for a purpose (system, security, channel, IP), and it takes turn placing those packets in the transmission, the more bandwith the more often a packet slot is assigned. ",
"Five year old version: my attempt...\n\nCoaxial cable carries many radio frequency channels at once, with very high quality and consistency. The same thing could be done over-the-air but the quality due to interference and losses would be very low. Also over-the-air has other users and purposes so it must be shared. Coaxial cable signals are completely controlled so it is very stable, and only needs to be shared by customers of the same service.\n Just when you think \" how many users can possibly use the same signals on a coaxial cable?\", another clever design has divided neighbourhoods into smaller areas so that Internet traffic doesn't get overloaded. This makes certain that capacity can always be expanded to meet any needs of the customers. Each neighbourhood gets a similar set of signals, but each are specially designed for each area. \n\n\nThanks to clever international standards, the digital signals carried over coaxial cable have tremendous capacity, and can do many things simultaneously. Some signals are for TV channels, while others are for Internet download and yet others for upload information. The equipment in the home only needs to tune to the correct channels and everything works. ",
"Exactly the same way air is a single medium but can can carry many different sounds and be understood as different sources of information.",
"Frequency division multiplexing. Different channels or purposes (ie. TV vs internet) operate on different frequencies of the same copper wire. _URL_0_",
"Ok, the engineers out there might hate me, but this is an ELI5, so try not to be too analytical.\n\nIt's a bit different for digital and analogue, but digital is a bit easier to explain I suppose.\n\nSo, we know that with a digital signal all of the information is encoded in a series of ones and zeros, or \"on off\". It's like flicking a light switch really quick to send morse code.\n\nSo, let's say that you want to send a message, and each light flick represents one bit of the code. So you start to flick the light on and off once a second. It takes you 1 minute to send your message.\n\nWell, if you want to send a *second* message at the same time, then you can pay attention to the 1 second gap between bit-signals in the first message. What's happening in that gap? Nothing. So let's use it!\n\nSo now we have two signals going. Each one with a 1 second gap between bits of the corresponding signal. Now you can send *two* messages in one minute. But this poses a problem - to someone just looking, it looks like the lights are flickering *twice a second*. The message makes no sense! \n\nWhoever is trying to read the messages needs to know that there are two signals, and that they are alternating. So every other flicker needs to be ignored.\n\nSo, when you want to send more than one signal on the same line, you pick a particular frequency for your message, using the gaps left between other signals. You tell whoever is listening which signals are on which frequency, and ignore the rest. Without knowing which time signature you need to listen for, it just looks like a crazy amount of noise, but if you know what the frequency is, then you can isolate your message. By overlapping the signals this way, you can transmit more than one signal over the same wire at the same time.",
"Can someone use an everyday thing to describe this?\n\nLike cars on a freeway or something?",
"God dammit people. This is \"Explain like I'm five.\" Not \"Explain like I'm a junior technician.\"",
"A little off topic however something even more baffling and impressive is the amount of information fibre optics can carry. I work in main cable hubs, and all the data for a node travels through one tiny piece of glass about as thick as a few strands of hair. A node is about the size of a city block or apartment building, so all the data for hundreds, maybe thousands of people travels through one tiny strand of glass.",
"Think of the cable like a long strip of paper, that constantly feeds from your cable provider to your TV.\n\nYou can write words on this paper in black ink, but you can also write words in red ink, orange ink, blue ink, etc.\n\nIf you wanted, you could write different sentences all on top of one another using different color inks for each, and then pick one sentence to read at the other end by picking out a specific color.\n\nThis is basically what happens with coaxial cable, except there are thousands of different colors in use at the same time, and the TV or modem is very good at zeroing in on exactly the right color that matches the channel you want to watch. \n\nInstead of sentences made up of words, these sentences are made of code that your TV can translate into a picture, or your modem can translate into Internet data.",
"Consider the fact that your old school TV can pick up many channels off the air. Also your radio can pick up many radio stations (also off the air). Now imagine that you had many TV's and radios, all in the same room, all tuned to different channels. One would expect them all to tune in to their channel and receive their desired frequency! This happens as a result of \"tuning\" your receiver to select the channel from every available broadcast in the area. They are all on the air at once - you have to tell the receiver what to listen to.\n\nAll of these broadcasters coordinate their transmissions to keep from interfering. If they don't play nice the system breaks, and then nobody can get their message out. \n\nWhen you plug your cable box into a cable system, you're actually plugging it into whats known as a \"distributed antenna system\" or DAS. For the purposes of this conversation, you can say that the DAS is like a private copy of the over-the-air environment. It is a closed network, so the cable company can develop their own coordination and use it how they like.\n\nModern technologies allow them to use advanced data compression techniques to pack LOADS of data into this broadcasting environment. They are FAR more efficient then their common over-the-air signals (the old channels 5, 7, 13, etc...). \n\nTo answer the internet traffic part, well it turns out that there is a limit. Your entire neighborhood shares that data connection. Fortunately, in a well designed system, the pipe is just so large that each user can get what they want without affecting the others. Because the cable company has total control of their communications environment, they can add capacity with relative ease to respond to complaints. (Though they often don't want to pay for the equipment, and so don't)\n\nTL;DR: The single wire that you see is an antenna that represents a private duplicate of the entire radio spectrum. Cable companies control the spectrum and are able to use heavy compression technologies to get more bang for the buck than over-the-air broadcast. ",
"Cable guy here...\n\nIts this easy. Ok, know how you can tune an FM radio into different stations? Those stations are in the 92-107 MHz range or so, and you tune your radio in to separate stations, and hear the music. Fun.\n\nA coaxial cable does this from 50 to 1000 MHz and your TV, digital TV, digital phone, internet modem, etc, simply tune in the same way to their services.\n\nBecause its so much wider, it supports a lot more bandwidth, and being in a cable and not over the air, there's a lot less noise.\n\nSo regular TV might be 50-400MHz, digital TV from 500-600, internet from 600-800MHz, etc.\n\nEdit: Consider the cable TV coax a magic radio antenna that can only hear your cable company. That's basically how it works. The same way you can fit cell phones, two way radios, GPS and other signals all together over the air, they can cram tons of information inside that one little cable.",
"There are 3 basic ways to send data over the same cable or communication channel/link (which is cable/air).\n\n1. Frequency Divided \n2. Time Divided\n3. Code Divided\n\nMost of these are recognizable from cell phone lingo you've head (TDMA, CDMA), but they apply to most communication links (two things talking to each other).\n\nThe easiest analogy I know of is a cocktail party. Everyone is standing around talking in one room.\n\n1. Frequency Divided\n-Each person talks with a slightly different pitch (some high and some low) and your ear can pick out the difference. It would be easy to pick out James Earl Jones' voice when he is in a room talking with Tiny Tim. The limitation here is how high and low your ear can hear as well as the smallest differences between pitch that you can pick out (all of those things apply to real communication links as well).\n\n2. Time Divided\n-How most conversations work. I talk, then you talk. We don't talk at the same time. This was how many earlier cell systems worked but it became less efficient when so many people started getting them.\n\n3. Code Divided\n-More complicated, but it analogous to people speaking different languages. My ear \"is trained\" to pick out English words. Even if two people are talking at the same volume, at the same time, and with the same pitch, I can easily pick out the English conversation because that's what I know. This analogy is a little loose compared to actual CDMA systems (like most/all new cell phone technologies), but it's close enough. Real CDMA systems use math to make the right signal pop up and the others to look like noise.\n\nThe data on the coax line uses some/all of these ways to communicate (mostly frequency division in most cases).",
"A coax cable is a lot more than a single wire. It is more of a radio frequency waveguide. The radio signals actually propagate through the dielectric(read: plastic insulator) gap between the metal core wire and the metal shield around it.\n\nSo you cannot for example take 14 AWG household wiring and expect to transmit at RF frequencies on it.\n\nNow the second part is about bandwidth. Bandwidth is basically the range of radio frequencies you can transmit through the line. A coax line has a much higher bandwidth than a single wire on your network cable. \n\nThe third part is multiplexing. Due to the way the universe works, you can send multiple radio signals of several different frequencies through the same transmission line and have then all be independently be picked up on the other side.\n\nSo think about a radio. Several different radio stations are all transmitting their signals all at the same time into the air. Yet, we are able to tune a radio to a particular station and receive only what we want. The same applies to cable tv transmissions. All the channels are transmitting - each at a different frequency. Your TV is able to tune in and receive only what you want to watch.\n\nNow if you expand the idea and think about light. Since light and radio are both EM radiation, similar rules must apply, right? Correct. The waveguides for optical transmission are called optical fibers. They too, can carry a tremendous amount of data through them.\n\nTL;DR: A coax cable is not just a single wire. It is a radio frequency wave guide.",
"TIL that even when explained LI5 I don't get this shit.",
"Finally, I can be useful!\n\nI have quickly checked out the first few top comments, and while there's nothing technically wrong, it doesn't ELI5 it well or summarize and bring home how it works in my mind. I have over a decade in cable work, and both classroom and field train new and continuing techs all the time. I will now attempt this ELI5 answer with story time:\n\nThe basic concept in the U.S. is that different frequencies don't interfere with each other, and can be stacked and piped down one tube. Let's start with the old, original analog TV channel:\n\nThere are 3 \"carriers\" to a channel, when looked at on a graph of amplitude (strength) being the y axis, and frequency as the x axis. The first, largest lump is the video carrier, and has the entire picture you see riding on it. The one on the right is slightly shorter, and carries the audio. in between you have a small lump called the \"color burst\", which is simply not present if the channel is broadcasting in black & white. The whole channel is 6 MHz wide, and although the actual frequencies don't line up past channel 12, the same concept was the norm for over-the-air television as cable, until things started going digital. That's up next, but while we're still on analog, it's interesting to know that the frequencies used for cable here are the same bands used for FM radio (analog TV is Frequency Modulation) and broadcast, as well as POTS (Plain Ol' Telephone System). The fact that the paid services are contained in a pipe is what allows for the overlap, and when that separation breaks down, you would get \"ghosting\" (seeing/hearing one channel over another) and some other neat phenomena going on. Let's move on, though, because not much even uses analog anymore, unless you have your TV on channel 3 to watch a cable box's output.\n\nNow, for digital tv. This is where you get more bang for your buck, bandwidth-wise. Cable companies are only allowed certain frequency ranges by the FCC. In 'merica, the norm is 5-1000Mhz, and while 5-42 is reserved for upstream data in most cases, the rest is all downstream and heading out to the customers. IIRC, 55.25 was the original channel 2 video carrier for analog, and many companies that are all-digital still put a blank channel here for reference. Analog channels get encoded digitally, and stuck together into digital carriers, which can be 8-20MHz wide, and can carry as many as 12 channels as of my most recent training (I should brush up, honestly). As this type of data transfer is newer and more sophisticated, it needs a cleaner system to run it, but that means it (at least originally) runs at lower power levels than analog. Old analog was perfectly in-spec at 0 dB/mV with a noise floor around -30 dB/mV. (Making a Carrier to Noise Ratio of 30 great) Digital channels were initially set (in my home system anyway) at 6-10 dB/mV lower than their nearest analog channel, as the two were intermixed at first. Nowadays, with fully-digital service becoming the norm, a perfect-world noise floor is around -50, and the digital signal is still good down to -10 or -12 or so. I may edit this for clarity/completeness later, but for now I'm moving on to internet stuff.\n\nNow for internet and VOIP. First off, although it wasn't the first kind of phone-over-coax, VOIP is literally Voice Over Internet Protocol, and therefore just a service that rides on existing internet service, so as far as delivery, they are the same thing. The specialized modem (called an eMTA) handles the separation and spits out dial tone at/in your house. Anywho, original docsis service was one-way, and used separate, POTS service for the upstream side of things. The downstream is simply another type of digital carrier. Docsis on coax uses a general path called Sonet Ring. Basically, what you have is everybody's downstream data is broadcasted like a digital television channel through the whole \"pipe\" system. The modems themselves each get the downstream data, and only can pick out the part destined for that IP. The modems do not literally pass the data on to the next one, they all receive it, technically speaking. This led to common misconceptions about cable internet in the earlier days, such as \"everybody shares the same bandwidth.\" While this is technically true, the system was always over-built by a factor of 2 or so vs. projected penetration/usage. Yes, everyone had the same down and up pipes, but there was plenty of flow to go around, and the causes for one customer borking up the rest's service have mostly always been noise insertion. This is still the foremost problem today where one subscriber can fuck up a block or apartment building's worth of service. Moving on in the timeline of advancing services, Docsis 2 simply made it standard for there to be a digital upstream path in the coax (between 5 and 42 MHz), and multiple downstreams, which created more bandwidth within a node. What you get, instead of one big, increasingly overburdened downstream path for a node (about the size of one average neighborhood or 5 3-floor apartment buildings, give or take), you have 3 or 4 downstream paths, and the one your IP address on is the one that gets sent the relative data for that IP. It is now relative to point out that there only being one upstream and several downstreams in any given leg of coax is by design, and because people generally download more than they upload in residential service, and why the packages align to this (12Mbps down, 3 up etc.). Docsis 3, the new fancypants shit, requires an even cleaner network with more emphasis on balancing power levels, but achieves faster throughput by bonding downstream channels together. So if you have 5 downstream carriers, the modem can use 2 or 3 of them simultaneously, and while they usually aren't right next to each other, this works fairly similarly to N wireless, and is the same way in which N gives you faster speeds - it's called \"channel bonding.\" \n\nSo now, I'll give some homework if you're interested. If you're on a cable modem, open a browser and surf to 192.168.100.1 and go exploring. You may have to google the default login for your modem brand/model to get past the splash page, but this is the number one thing I have people tell me over the phone when I get a call from a friend along the lines of \"Hey, you're a cableman and my internet sucks.\" \n\nSome neat side notes:\nThe signal doesn't even ride down the whole copper center conductor. It actually sits in a ring, closest to the outside, with 5MHz closer to the center, and 1000MHz near the outermost region. For reasons involving these physics and the relatively small bandwidth window (as compared to satellite), many cable companies actually use copper-coated aluminum wire in your house. If you cut a piece of scrap coax that a cableman gave you, you should see the inside is silvery in color, and not copper. It's cheaper when each truck can spool off 1000 or more feet per day into various houses. Satellite services use (inside the coax) up to 3GHz frequencies, and therefore need better conduction, and use solid copper center conductors. \n\nThe bit about interference early on called \"ghosting\" has a term - it's called ingress. That means something \"leaking\" into the cable. (Conversely, when you have leakage, it goes both ways, and there is also egress occurring. Since the FCC mandates that cable networks stay contained, they literally fly planes around periodically and \"listen\" for cable-only stuff being transmitted into the air, and if a threshold is reached, they fine the shit out of a cable company.) Channels 3-12 line up exactly with OTA when we're talking analog frequencies, and that is why often the cable company would move the locals around on you. Broadcast 12 would be moved to Cable 11, etc, and if you had an ingress problem, you would see 11's picture \"bleeding\" into 12. For a long time, cheaper/malfuntioning TV's and VCR's would be the primary cause for this, and was always a mofo to have to tell a customer \"your shit is broke, not ours, and there will be charge on your next bill for making us come out to tell you that.\" \n\nGot questions? I can talk about this shit all fucking day long, so long as you don't mind cuss words peppered in. AMA here, because I did an actual AMA some time ago by request, and it kind of fell flat. I don't think I'm going to bother this go-round, even if requested. I have also spent much of my work hours with a fake-ish persona on to make all the related companies look good, so can't stand to pull that shit off-the-clock. Straight talk with some silly-talk is what reddit will get from me, not any of that sugar-coating nonsense the guy in your house (sometimes me) may put on it.\n\nTL;DR: Hat-tips and referrals to the following commenters that explain different of what I did, albeit less all-encompassing, in a much shorter manner (some give more detail in the specifics of data streams themselves):\n_URL_0_\n\n_URL_3_\n\n_URL_1_\n\nSpecific to how so many different types of separate signals look like riding down one path, check out this super-sexy .gif: _URL_2_\n\n\n",
"Cable tech here. Cable works on frequencies, these frequencies go up to about 1250mhz. In my companies case the usable Frequencies stop at about 850 but there are certain things that really high frequencies are good for such as home network communication. Each frequency carries data, wether it be internet, a tv station, or phone. Since different frequencies can work together without interfering each other they can all go on one piece of cable. Your set top box, modem, and phone modem interpretation these frequencies and transmit data accordingly. Recently digital cable is taking ove analog because analog channels take up a lot of frequency. And analog channel uses about 6mhz, with digital you can fit something like 6 stations (don't quote me I'm on the toilet right now) into the same space.\n",
"ELI5 answer hopefully. \n\nMikeavelli gave the correct answer but I am going to assume you don't know what kHz and frequency are.\n\nWhat do you suppose frequency means? Frequency is how often something occurs in a certain amount of time? Right? \n\nEM (electromagnetic) waves can also have such a quantity of frequency. It basically tells you how \"squished\" the wave is, horizontally speaking (vertical squishing changes the amplitude, which you can ignore this). The measurement of this frequency or how \"squished\" the wave is is Hertz or Hz. When we say kHz, we mean kilohertz or 1000 Hertz. Hertz is a unit of measurement like inches or gallons or degrees Celsius. A crazy thing to understand is that if I had a set of waves at different frequencies (or \"squishedness\") all hitting me in the face at once, I can separate them. \n\nHow do I separate them? Just like a water filter filters smaller particles from larger ones, we can filter these EM waves and separate different frequencies. Our eyes do this naturally for the frequency range of what we consider the visible spectrum. We see different colors because of this. Different frequencies = different colors. Now instead of your eye, you can design your own filter to separate frequencies. But why do we want to separate them?\n\nThe next time you look at your radio in your car, for example, you see the numbers maybe 101.5 or 98.1 on FM. These numbers are MHz or Megahertz (Million Hertz). You can tune your radio from, say, 87.7MHz to 107.9 MHz. This \"tuning\" is basically establishing what frequency waves you want to filter. \n\nNow, in the coaxial cable, your cable company already knows this range for tv broadcast (designated by the FCC) and the cable box can filter this range which makes different tv channels. So, you can say something like 4MHz is channel 2 and 4.2MHz is channel 3.\n\nYea, but even with the ability to separate all these channels how can I be streaming a 1080p movie on any particular channel with just this one copper wire? This is where it gets a bit too complicated for ELI5. \n\nThere is something called Quadrature Amplitude Modulation (QAM) that allows for a dense amount of information to be transmitted over a clean (non-noisy) channel. Most cable companies use this because there is not a lot of \"noise\" in the wire as opposed to in the air. If QAM performed well in noisy conditions, then you probably wouldn't have an FM receiver. You would have a QAM receiver. If this doesn't make sense, don't bother about this part. Most graduate students taking a grad level communications course wouldn't know about this either. I won't explain QAM, but just know that it is a method of communications which works really well in a non-noisy medium. By \"works really well\" I mean it allows for a higher density of information to be transmitted. I get that air has a lot of white noise, but what makes coaxial clean? If you were to take a really sharp knife and cut a coaxial cable, you will see multiple layers. One layer is a copper shield layer. This shield basically absorbs all the noise or unwanted signals in the air. There is an insulator between this shield and the actual communication wire which is the center copper wire. So, this means the communications wire at the center never has to worry about a stray signal getting into its stream. Thus, we can call it clean. \n\nThere is also something called data compression that allows me to take my data and turn it into less data with the same amount information conveyed. So lets say I have a message that I want to send to you. Lets say I know a method that can cut this particular message in half and it still retains the exact meaning. Now I only have to send 1/2 the original intended data and you will still be able to read my message. This, too, is an oversimplification. Data Compression is an entire field on its own. \n\nTLDR; There are ways to increase the amount of data transmitted dramatically by:\n1) Separating data streams into varied frequency ranges\n2) Use a method of data transfer that works really well under clean (non-white-noise or non-stray-signal) conditions.\n3) Compress the shit out of the data.\n\nedit: Electrical Engineer",
"I worked for a large cable company. Here's how one of the headend techs explained it to me. \n\nThey were running an 850 plant. Meaning they ran 850 kHz across their coax plant. Each frequency carried something different.\n\nCould have been unicast Video on Demand, Multicast TV channels, Cable internet upstream or downstream. \n\nThere were devices that put signal onto the coax, and other devices that read that signal on the configured frequencies. They bunched them all together. \n\nSo next time when you change your channel, all your set top box is doing is tuning to a different frequency that it's been programmed for the corresponding channel or service. Your DOCSIS modems utilize multiple frequencies for upstream and downstream based on your service level. VOIP is just another service on another frequency.\n\nThe technology they were starting to implement before I left was called Switched Digital Video. Instead of using the coax for EVERYTHING, when you tuned to a channel, your set top box would reach out to a device at your local hub and request just that stream. It would then be subscribed to a multicast of that stream. Now your cable line back to your device is just handling one stream. This means the stream could be fully uncompressed HD, and you would have the bandwidth to pull it off.\n\nIt's pretty cool stuff.",
"Not seeing a real ELI5 answer so here is my attempt...\n\nThe amount of information a system can effectively carry is controlled by how fast the system can \"talk\". When we speak, we take a sentence in our head and break it up into audible syllables that we have to physically form with our mouths. Speaking faster and faster, we will all reach a point where our mouths cannot move fast enough to pronounce each syllable clearly and the overall message will be garbled.\n\nAlthough it seems instantaneous in human time frames, copper wire can only be turned on and off so fast. To talk with a series of on/off pulses past the physical limits of one wire, it is common to add more wires in parallel; think of ethernet, VGA, DVI, or HDMI cables. A coaxial cable isn't a simple copper wire, but basically a tube that a radio wave can travel through. This is a very different medium where we can measurably change radio waves **much much** faster than we can electrical signals in wire. So radio waves fundamentally talk faster than copper wires.\n\nThink of radio waves (Mr. Coax) as someone who talks so fast they can pass on 5 conversations at the same time. Each time 5 people say a word, Coax says the 5 words in order really fast. When Coax does this, people on the receiving end get way more information than they need, so they only listen to the part of Coax they care about. \n\n > I---We-You--Cake-Time\n\n > am-are-arent-is----to\n\n > fat-bad-good-good-go\n\nReceiver 1 only listens to the first word of the five, receiver 2 only listens to the second, and so on. This is similar to what radio tuners, modems and cable boxes do, but it is of course much more complicated. The first word represents a TV channel, second word represents VOIP, third represents internet. The important thing is that Coax talks so much faster than these data streams that it can effectively carry on all these conversations at once.\n\nModems, cable boxes, and a bunch of other machines behind the scenes coordinate how Coax organizes these conversations to ensure his words can be understood."
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"http://www.reddit.com/r/explainlikeimfive/comments/1u5tom/eli5how_can_a_single_wire_in_coaxial_cable_carry/ceexm6u",
"http://www.reddit.com/r/explainlikeimfive/comments/1u5tom/eli5how_can_a_single_wire_in_coaxial_cable_carry/cef6cac",
"http://www.reddit.com/r/explainlikeimfive/comments/1u5tom/eli5how_can_a_single_wire_in_coaxial_cable_carry/ceeuomy"
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f0iffr | why can't you donate blood in the first 6 months of getting a tattoo? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/f0iffr/eli5_why_cant_you_donate_blood_in_the_first_6/ | {
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"Because getting a tattoo breaks the skin and if a dirty needle is used and you get hiv, it takes a few months for hiv antibodies to show up in your blood stream. \n\nDetecting for hiv antibodies is how we detect hiv. We can't directly test for the presence of the hiv virus. So if you got hiv and gave blood before antibodies show up (ie within 6 months), when they test your blood at the time of donation and dont detect hiv antibodies (because its less than 6 months) then they assume the blood is uninfected and if they use it, someone now got hiv.",
"You can potentially get diseases from tattoo needles.\n\nThey screen the blood you donate for diseases. But sometimes it takes a few months for diseases to be able to be easily detected. I've heard it can take HIV like 3-6 months to show up.",
"the exact rules depend on location, but according to their website says in some places if the tattoo parlor is government regulated and the needles were sterile, there's no wait at all. \n\nthe wait is a precaution in case something was transferred to you via a non-sterile needle or incorrect sterilization methods.",
"Because tattoos break the skin with needles, and used needles can potentially transmit diseases like HIV or Hepatitis C. Blood is screened for diseases, but it can take before a test can show up positive. Having a waiting period makes it possible to screen donated blood and be confident that the tests are correct.",
"Historically, some tattoos parlors haven't always been careful with their needles and were a vector for bloodborne pathogens.\n\nWhen it comes to the blood supply, safety trumps \"fairness\", I wasn't able to give blood for a few years because I visited Africa."
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2nlzx9 | how is it possible for the kinder morgan pipeline in bc to still an issue after various local communities have rejected the proposal ? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2nlzx9/eli5_how_is_it_possible_for_the_kinder_morgan/ | {
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"Because power corrupts. Most politicians don't care what their constituents think until it's around election time. Maybe those representatives know they are on their way out anyway so they try to secure that cushy consulting/lobby job for the major defense and oil corporations."
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e0el6y | when some 'runs across america' or does some stunt for charity. how's does it actually benefit any charity? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/e0el6y/eli5_when_some_runs_across_america_or_does_some/ | {
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"It does in 2 ways. First it raises awareness of the charity and whatever it is they stand for. Spreading knowledge and building credit for that organization.\nAnd then financially through donations or pledges. Some people run just for the awareness, but most people donate and have other people donate. Some get pledges that if that person completes the event, they will donate so much towards the charity. And then some events require minimum donations just to participate. My office participates in a volleyball fundraiser every year. Each team pays a certain amount to enter and then everything else is complimentary. So say the cost per player is $50, the min donation for a team of 10 is $5,000. So the charity keeps $4500 of the $5000 after expenses for the event. Also because it's a charity, they can often keep costs lower by having some parts of the events sponsored, like meals, drinks and snacks sponsored by a charitable donation from a large company who both donates but also uses it as a marketing opportunity. So at a race where you see water bottles being handed out with a mobile phone company logo on it, it was their donation to the event to sponsor the water, and they threw the marketing in for good measure, all at no cost to the charity.",
"In multiple ways, \n\n1) they raise money through sponsorship which goes to the charity to fund work etc.\n\n2) outrageous tasks like running a continent, swimming an ocean etc draw media attention, clicks, and sponsorship from people that would have otherwise not known about the even or the cause:\n\n3) even if people don’t donate straight away, or at all, it can raise awareness that the charity exists in the first place. This can result in future donations to charity inc leaving gifts in wills.\n\n4) if people are doing long distance events and need rest breaks, putting up for the night etc, business will often comp the person doing the event for brownie points. This helps raise awareness again, and means more money can be diverted to charity."
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1y1aq8 | why do people like warren buffet continue to try and make as much money as possible, when they have so much that they could never spend it all? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1y1aq8/eli5_why_do_people_like_warren_buffet_continue_to/ | {
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"Well, in Warren Buffet's case, when he makes money, he's really raising money for charity because he's been very clear about wanting to spread his wealth and share it with good causes. Other people may feel the same, such as Bill Gates.",
"It's a hobby.",
"I can think of a few possible reasons, but I can't really answer for Buffet because unfortunately I'm not him:\n\n1. For charity (probably true for Buffet, a huge philanthropist)\n\n2. For future generations. Why secure your kids' futures and quit, when you can secure your great-great-grandkids' futures\n\n3. Boredom. What else are you going to do all day if not work? I'm sure even luxury yachts and supermodels can get boring after a while\n\n4. To be the best. People are competitive, and wealth is the easiest way to measure success ",
"Its mostly because they enjoy making money. It isn't about the money itself, its more like a giant game and they want to get better at it.",
"When you control massive wealth you can do things nobody else can do. You get called by Presidents and Potentates when they need help or want your opinion. You get invited to the most interesting secret meetings where the strings that move the world are pulled. You get a seat behind the curtain.\n\nBeing an active investor is what keeps you in that seat. If you put your money into a passive investment vehicle and ignored it, people would ignore **you**. Only if you're seen to be willing and able to move the kind of capital that changes markets do you get to be a real \"insider\".\n\nBuffet loves being an insider (who wouldn't?)\n\nHe's also been doing it his entire life. Clearly he loves it on some fundamental level. He is probably really intrigued by what he sees happening over the very long term and wants to remain in a decision-making role as he watches to see if his theories about how the world works are validated or not.",
"Well, in the case of Warren Buffett, what I'm recalling now is an explanation he gave sometime (in the 1990s?) when somebody asked him why he donated so little to charity. (I can't recall where I read this; it was either in an article or a third-party biography, so don't quote me on this!) His response was something along these lines: running a business that makes a ton of money by honest means is a contribution to society—it creates jobs, and provides people with goods and services that they want, etc. So he believes that while he's still got the talent to multiply his business, that's the best thing he can do with his money. He'd rather make a lot of money now and donate it when he dies than donate it now, because he believes that way he can give more.\n\nMind you, Buffett's not your regular billionaire. Most of them are, to be blunt, just greedy.",
"If you've had sex and made a baby why bother to have sex ever again? Aren't you done at that point?",
"Warren Buffet in particular has said in interviews before that he enjoys his job because he is good at it. \n\nIt's basically the same as if someone was good at basketball or some other sport, they would enjoy doing that a lot as well. It's just the thing Buffet is good at is making billions of dollars.",
"Professional Billionaire Here! ***cough*** \nOnce you've made a good chunk of change you can get addicted to money, not physically, but mentally. It's not even the money you get attached to it's the power that comes with it. It's like a power disease that leads wealthy people to hoarding, which the top 2% wealthiest people like to do very well. Some people stock up on food and bullets, others stock up on investments and money. They could be filling a void, or just plain power hungry. Either way their addiction is effecting earth's population more then they realize. Unless they're also addicted to helping, which isn't usually the case unfortunately. ",
"It's a game to them. It's a high just like gambling. "
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16s1lt | why is being "cisgender" bad? | An internet term that has been around for a while suggests that being cisgender (identifying yourself as the same gender as you biologically are) bad from the perspective of a trans-person. Why? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/16s1lt/eli5_why_is_being_cisgender_bad/ | {
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"It's not bad. It's just *different* from the perspective of a trans person, in the same way that being transgender is different from the perspective of a cis person.",
"Can you give a source of this actually happening? I know the feminist community can be ridiculous sometimes, but I've never seen them say that being cis is actually *bad*. You may be taking things out of context.\n\nThey like to talk about cis-privilege. ",
"Cisgendered is commonly used in a couple of ways:\n\n1) It's a way for people to identify a group commonly called normal in a way that doesn't imply anyone else is abnormal.\n\n2) It's used to otherize people who are not accustomed to being otherised to encourage empathy toward people who are commonly otherized.\n\nIt's not usually used pejoratively, but how it could be considered bad is in the context of political correctness. Political correctness is an attempt to codify sensitivity. It's most strictly adhered to by people who feel other people are not sensitive enough and therefore need a flow chart or map to be empathetic and sensitive. For some political correct proponents anyone who is not marginalized would be viewed with a fair amount of cynicism and possibly anger. To them being cisgender would be bad because a cisgender person is part of a group that by the nature of it's existence marginalizes anyone who isn't part of the perceived majority.\n\nMy own feelings on it are that these margins are illusionary created by a counterfeit normalcy and otherising people is always wrong, be they cis, trans or anything else. Fair warning, this view is considered bigoted by people who view inclusion as a dismissal of people who are different. ",
"I've never met a trans* person who thought the term cis* was bad. Cis- is the literal antonym of trans-, after all.\n\nIn fact, most of the complaining I've heard was actually from cisgendered people, because of the 'othering' effect. Cis- categorizes and boxes in a lot of people that aren't used to beng boxed in and categorized.",
"It's not bad at all. Cis is to trans what straight is to gay, and that's really all there is too it. ",
"It's not. *Assuming everyone else is, or treating people like freaks if they aren't,* is bad for the same reason that it's bad to assume everyone in your audience is straight, white, or male.",
"Trans person here! Being cis isn't bad. Just realise and acknowledge the privileges you have, is all. Also, being white isn't bad, being male isn't bad, and being straight isn't bad, but again, these will all give you priveleges that you should acknowledge."
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1fwc2u | why don't military aircraft use "sky" camouflage? | I don't understand why ground soldiers wear the green and brown camo to blend in with trees and bushes, and those in the desert use desert camo (even the vehicles) but aircraft and watercraft don't use camo that more suits their surroundings? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1fwc2u/eli5_why_dont_military_aircraft_use_sky_camouflage/ | {
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"Basically because nobody shoots at them visually any more. They are much more concerned with making themselves invisible to lasers, radar, and heat-seeking missiles.",
"Most of them do just not in the way that you think.\n\nUS Navy ships are painted a color called 'Haze Grey'. On the ocean, from a distance (think on or near the horizon) this color can cause a ship to nearly disappear or be much harder to spot.\n\nMilitary aircraft are painted the same and/or similar colors for the same reason.\n\nI assume you're really asking 'Why aren't planes blue?'. The answer to that is due to cloud cover, different times of day, different areas of the world, the sky is very rarely truly blue. Most of the times it's varying shades of blue and grey. \n\nThere was a time when we used to, and TTBOMK some countries still do, paint the top portion of the aircraft in a camouflage scheme and the underside blue so that when viewed from above the plane will blend in with the ground and from below will blend in to the sky.\n\nI believe this practice has stopped for the most part because as Radar has improved, the ability to hide an aircraft has become smaller and smaller. Why spend the time, money, and manpower to paint a camouflage paint scheme on an aircraft when a Radar can pinpoint it's location with absolute accuracy? \n\nOther planes whose mission does not include flying at altitudes low enough to be spotted by the enemy are painted different colors usually shades of off-white most probably because it's a cheap color.\n\nSome planes are painted black because their missions are either flown at night and/or the paint itself has properties that block, refract, or absorb radar waves.",
"Actually they still do.\n\nPlanes are still camoed, Look at Israel f-16s and compare them to european f-16s, they have different color scheme. Some of them have false canopy on the underside.\n\nFighters still need camo in close combat, since in the high speed movement you have to acquire targets in sub-second with your eyeball mk1 and camo is a significant counter-measure. The underside is often painted light color to blend with the sky and the top is painted whatever the ground would look like.\n\nB2s are painted black, as they are expected to operate in the dark."
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c0meio | why is depth perception messed up in low light? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c0meio/eli5_why_is_depth_perception_messed_up_in_low/ | {
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"The sensors in the eye are not spread out uniformly, the eye is not a camera. The ones that feed into depth perception best, the cones, are denser in the center of the field of view. The ones that see in low light best, the rods, are denser around the edge."
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2gtw4e | when the milky way and andromeda collide, what will happen to their supermassive black holes at their centers? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2gtw4e/eli5_when_the_milky_way_and_andromeda_collide/ | {
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"They would combine into one even bigger black hole",
"They will orbit each other and eventually merge, probably.\n\nOr one/both will get thrown out/they will just pass by each other.",
"Space is extremely empty! Two galaxies can \"collide\" without much of any physical matter ever interacting. The gravity that the mass of both galaxies has will do the vast majority of the interaction. This is how our galaxy has the large and small Magellanic clouds. Both of which are visible from the southern hemisphere. \n\nEDIT: The SMBH at the centers of these two galaxies will have to be within close enough proximity for anything to happen. Chances of this happening is probably highly unlikely.",
"The chances of them colliding with each other during the initial collision is extremely remote.\n\nIt's moderately likely that they will absorb one or more stars during the collision before they, like 99.99% of the other stars in each galaxy, pass out the other side unscathed.\n\nThe courses of all the stars and massive objects in the Milky Way and Andromeda galaxies will certainly be distorted heavily and the shape of each galaxy disrupted as they slowly ocillate between 2 distinct galaxies and a single amorphous galaxy. Over many millions of years the 2 galaxies will eventually completely merge and it's likely the 2 black holes will one day merge after they eventually come within an very small distance (~1 light year which is tiny on a galactic scale) but there is no certainty that the 2 will end up in the exact same region until many millions, even hundreds of millions of years have passed.",
"Things inside each galaxy are so far apart, there is enough space that most of the galaxies will simply just pass each other by; this includes the black holes at the centers.",
"Actually most this thread is wrong. \n\nSpinning black holes rarely merge. Its more likely they'll end up in orbit of each other, and slowly move together. But when they go to merge their angular momentum will cause one to shoot off into interstellar space.\n\nIt'll convert most of its spinning momentum into a direct velocity and fly off out of galaxy (where it'll likely never be heard from or seen again). "
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9catw0 | why does parallel parking only work when reversing at the start? | edit: Thank you all for your explanations. I believe I now have a firm grasp of why reversing is easier to complete a parallel parking maneuver. Thanks everyone again :) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9catw0/eli5_why_does_parallel_parking_only_work_when/ | {
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"Because your turning wheels are only at the front of your car. As your back wheels get where they need to be while reversing you can turn your front end in. Otherwise you would need to drive onto the curb or much farther ahead to drag your back wheels into the parking space. It’s not that you can’t do it forwards you just need less space while reversing. ",
"This reminds me of my job. Same reasoning when I see the forklifts. They are made so back wheels turn instead of the front the wheels which allows the forklift to turn at much sharper angles far more easily. When you put your car in reverse its essentially the same concept. Your front wheels (which are the wheels that can turn) become the back wheels in regard to the direction the car is going. So I suppose when you back into a parallel spot it makes it easier for the car to turn sharp enough to get in there. ",
"The best way to explain this to someone is with a shopping cart. You can't quite push into a \"space\", but if you push the cart from the other side it's easy.\n\nBy the way, this is why stand up forklifts have rear steering wheels. "
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b3g9tz | how do stealth fighters like the f-22 or f-35 work? | How does the stealth technology in these aircraft work? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/b3g9tz/eli5_how_do_stealth_fighters_like_the_f22_or_f35/ | {
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"Radar works by sending a radio wave out. The radio wave hits the surface of an object and is reflected back at the radar station. It measures the time it takes for the radio wave it sent to get back and that tell you how far away and in what direction an object is.\n\n & #x200B;\n\nMost airplanes are made of rounded shapes. So not matter what direction the airplane is facing there is always a part of the plane that can reflect the radar signal back towards the radar station. The stealth airplanes are made up of flat surfaces. When radar hits the flat surfaces the radio waves are not reflected back to the radar station but they are reflected away instead. They also use materials on the surfaces that help absorb the radio waves instead of reflecting them. Stealth airplanes are not 100% invisible there are certain angles that the radar can hit the aircraft and reflect straight back to the radar station so that it can detect it.\n\n & #x200B;\n\nIf you have a reflective ball like a Christmas ornament you can see the process illustrated with light waves instead of radio waves. Because the Christmas ornament is rounded you can see your reflection in the ball no matter what angle the ball is from you. But if you take a flat mirror you can only see your reflection if you are facing the mirror at a very narrow angle.",
"To add, some radar is capable of penetrating the skin of an aircraft and reflect off internal structures. Stealth technologies can use geometries inside it's skin to act as traps, where radar waves bounce around inside and never escape back out toward the receiver. Another method is to use paint with iron in it to absorb still more or other frequencies.\n\nOther things to do is to produce as little electrical noise as possible - any conductor carrying a current is an antenna transmitting electromagnetic radiation. This can make you a beacon. That also means no radio. Another means is to scatter your engine exhaust to have a low thermal signature, so you don't look like a hot streak - I think this comes up more with heat seeking missiles, if those are even still used.\n\nYou can also employ countermeasures. Chaff is basically strips of aluminum foil that reflect radar waves and confuse enemy radar. Or you can use a jammer that fills their receivers with EM noise, provided they don't track your jammer itself through counter-counter measures, as I alluded in the paragraph above about being an EM beacon.",
"Here's a [search](_URL_0_)."
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3z8tt4 | how do "entrepreneurs" develop their potentially lucrative ideas without having them stolen by others at any point in the process? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3z8tt4/eli5how_do_entrepreneurs_develop_their/ | {
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"In secrecy. There's usually a secrecy contract on work places.\n\nAlso when it's a proven concept to some level, people get patents on them.",
"Most often, the idea an entrepreneur implements isn't really *that* unique -- several people have similar ideas. Consider Uber and Lyft, or Coke and Pepsi, or your favorite 5 burger-and-fries restaurants, or your closest 5 dry-cleaning shops. The uniqueness of the idea is one of the smaller contributors, or even zero contribution, to many businesses' success.",
"Because an idea takes a lot of time and dedication to implement. If someone's stealing it, they're already late to the game and without the initial motivation (and probably understanding) that started the original idea. \n\nAlso, it's very common for successful ideas to be laughed at in the beginning, instead of stolen, because we're terrible at predicting what's going to go big. A website to allow strangers to sleep at your place for a few bucks? Right, like that's ever going to work. "
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8zh1a8 | why do eyes have that awesome pattern around the pupil and what is the purpose of the coloring? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8zh1a8/eli5_why_do_eyes_have_that_awesome_pattern_around/ | {
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"The colored part is called an iris and is a muscle used to control the size of our pupil, the black part of our eye that allows light to enter. \n\nThe color is caused by a mutation that reduces the amount of melanin contained in the iris, this lack of melanin allows light to be reflected out of the iris in hues of blue or green and different shades of brown.",
"My girlfriends eyes are like that, I know what you’re talking about. Her eyes are blue but have a orangish, yellowish halo surrounding the pupil. I have no idea what it’s called or why it happens but if you remind me I’ll update this with a pic tomorrow "
]
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||
2ylgzh | why do nfl players trade or let their players leave so frequently and so easily? | The Saints Traded Jimmy Graham. He's awesome. Top 2 TE. Eagles let Maclin sign with another team. Do you think the original team knows they aren't worth the money?
The movement -cuts, free agents, trades seem so much more blockbuster in the NFL than other pro sports. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ylgzh/eli5_why_do_nfl_players_trade_or_let_their/ | {
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"I think it's about building the best team you can for the money. Sometimes you have a great player that's worth the money of 2 pretty good players. It's all about the salary cap in the NFL. ",
"O_O Way to find out that one of my favorite players has left the team I love. I may go cry now... \n\nThe reason though is the NFL has very strict salary caps in order to maintain fairness and parity in the league. The Saints were WAY over cap so many high dollar players would have to be cut in order to sign new talent. "
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2ltgbw | why do some people get bit by mosquitos much more often than others? | I went on a hike with about 10 friends. I was the only one to be bitten. By the end of a 2 mile hike I had 5-10 huge welts on my arms and neck. No one else had a single bite. So what gives? Is it body temperature? Is it my blood type. Is it my scent? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2ltgbw/eli5_why_do_some_people_get_bit_by_mosquitos_much/ | {
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"It's basically because of the amout of Carbon Dioxide you exhale. People that exhale more Carbon Dioxide than others have a higher chance of getting bit. Also, scent (sweat) makes a difference. ",
"I'd like to add a question to this question.\n\nI'm Caucasian and when ever I'm around Asian people they get bitten and I'm left unscathed. What is going on here?",
"You may get bites but not know it. People react differently to bites. I have been in flea infested hotels with my gf and she gets bit and so do I. She gets bumps from bites that itch - but the bites don't effect me. ",
"Type O blood has been shown to be more attractive to mosquitoes. Also CO2 as someone else in this thread mentioned. Sweaty people are more attractive to them too, and men more so than women.",
"A friend's cat got fleas once, the cat was in my lap for a good 2 hours before I looked down and saw a little black dot jump off her back towards the floor. I was the first to spot the fleas. I was sure I'd be infested by the time I left.\n\nTurns out my friend and his Dad were the only ones to get bit (viciously, I might add), myself (female) and his mom were flea-free.\n\nThey ended up getting the house fumed. But I always found it wierd that only the women exposed were left untouched. They didn't even travel home in my clothes or backpack. I was always flea-free. :D\n\nMy buddy was itchy though. He said it sucked. XD\n\nEdit: forgot to mention I almost never get bitten by mosquitos, and when I do they never swell or itch.",
"From a 5 minute google scholar search:\n\nMosquitoes respond to:\n\n* Heat\n* Moisture\n* Oils/odors\n* CO2 levels\n* Body position/motion\n\nDifferent mosquito species respond differently to each of these factors. You may also be more responsive to bites depending on your immune system and body tissue composition.\n\n_URL_0_",
"You may want to hit up /r/askscience instead. I can already see how this thread is going.",
"Mosquitoes are attracted to estrogen. This is why most women get bit more than most men. In an ad, they show mosquitoes not biting skin, what they don't tell you is that the skin is on a man. Source: my FIL is an entomologist at a large university who works with a company producing different bug repellents. I get this lecture once a summer.",
"Mosquitos are attracted primarily to CO2 and heat, but other factors such as your sex, whether you have been drinking alcohol or exercising, and even what you have eaten can subtly change how attractive you are (being female, recently imbibing alcohol, and recently exercising all make you more attractive to mosquitoes)",
"All this armchair physiology, I don't know who to reply to. \n\nBreathing more heavily does not make you produce more co2 (well slightly due to increased metabolism). The amount of co2 produced is directly proportional to the metabolic rate. Increased ventilation is a consequence of increased co2 production, not the other way around. \n\nIf you breathe heavily intentionally without the increased metabolism, you will blow of your co2 and the partial pressure in both your blood and end tidal will decrease.\n\nThe level of co2 in a conscious persons blood is regulated very tightly.\n\nAs for the temperature thing. You will feel hot to touch when you're losing heat to the environment, again your core temperature is very tightly regulated",
"An old wives tale mentioned increase the amount if vitamin B in your diet to decrease bites. My wife and son get eaten alive, but after increasing vit B through eating vegemite on toast and drinking berocca my son hardly gets bitten at all now. \n\nVegemite/ marmite and berocca are well known to Brit's, kiwis and Australian's.",
"Simple. Some people eat more garlic than others. Not only does it keep vampires at bay, but mosquitos tend to avoid it. I believe garlic works on most of the blood-sucking species.",
"In ELI5 form, I will say yes, it is because of the CO2 that we exhale that causes the initial attraction. But as you and so many of us have observed, some people tend to get bit more than others. \n \nThere are a few theories about why, but studies have recently shown that the composition of bacteria living on our skin can affect the attraction of mosquitoes. Different bacteria release different waste products and some of those are odorous. These odors can either act as attractants or repellents to the mosquitoes. Not everyone has the same amount and same type of bacteria living on their skin, so different people will have different odors around their body. \n \nInstead of posting a bunch of links to different studies, [Here is the google scholar search](_URL_0_)",
"from my hiking experience, and the experience my 50+ years hiker godfather shared with me (and we are the only ones that don't get bitten (too much) in 50 ppl groups) : when you start to scratch the first mosquito bite spot, you opened the pandora's box, because first, you start waving your hands in order to do it, which increases your body sweating, and attract them with your motion, and secondly, you let the scent of their enzime from the bite mark (the one that makes you scratch) go around and it attracts other mosquitoes ... mental stability is the best way not to get bitten, don't let them annoy you, you are stronger than they are, really! "
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5o8idn | can you really not catch a cold from being cold? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5o8idn/eli5_can_you_really_not_catch_a_cold_from_being/ | {
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"You catch a cold by getting a virus. Cold can suppress your immune system and make you more susceptible to getting sick, but cold by itself cannot directly make you sick. You have to be exposed to the cold virus to get a cold. ",
"The cold is a virus. If you are not exposed to the virus you can not catch it. In some studies, cold weather have shown a slight decrease in immune systems while being cold. However, in cold weather, more people spend time indoors in close quarters increasing close contact with those that may be sick. "
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