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6s3glr | if some humans have neanderthal dna while others don't, does that mean some humans are at least somewhat of a different species than others. | This has been really bothering me lately and due to my OCD has been constantly on my mind has been causing me a lot of distress. I recently learned that some humans have Neanderthal dna due to interbreeding while others don't. Given that Neanderthals are a different species (I understand the definition of species is somewhat loose), am I not fully human and instead a human-neanderthal crossbreed, whereas some of my friends who likely would not have Neanderthal dna be fully human and therefore a different species? Or would we both be considered equally human beings? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/6s3glr/eli5_if_some_humans_have_neanderthal_dna_while/ | {
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"No. The definition of a species is whether or not members can interbreed. All humans can interbreed as a species. We're all one breed much less not the same species. ",
"Homo sapiens neandethalensis (neandertals) is a sub-species of homo sapien sapien (modern human). Both are homo sapien (human) because they are very close cousins, close enough that they could breed and make successful offspring together. The definition of a separate species is that it must be another group of organisms that cannot mate with the main group to produce viable(fertile) offspring. So by definition neandetals were not a different species. ",
"The definition of species is indeed somewhat loose but most agree on the basic that successfully interbreeding and having fertile offspring means that you are part of the the same species.\n\nThis is why many people now think that Neanderthals should be considered a different subspecies of humans not a different species altogether.\n\nIt is similar to wolves and dogs which can interbreed and are the same species but still obviously different enough to tell them apart.\n"
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157tf9 | on gawker websites i need to spam the back button to actually go back, why? | It's almost like I'm being redirected, then I go back to the redirect page but it pushes me forward.. so spamming it lets me go back faster than the redirect page works... It's like this for me on every gawker website (kotaku, gizmodo, lifehacker)
Chrome Version 23.0.1271.97 m
windows 8 pro 64 | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/157tf9/on_gawker_websites_i_need_to_spam_the_back_button/ | {
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"I'd also like to know why this happens, not just for Gawker sites but twitter and a few others",
"What happens when you click on one of their links is you get taken to a proxy page. This proxy page basically acts like a handler for requests. It then passes you on to the relevant page. When you press back on any webpage the browser you use automatically re-enters any data it did the first time around. An example of this is like when you enter data on an internet form. Lets say I'm entering a username and password. I then get somewhere. I then decide to go somewhere else. When I press back to go to the page where I went *after* I entered the data my browser automatically re-enters that same username and password I entered. The same thing is happening on sites like gawker. Personally I feel that it is often a very poor way of handling things and results in forcing people, as you have noticed, to either open a new tab or window, or to mash the back button.",
"I find that right clicking the back arrow and selecting where I need to go is the best way to get out of that loop. It's tedious, having to use the mouse to navigate back, but you gotta do what you gotta do.",
"protip : right click the back button, at least in firefox. opera/chrome probably instead requires that you hold is pressed for a second or so.",
"some web developers think they understand usability better than anyone and so they incorporate clever features like this into their websites, because no one ever uses the back button.",
"Open in new tab. Middle click the link to do that. Middle click the tab to close. On chrome of course.",
"I stopped giving them my page views. So terrible. Let's put an ad on everything, make some of our posts ads, then make them view ads before seeing our ads. Oh, and create sensationalist nonsensical posts to pull views. \n\nIf you're really interested in tech news I've found _URL_0_ to be pretty great. No nonsense. Well a little bit, but it is the internet."
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1xzfw0 | often people say when you get a splinter your body will learn to push it out at some point. how does it happen? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xzfw0/eli5_often_people_say_when_you_get_a_splinter/ | {
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"Your body doesn't learn to push it out, it's just that tissue regrows in such a way that the splinter is eventually moved towards the outside of the body, which eventually results in the splinter emerging from the skin."
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5b2ofw | how do prince rupert's drops work? | I just watched a video on those peculiar glass objects called Prince Rupert's Drops.Amazingly, if only a bit of its tail is clipped of then the entire structure gets demolished in an instant.How does that really happen, I mean what is the physics behind it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5b2ofw/eli5how_do_prince_ruperts_drops_work/ | {
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"Because the glass is rapidly cooled it sets up a state of high residual stress, compressive stress on the surface and tensile stress in the center. This effectively toughens the glass of the head similar to how Gorilla glass is toughened on cell phone screens. The residual compressive stress in the glass resists crack propagation and shattering.\n \nSince the tail is very thin it isn't subject to the differential cooling effect and doesn't set up residual stresses. So it's just ordinary glass. A hammer blow here will shatter it and the crack propagation through the inner tensile stressed material of the head will release the enormous potential energy in the head making it disintegrate.",
"If I were to explain it to a 5 year old, I would say the following: \n\nBecause when the glass cools in water it cools very very quickly, there's a lot of tension and stress still stored up in the \"drop,\" much like a rubber band that's been pulled to as far as it can go and then stuck there. When a little tiny part of the drop is broken, much like cutting off a tiny bit of a rubber band, all that tension goes away, and the whole thing shatters"
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36ghz3 | why/how did smoking become less painful on my throat and lungs over time? | To clarify this is more pertaining to smoking trees than tobacco and cigarettes.
What I mean is, when I first hit a small pipe in high school I coughed my lungs out and it burned like hell. Also, I thought my throat was on fire after a gravity bong hit when I was a novice smoker first beginning.
Now, a couple years later I can clear bongs no problem. Hits that would have left my throat aching for an hour now don't seem to bother me at all. The only time I get the urge/pain to cough is usually after some dabs or the end of a blunt where the smoke gets really hot.
So why/how have I conditioned my throat and lungs do not be in as much pain? I see the same effect with my friends, some don't smoke much and on special occasions when they do hits that don't bother us kill them in regards to pain/coughing fits.
Thanks for the help! And tobacco/tree smokers feel free to share if you've had the same experience. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/36ghz3/eli5_whyhow_did_smoking_become_less_painful_on_my/ | {
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"You destroyed the nerves that were on the surface, and the cilia that are in your lungs that cause coughing when a foreign substance is introduced. Cilia are fine hairs in your lungs that move out mucous. Smoking burns them away. \n\nIf you stop smoking/weed for a length of time, you will regain your lung response to the smoke you are breathing into them. "
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bsm778 | how is a glass of wine everyday good for you? :) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bsm778/eli5_how_is_a_glass_of_wine_everyday_good_for_you/ | {
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"It is NOT healthy at all.\n\nThe thing you heard is only a myth. Take a half aspirine instead.",
"It is not. There is proof to suggest that the antioxidants in wine are good for you. \n\nBut with that said, current consensus is that *any* alcohol is bad for you, and for virtually all drinks, the downsides outweigh any upsides. Drinking is always bad and should be avoided for optimal health."
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37mnem | how does motorcycle rpm and gearing work. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/37mnem/eli5how_does_motorcycle_rpm_and_gearing_work/ | {
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"The RPM of a motorcycle engine as well as how the gearing works, functions on the same principles as any other engine. The whole system is setup slightly different as space is an issue. But the basics are all the same. To answer if your engine is doing the same work at 5k RPM on 2nd gear vs 5th simply, is no, it's not doing the same work. If you ever owned a Bicycle with gears it's the same principle.\n\nAt the low gears, it's super easy to pedal because the rotation is very small. However, you don't output very much energy on the lower gears. At high gears it's the opposite, it's difficult to pedal, but you output much more energy than you're putting in. \n\nBreaking the inertia of a bicycle/motorcycle/car can be a very difficult task, that's why we start at low gears and work up to high gears."
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2fgs6s | what would happen if coke stopped advertising for a year? | Just randomly thought of this in class, but since you'd be hard pressed to find someone who doesn't know about Coke, what would happen if they completely stopped advertising for a year? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fgs6s/eli5_what_would_happen_if_coke_stopped/ | {
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"Pepsi would advertise so much it would drive us all insane!...plus coke advertisements are kind of an American tradition now so Christmas would be sad with no polar bear commercial.",
"I'm assuming you mean advertising as in media (TV, radio, billboards, etc). You should note that Coke advertises EVERYWHERE and you may not even realize it. The soda machine with a giant coke bottle on the front? Glasses with a coke logo at TGIF? That's all advertising too. Even if they stopped all \"ads\", stopped endorsing NASCAR and sporting events, etc, there would still be Coke logo's in your face all over the place.\n\nLets look at 2 scenarios:\n\n1. Coke stops advertising but Pepsi does not: Pepsi's market share increases, as people get bombarded with Pepsi marketing and try it out. However, there's only so far they can go because restaurants with existing Coke equipment aren't going to switch because of TV ads. Coke's revenue decreases more than Pepsi's increases because without advertising, some people will just drink less soda.\n\n2. Both companies agree to stop advertising: People drink less soda in general. Would it offset the amount that they each spend? Who knows, my guess is not because if it did, then the companies would already have stopped advertising.\n\nAdvertising at that level is not about \"making people know about Coke\" it's about having Coke be the first thing you think of when you think \"I want a drink\"\n",
"the coke logo is one of the most recognizable logos in the world, i doubt it would do much to their bottom line in that year. although, i wonder what they would do with the almost 3 billion dollars they spend annually in advertising. ",
"I used to wonder why some companies, like McDonald's and Coke, don't just skip advertising for a while. Maybe only do it every other year. They'll save millions, and it's not like there's any people out there who aren't already familiar with their products.\n\nBut you know, I think they have a very good reason to advertise so much, despite such good brand recognition. There's a reason they'll show you commercials with big burgers up close, and billboards of cold Coke bottles covered in droplets of condensation.\n\nAnd that reason is for impulse buys. They want you to suddenly think \"Hey you know what, I could go for a burger right now\" while you're driving home from work, or \"Yeah some Coke sounds great\" as you're driving to the grocery store. \n\nSo yeah, I believe that if they stopped advertising, they would see a large drop in sales. No, nobody will suddenly not be aware that there is Coke out there, but a lot less people will suddenly buy Cokes on impulse. ",
"In all honesty coke would most likely gain money from not advertising because they are already so advertised without spending any money on it like threw reatraunts and coke machines. Everyone already knows what coke is and society already does most of its advertising anyway. And think about it...who really watches t.v ads or listens to radio commercials anyway. ",
"probably not much. at this point they're so engrained they really need to. it's like hershey. when's the last time you saw an add for the actual chocolate bar?"
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3yhc8f | why does online shopping shipping cost so much more than personally sending packages? | For example; just paid $8 in shipping to (insert photo printing service of choice) and the same size envelope would cost $1 at the post office. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3yhc8f/eli5_why_does_online_shopping_shipping_cost_so/ | {
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"a few examples.\n-amazon (not books)- free under certain conditions, reasonable when not-free. probably has a deal with ups/usps for volume discount.\n-amazon - books - media mail at usps costs $2.65. there is not really a cheaper way to send a book. if you pay less than $4 for a book + shipping the seller is taking a loss.\n-ebay - ebay charges fees based on final bid price not shipping, so some people mark up the shipping to hide costs\n-random other website - for low volume stuff, that $8 includes troubling larry to get up, prepare your package, and drive it to the post office. or the cost of the box +tape + etc.\n\n"
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1w16xt | how can our brains, while sleeping, create images of people/things we've never met or seen before and how can dreams create deja vu/seemingly predict future occurrences? | I find dreams fascinating and mysterious. I've been having these crazy dreams lately and I've also had a few instances where I can't remember if something actually happened or if it was in my dream - Requesting reddit assistance. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1w16xt/eli5_how_can_our_brains_while_sleeping_create/ | {
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"i once watched a report that stated you only dream of people you have already seen at least once. maybe you are not aware of meeting that one person but your subconscious remembers everything.\nthe deja vu thing is easily explained: you experience something and your brain accidentally stores it in the long-term memory instead of the short-term memory. so you think: oops I already experienced that before. Which isn't actually true.",
"Dreams don't actually create déjà vu. That phenomenon is actually created by a slight delay between sensory reception and neural recognition. Basically you witness something via sight, sound, etc, but for whatever reason your brain takes a few extra nanoseconds to process the information, so you feel as though you've experienced it before, and often feel like you can \"predict\" what will happen next, but only as it is actually happening.\n\nAs far as creating entirely new content in dreams - that isn't possible even while awake. All of human creativity is limited to our experiences. Our minds are just able to reassemble these experiences into new combinations. (There are a few exceptions to this, such dealing with things such as scale or color, but those are debatable). "
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94xtej | what are turkeys being pardoned from if they have not done anything? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/94xtej/eli5_what_are_turkeys_being_pardoned_from_if_they/ | {
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"They are \"being pardoned from the sentence of death for being a turkey at thanksgiving\". It is just a silly tradition. "
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3hyt85 | why is computer image recognition so hard? | I talked to someone who worked on the robots that play soccer, and they said the greatest challenge was to get the robots to recognise the ball. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3hyt85/eli5_why_is_computer_image_recognition_so_hard/ | {
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"I know we aren't supposed to post just links, but I don't think there's a better explanation than [this WaitButWhy article](_URL_0_). Scroll down to \"The Road From ANI to AGI\" paragraph.\n\nEdit: For those about to tl;dr - over millions of years of evolution our brains became really good at recognizing objects, because that's what is useful (even necessary) for survival. Computers are very primitive in comparison to our brains, and they can't (yet) teach themselves without any human assistance, so we have to manually \"wire\" them for image recognition.",
"Your biggest problem is recognizing which pixels belong together to one object, and then classifying this object. Life has had over a billion years to develop a semi-decent algorithm for that, which is mostly hardwired into our brain (and because even simple brains are insanely complex and don't work at all like computers, pretty much impossible to reverse engineer)"
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136w1d | intelligence quotient / iq, what exactly is it and what are its criticisms? why is it potentially wrong? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/136w1d/intelligence_quotient_iq_what_exactly_is_it_and/ | {
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"My understanding is IQ is broadly an analytical way of assessing a person's capabilities. It uses a combination of problems, pictures and other tests to assess a person. It is a good measure, but it is not the best indicator for a person's abilities. You may be bad at identifying sequences, but still be good at arriving at conclusions. It also does not take into account a person's emotional intelligence and hence it is argued that this is not a definitive indicator of person's abilities and cannot be used to predict whether or not someone will be successful in life.",
"There are many different kinds of ways humans can demonstrate intelligence, so it's absurd to think that a single number could measure that.\n\nFor example, someone may be a musical genius, but bad at spatial reasoning. Or someone may be excellent at math and spatial reasoning, but horrible that leading others.\n\nThere are also people who think that the IQ tests are culturally biased. If you think that's a load of bunk, take this [fake IQ test](_URL_0_) based on Australian aboriginal society. Now compare it to [this one](_URL_1_) based on westernized norms. Do you see why the former test may do a better job of measuring intelligence in Australian aboriginals than the latter one?",
"IQ is a measure of how 'intelligent' you are compared to the average person your age where you live.\n\nHaving an IQ of 100 by definition means that you are exactly average for your age and area.\n\nA 20 year old and 12 year old writing the same test and marking the exact same answers would get different results. The 12 year old having answered everything the same as the 20 year old would get a higher IQ because older people are expected to get more answers right than children.\n\nSimilarly the test is reclibrated based on region, but this is not a big difference in practice. The result however is that the average IQ in the US is exactly the same as the average IQ in for example Pakistan: 100 because that is how the whole thing is defined.\n\nSome criticisms are based on the age thing. Some children develop faster than other which might lead to having fantastically high IQs as children which later when they reach adulthood go down to only normal 'very smart'.\n\nOther somewhat controversial criticisms are for example about the fact that IQ test are supposedly culturally biased in some way or another.\n\nEven more controversial theories attack the concept of intelligence itself and demand that it be more inclusive. Some people believe that certain other skills and abilities such be seen as forms of intelligence, that for example someone who is not good with numbers or words or spatial reasoning or abstract ideas but is a really good dancer should be considered to be 'intelligent' in that area. While there might be some kernel of a rational and worthwhile argument at the core of this theory it has been pretty much co-opted by people who use it unintelligently like parents who refuse to admit that their child has below average intelligence and insists that he is merely differently intelligent as evident by the fact that he is good at sports.",
"I can't tell you why it's considered inaccurate, but I can give you a few famous cases of incredibly smart individuals with a comparatively low IQ.\n\n[Dr. Richard Feynman](_URL_1_), Nobel Prize winner in physics, had a reported IQ of 125, yet he is widely regarded as one of the smartest minds of his generation, and is known as the creator of modern theories of quantum and sub-atomic computing.\n\n[Dr. James Watson](_URL_2_), Nobel Prize winner in biology, reportedly had an IQ of under 130. Watson is best known as being a co-discoverer of DNA's structure. \n\n[Dr. Francis Crick](_URL_3_), Nobel Prize winner in biology, also reportedly had an IQ under 130, and worked with Dr. Watson on the discovery of DNA's structure.\n\n[Dr. William Shockley](_URL_0_), Nobel Prize winner in physics, was one of three men who first invented the transistor, the circuit that allows the computer on your desk to exist. Also had an IQ under 130.\n\nTo put this in perspective, I have an IQ of roughly 137, yet I'm struggling through my CS program at Purdue University. Even assuming I was able to do my work effectively, I am certainly not as smart as any of the four men listed above. ",
"\"wrong\" is a terrible word to use, it is not \"exact\" in a strict mathematical sense, but it is reliable, in that if you take a test today and another one a week later the scores will be very close. Basically the thing it measures is your ability to take the test. ",
"It means you did well on the IQ test, it doesn't do much more."
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5ojn69 | when someone talks about rendering a video, or an animation, what does that mean? and how would not rendering it affect it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5ojn69/eli5_when_someone_talks_about_rendering_a_video/ | {
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"Rendering means having a machine draw each frame (picture) used in the video. Not rendering it means it would be blank.",
"Think of \"rendering\" as a painter painting a still image. In an animation/video, the computer renders/paints each frame of the video.\n\nIf you do not render it, it would not exist.",
"Let's compare video editing to building a car.\n\nSo you're editing your video, but really it's a collection of parts. Multiple footage clips, effects like color correction, etc. The computer is able to tell you that \"yes, these parts put together make a car\" but rendering is where the parts actually get put together and consolidated into one piece. It's a little more complicated than that I think, but ELI5. \n\nIf you try to play your video/move your car without rendering, the smoothness really depends on if your computer is strong enough to pick up x amount of parts at the same time. Rendering is like putting some of the car together so it can drive a little smoother.",
"Animation, effects, etc. are a collection of 1000's of frames. It would take forever to make those 1000's of frames manually with the tiny changes in each one think about how simplistic old cartoons are that were done that way. The background scrolls and the character has limited motion. Now, compare to something like a Pixar movie where you see individual hairs move as a character moves, etc. The only way to get that is to create a few key frames and have computers render, or figure out the missing frames in between, to complete the entire action.",
"The other aspect of it is that generally when we think of rendering we are also talking about packaging the video elements into a file that is able to sent and played by others (like a .mov or .mp4). Unlike when you are editing it, these are self contained files with all the parts (footage, effects, sound, titles) baked into each frame so that youtube or whatever can play it. While editing the video, the parts are all being pulled from their locations on the hard drive and the computer processors are temporarily configuring them in a way that you can preview it. Or in the case of an animation the computer is \"drawing\" a model based on what you created. This allows you to make changes and see them instantly since the computer will have to redraw the image again either way (think of how a video game would function). But this takes a lot of computing power and so may play slowly or at a reduced resolution until rendering. Also the file will probably only be usable by that particular animation or editing software. Once you are finished, rendering allows the computer to take all the parts and calculations and \"bake\" it in. Basically, instead of drawing the image it instead is just taking what you as a viewer sees and putting that into a digital video file format. \n\nAnother metaphor might be a simple modeling clay figure. You mold it with your hands into a shape, and you can even still move parts of it around or change its features. Once you are done, you take a picture and now you can go show it to your friend without having to bring a block of clay and tools to do it all over again in a different place. ",
"Rendering takes all of the different assets that may be in a video (clips, audio, etc.) and orders them and is more or less a set of instructions...I.E. \"draw a pixel at this location with this color and play a sound\" instead of \"find the sound and video assets in storage, put it in RAM, run calculations on it THEN draw on screen/play sound.\"\n\nVideogames, conversely (for further illustration), are rendered at runtime. Since the character could be anywhere on the screen, particle effects could or could not need to be drawn on the screen, sounds could be true or false, obviously it's not going to be pre-rendered because we don't know what's going to happen yet! \n\nThats why you need a good graphics processor for gaming and video rendering, and why you don't need much processing at all for playing even 4k movies.",
"When speaking in terms of complex 3D animation. There's no way that a computer would be able to process an animation in real time by drawing and manipulating every object in the scene. Rendering is basically just going through each frame of a scene, waiting for it to load, then taking a screenshot. Then you just have a collection of 2D frames, which are far less flexible to manipulate but are much easier for a computer to play back in real time than true 3D, since you're trashing all of the 3rd dimension information as well as lighting, shadows & reflection information, which are some of the most CPU intensive parts of producing a good looking scene.",
"Rendering a video and rendering an animation are two completely different things. To produce a 3-D animated movie, you actually have to do both.\n\nRendering an animation is taking the 3-D scene the artist works with, and computing what the end result would look like. The artist isn't working with the whole thing, they are often using a simplistic lighting model and the final render actually traces out paths of light and how they reflect and refract and absorb across complex objects. Oftentimes there are also physical simulations being rendered. Animators don't model what water looks like, they just have a water simulation that needs to be processed by the computer to figure out what the water should be doing and what it should look like. \n\n_URL_0_\nThis video is an example of what artists actually work with when making the movie (with glitches, obviously). See how the models are simple with no textures and simple lighting? That all gets added in for the final render."
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2pu2xh | why do so many americans blame obama for practically everything? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2pu2xh/eli5_why_do_so_many_americans_blame_obama_for/ | {
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"Uhhhhmm, every president gets blamed for everything. This is not a slight, or a joke, its nearly the main reason they exist.",
"Isn't this true everywhere? I know David Cameron gets blamed for most stuff that goes wrong in the UK.",
"Because most American citizens have very little idea of how their government actually works, and how limited the president's power is, domestically and economically. The president is the most well-known governmental figure, and it's a lot simpler to blame him than to go watch C-SPAN or check voting records and see that it's actually your representatives and senators who are screwing you, in many cases, *specifically* because they know you'll blame Obama for it and they want his approval rating to go down.",
"Most people haven't played Sim City before. I am being serious, playing that game has shown me that you just can't win when you are mayor of a town, everyone wants everything but complain when taxes need to be raised to make money and people start opposing changes. \n\nPlus, the president is basically the scapegoat, they get blamed for almost everything that happens.",
"If you're at the top, it's your fault. If you can't handle it, you shouldn't be at the top.",
" > Uhhhhmm, every president gets blamed for everything. This is not a slight, or a joke, its nearly the main reason they exist.\n\nThis is sadly true. The President of the US is a scapegoat for nearly everything that goes wrong. It's near impossible to please everyone in our country, let alone the world. However, if we take into consideration all the good things he HAS done instead of what he HASN'T done, we can begin to see he ain't half bad. DADT was repealed - Civil Rights progression; The Obama family endorsed Same Sex Marriage - More progression in Civil Rights; The debt crisis has been nearly resolved; Have you seen the gas prices lately?; Oh, the wars have ended and the troops are coming home. There's plenty to be said. Please correct me if I'm wrong, and please, add more. ",
"Over here in Australia, Abbott is blamed meticulously. \n\nIts not just Obama, its every president. Human beings have this tendency to be unique and different, so in every population you will have haters regardless of their class, race religion etc etc.",
"American \"politics\" has become more about making opponents look bad than yourself good. The major political parties in the U.S. are the Democrats and the Republicans, the Republicans try and make the Democrats look bad and the Democrats try and make the republicans look bad. Obama is a very popular Democrat and his character and actions are seen by many as representational of the entire Democratic party.\n\nBy blaming Obama for problems, they are hoping to gain political advantage over the Democrats; I.E. \"Look how BAD the democrats are, our side is clearly the GOOD one, vote for us.\" This only really works because there are only two viable political parties in national politics in the U.S.\n\nThe sad part is, really complex issues that have major impacts on the lives of millions are are boiled down to and decided by this \"THEY BAD, WE CLEARLY NOT AS BAD\" fight.\n\nedit: words",
"Why do so many Americans blame ~~Obama~~ Bush for practically everything?",
"At least on reddit the \"Thanks Obama\" that you see everywhere is usually just a joke.\n\nOther than that there's just a lot of people who disagree with his ideas. I'm not a huge supporter because he hasn't really done much but just my $.02.",
"People like/need a scapegoat. \n\nEverything has random fluctuations and when things go 'down' people like to think it was somebody's fault.\n\nAt least that's how I percieve it.",
"Obama may not be directly responsible for a lot of things, but he is very influential when it comes to laws, etc. Also, being better than Bush could still mean being terrible. Only less terrible than Bush was. ",
"In the Democratic world the leader of the country is essentially the elected fall guy. He/She is the person who takes all of the blame for all situations regardless of who actually caused them. Every single leader in the world is like this. Harper gets the blame on Reddit for every single Canadian problem. People are uneducated in terms of provincial-federal jurisdictions, how courts work, and or how bills are designed. The leader of the country is responsible for all of the bad things and the only good things about that person are international agreements.\n\nWhen you look at George W he instituted a major and important way to which US education works, and the process actually [helped](_URL_0_). Many people criticized it and his legacy should be that he gave Americans a fighting chance in schools.\n\nWhen Bush left office there was the financial crisis. Some felt he caused it because he was the president. But anyone who knows anything about finances knows it takes a decade of financial planning to cause something like this. To that extent the blame went to Bill Clinton, George HW Bush, and Ronald Reagan.\n\nSo as intelligent people the only things we can really blame Bush for are the PATRIOT Act. But we're going to blame it on Obama... because he's President now and he's kept it in place.",
"Because that's the way responsibility works. He's in charge. He gets blamed for the bad things. If he's lucky, he gets credited for the good things.\n\n > Most of the world also seem to agree that hes much better than Bush was.\n\nProving, yet again, Orwell's adage that sanity is not statistical.",
"Well besides the normal everything is the presidents fault aspect. He did heavily support the reform in health insurance which many are upset about and people are upset about executive orders they don't agree with",
"Presidents are like quarterbacks in football. They get way too much credit when something goes right, and way too much blame for when something goes wrong. ",
"President Truman famously said, 'the buck stops here.' Even though Obama isn't responsible for everything bad ever, he is the face of the operation. It's kind of like in sports how the qb or pitcher is credited with his team's success and failure. "
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8015il | why can't another wifi device interfere with another one | Like the phisher wifi device say "Hey, I'm the router, send me your information" as Man in the Middle Attack | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8015il/eli5why_cant_another_wifi_device_interfere_with/ | {
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" > Hey, I'm the router, send me your information\" as Man in the Middle Attack\n\nThey can do exactly this. It is known as an [ARP poisoning attack](_URL_0_) and it is a type of man-in-the-middle. An attacker sends spoofed ARP packets to other machines on the network, causing them to route all packets through the attacker's computer. The attacker will then forward the packets onto the actual gateway, so the connection functions normally but the attacker can intercept and modify the traffic (unless it's seperately encrypted, of course).",
"Because it's encrypted information usually which is essentially useless for your without the necessary certificate ",
"**First of all some terminology just to help you translate my reply:**\n\nSwitch - A device that allows multiple end-point devices like a PC, a printer, phone etc to be connected together. Think of them like a street, with the devices being houses. \"Switches build networks\"\n\nRouter - A device that allows multiple different networks to communicate with each other. Think of them as street intersections. \"Routers join networks together\"\n\nWireless Access Point or WAP - A wireless switch. Think of it as a road for flying cars (sorry weird analogy I know)\n\nA commercial grade \"router\" like you would buy at BestBuy for your house is a combination switch/router/WAP all in one device. Where-as for a business these are typically separate devices.\n\n**Ok so onto the answer:**\n\nShort answer is yes, they actually can interfere with one another. It's only a question of how they do it, and what can they see.\n\nWireless signals are omni-directional, not uni-directional. Think of a Wireless Access Point as a person standing in the middle of a room acting as a kind of traffic cop for peoples conversations. Each person in the room (computer) has to speak to the access point, and the access point passes their message onto another person (computer).\n\nWhen a person goes to talk they are basically shouting so that everyone around can hear. Any device in the area and within range can hear that person shouting. In order to differentiate between peoples shouts, each shout has a different and distinctive pitch of voice (frequency) and since frequencies can overlap each conversation also includes as an associated serial number (MAC address) to identify the person shouting.\n\nThe Wireless Access Point and your computer use this information to sort through which signals it cares about, and which ones it doesn't. When a device receives information that it doesn't care about it is discarded.\n\nThis does however mean that if another Access Point was in the room it would overhear all the conversations going on in the room. Spying on wifi signals is theoretically just that simple. If the hackers WAP was smart enough it could also duplicate or spoof the serial number of the other access point or computer and send false signals back to those devices.\n\nThe way you get around this is through encryption. That passcode that you have on your wifi encrypts the packets being sent between the PC and the WAP so that another access point can't read them. It would be like standing in a room and listening into a conversion in a language you don't understand. Sure you can listen in but it would just be a bunch of gobbledygook to you.\n\nA common attack related to this would be to setup a fake access point that broadcasts a spoofed SSID (wireless name) and make people connect to it. You would be otherwise unaware that you are connected to the wrong network. That WAP then passes on your information to the internet as the normal WAP would, but without you knowing that they are looking at all your internet traffic in the process.\n\nNow keep in mind in industry we have technologies that help protect our users against this sort of thing. But as a home user the most important one is the encryption on your own WAP and the fact that banking websites and such have additional encryption on top of this to help protect you."
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48j5cd | if we could take a snapshot of every atom in the universe, could we effectively predict the future? | So, a very theoretical question considering it's near impossible to complete any part of it.
However, if we could somehow capture the orientation/position/type/energy states/nature of subatomic particles/etc. of every atom in the universe, compiled this information into a supercomputer and ran it in some sort of physics emulator, could it track the positions of where the atoms will end up based on their surrounding atoms, current momentum, etc (assuming our universe isn't effected by something outside of it)? Basically, are atoms predictable?
To my understanding, even though the logic would be difficult beyond belief, I think that this *would* be possible. And if so, a fast enough computer (technology we probably won't ever be able to/need to create) should be able to run the simulation of the newly captured world at an accelerated pace, allowing us to literally see into the future. I can't really wrap my mind around the concept of accelerating time though, and there are most likely properties of physics which we don't even know exist, so I have my doubts. There are a lot of 'ifs' in this problem..
Thoughts? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/48j5cd/eli5_if_we_could_take_a_snapshot_of_every_atom_in/ | {
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"Quantum Mechanics at least suggest, if not prove, that there may be an element of inherent randomness that cannot be eliminated. If that is the case, then it is certainly at least plausible that there is some degree of unpredictability that also cannot be eliminated in macroscopic events.",
"A computer simulating the universe would also have to simulate itself, simulating itself, simulating itself... You see where this is going. It's a logical no-go",
"Maybe. This ideal is often referred to as the \"laplacian theory of deterministic predictability\", or \"Laplace's Demon\". In 1814 Laplace was the first to propose this idea that now seems intuitive to us that with sufficient information we can understand the outcome of any system, and that the universe is just another system. \n\nYou can read about the objections to this \"theory\" on the wikipedia page:\n\n_URL_0_",
"In your premise, yes we probably could.\n\nHowever, your premise is inherently impossible. We cannot ever know the position **and** velocity of an atom."
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3jbep7 | why are males naturally attractive without make-up? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3jbep7/eli5_why_are_males_naturally_attractive_without/ | {
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"Because we are conditioned to believe that girls need make up to be attractive, not to mention that women have used make up for a long time creating a \"norm\"",
"They aren't. Most men would look better with a bit of makeup. It's just not our cultural norm.",
"I love a woman who is naturally beautiful, without makeup. Somebody who doesn't need makeup and knows it. That's a keeper.",
"In. Lot of ways men and women are attractive for different reasons, on a basic animal level so to speak. Men's attractivness often relies on their strength, or their available resources (think of fit, or or with lots of money). On the other hand, women are attractive based on ability to bear and raise young. If a woman appears healthy they seem more suitable for child raising. Things like healthy skin (which shows overall body health), and youth makes, at least from an anamalistic level, more attractive. Thus makeup becomes more important for women. To attempt to portray both of these.",
"The same could be asked about their nails. You'll rarely see a guy getting a mani/pedi, but they always have the best feet."
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25fvb5 | in traffic, why do cyclists by default have to use the road instead of the sidewalk? aren't motor vehicles and cyclists a bigger danger to each other than cyclists and pedestrians would be? | Doesn't seem reasonable to me from a risk-reward-perspective.
Edit: I wrote this ELI5 from the perspective of a slow cyclist who is intimidated by cars and would feel much safer on the sidewalk. The regulations- and predictability-argument makes a lot of sense - but when I'm driving on a busy street with 15 km/h I feel EXTREMELY uncomfortable with cars (who might otherwise be driving with 50 km/h) lining up behind me (passing a cyclist still requires you to keep your distance, you can't just squeeze by) | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/25fvb5/eli5_in_traffic_why_do_cyclists_by_default_have/ | {
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" > Bicyclists on a sidewalk or bicycle path incur greater risk than those on the roadway (on average 1.8 times as great), most likely because of blind conflicts at intersections. \n\n\n\n\n[here is a good post about it](_URL_0_)",
"When I ride, I ride on the roads. This is because: \n\n- That's [The Law where I live in the US](_URL_0_), and [where I live in the UK](_URL_3_)\n- I Follow the traffic signs and lanes. I also use hand signals. \n- Pedestrians do not move for you, ever. So why ride where pedestrians are? Also, sidewalks are overall crappy. They [End abruptly](_URL_1_) aren't [always clear or well maintained](_URL_2_) and are sometimes [quite curvy](_URL_4_)\n",
"Bicycles and cars are supposed to follow the same rules, and both drivers and riders are responsible for maintaining situational awareness. This is intended to create a predictable flow.\n\nAs others have mentioned, while there are notions about how best to walk on a sidewalk, there aren't really any rules or regulations. A bike coming up behind a car can make a fairly accurate assumption about what the car is going to do next based on signals used by the car and/or the lane the car is in. Sidewalks are pure chaos. ",
"Visit us in the Netherlands. You would shit bricks. \nBike lanes everywhere :D",
"ELI5 explanation: Cars and bicycles are vehicles. Roads and rules of the roads are designed for vehicles. Sidewalks are designed for people.",
"Apparently you've never seen a pedestrian get hit by a bicyclist.",
"Been told by police that it's perfectly fine riding on the sidewalk.\n\nI'm in LA, and riding the bike on the street is the quickest way to get killed!\n\nI ride about 70 miles a week and every single time there's someone running a red, a speeding semi, or someone in a rush that doesn't bother to look for pedestrians. I don't see the point in being turned into ground beef just because I had the \"Right of Way.\" That's just being blind to the realities of the road.\n\nHell i've seen people going highway speeds into blind corners where there are bike lanes!",
"I've considered riding a bike to work, but people die too often on them for me to be comfortable with it. These bike accidents seem to occur mainly due to drivers having trouble detecting the bikes in time. They are so small compared to other cards or even motor bikes.\n\n\n\nOne idea would be to add a new law saying that you need to slow to 25 mph while bike riders are visible in front of you. Think of them as mobile speed limit signs. This would allow people behind you, who might not see the bike yet, to slow down which would give them more time to react when they do see the bike.",
"\nHere is my opinion:\n\nI think it depends on the city. In a densely populated area with a ton of pedestrians and slow auto traffic bikes belong in the street. \n\nIn more suburban areas with few or no pedestrians (have you been to phoenix?) bikes belong on the side walk. Bikes in the street here are a real hazard because traffic flows at 50mph while bikes travek at 10-15. It is much safer for all if the cyclist is on the sidewalk and use cross walks at intersections. Its awkward as a car when you try to turn right but then have to wait because a bicycle is coming up from behind about to pass you on your right. Its quite dangerous."
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4twh57 | why is the taste/smell of licorice so polarizing? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4twh57/eli5_why_is_the_tastesmell_of_licorice_so/ | {
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"This is the same with most bitter foods like coffee and beer. People have an inherent disgust for things bitter and you have to learn that something bitter is good. After you have related the bitter taste of licorice with the sweet taste, or the bitter taste of beer with alcohol you start ignoring the bitter taste in these foods."
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62dk1r | how does all dna of a fully grown human fit in a baby? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/62dk1r/eli5how_does_all_dna_of_a_fully_grown_human_fit/ | {
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"DNA isn't very big.\n\nAll of your DNA fits in a single cell.\n\nMost all of your cells have all of your DNA.\n\n_URL_0_",
"It's better than that -- all the DNA fits in almost every one of the trillion cells in a human body! How? Because DNA Is written extremely small, using just a tiny molecule (an amino acid) to represent each \"letter\" of the information. And DNA takes the shape of a long string of such \"letters\" which is all folded up.",
"DNA fits in cells, and so it fits just as easily inside the cells of a baby as an adult.\n\nIn terms of relative size, there's no real connection. It's sort of like asking how the blue prints for a skyscraper can fit in the architect's office."
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cuwqii | why can't dental crowns be whitened/have something placed over them to make them whiter? | I've had crowns on all of my top front teeth and they absolutely look awful. My dentist picked an awfully discolored yellow for my crowns, and the only way to fix them is by spending well over $5,000 to have them all replaced. Why hasn't someone been able to create something to make crowns whiter or something that you can mold over the crowns to make them look whiter? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/cuwqii/eli5why_cant_dental_crowns_be_whitenedhave/ | {
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"Crowns are made of non-porous material that is very, very hard. They don't discolor or stain, so it's uncommon for them to need to be whitened. Crowns are matched to your natural teeth colour, so if you plan on bleaching your teeth, you should bleach them prior to the crowns being colour-matched, or let the dentist know about your plans so they can take that into account (none of which helps you now). \n\nYou cannot mold something over crowns because that will alter the shape and function of your teeth, which could create a lot of problems, from misaligned bite to sores to crowns breaking or coming off. But mostly things just don't stick to crown material very well. You also probably don't want thick, fake-looking teeth. \n\nYou should ask your dentist what colour he selected for the crowns and ask him to double-check that the lab made the crown with the correct colour. If the lab messed up, they should be willing to remake the crowns and your dentist should be willing to put in the correct ones for you.\n\nIf everything was ordered correctly, you could look into \"clip on\" veneers if they're very bothersome. Which is basically temporary veneer, kind of like invisilign but opaque. \n\nAlso, be aware that natural teeth aren't super white -- I believe the average natural tooth colour is A3, which is substantially yellowed. Blindingly white teeth are all achieved artificially.",
"Ug nothing to add except the state of dentistry seems appalling to me. Like, why don’t we have paint on enamel replacement/supplements? Why don’t we have near-invisible “patching”? Like why is it when the tiniest thing goes wrong the first instinct seems to be “let’s bring your tooth to a stump, and put a crown on it - which will need to be replaced in a few years and fuck up your bite, and when your bite is fucked up we’ll just put more crowns on the surrounding teeth!”",
"Crowns and Veneers are made out of specific materials. Your most common options are; Porcelain fused to metal, Lithium Disilicate, Porcelain fused to Lithium Disilicate, Zirconia, and Porcelain fused to zirconia. There are more materials available but these are the most common. And they all have a common attribute, they are made from glass or metal oxides. They are impermeable. \n\n\n\nThink of your glassware at home. How can you color it? By putting glass based colored powders on it and firing it in an oven. It's a lot easier to bake the color into the ceramic while building it, rather than masking the color out.\n\n\n\nOften a Dental Laboratory will error toward making crowns lighter, because it is much much easier to make them darker with an additional firing of color. But making crowns that are finished, lighter, is almost never an option. It involves cutting away the porcelain and rebuilding in a different color. Which the lab would call a REMAKE, but often redoing from start can be easier depending on how much modification is needed.\n\n\n\nIf your dentist delivered your crowns or veneers and you thought they were too dark, you should have let them know, and then stood your ground. They would of course tried to talk you out of a remake, but you can totally refuse to have them bonded. \n\n\n\nCould you send me a picture in a message of your teeth? I can give my honest opinion.\n\nTooth colors in the dental field from light to dark go BL1, BL2, BL3, BL4, B1, A1, B2, A2, etc....\n\nThe most common color used and the most natural is an A1, and maybe a bit brighter.\n\nWhat we see in the USA a lot is people want toilet bowl white teeth. Teeth brighter than BL1. \n\nSo often the patient is talked out of such an unnatural selection and talked into a BL4, and the patient feels it is yellow and dark, even though it is far from it.\n\nWould love to see your smile and let you know what I think."
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5lq7a5 | how do some websites offer free returns on unwanted goods? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5lq7a5/eli5_how_do_some_websites_offer_free_returns_on/ | {
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"Some of it is about price. Whether that comes from charging the customer more, or getting the goods cheaper. Some websites (such as Amazon) have stipulations about free returns depending on who you purchased from or what good it is, unless you pay for Prime, so it isn't actually free. And of course, there are always stipulations about the condition of the item when returned. For example, a fragrance has to be in the original cellophane. So they may eat the cost of return shipping but they get a sellable good back.\n\nFinally, it's about a commitment to quality and a willingness to stand by their products, even if it costs them a bit. A site selling legitimate goods (as opposed to counterfeits, tampered or with undisclosed flaws or damage) seems, on average, more likely to offer free returns as they have confidence that the buyer will be satisfied with their genuine article and its condition upon arrival.",
"It's a cost retailers bake into their business model, and it's a trade off for customers not having physical ability to try on or examine a product. So they might pay shipping on a returned good 1/10 of time but that's still cheaper than maintaining a physical network of stores, or more stores, or stores with much more additional inventory and staff to cover distributed demand. And the lack of risk to customers boosts sales substantially. Plus, online retailers have reduced rates negotiated with shoppers so they aren't paying what you or I would to ship a similar package -- Zappos might pay $2 for what would cost us $10."
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5bwyv2 | posting for a friend, "so color is just a specific reflection of light, correct? would that mean that a planet under another star (ex. krypton and it's red sun) would have completely different colors?" | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5bwyv2/eli5_posting_for_a_friend_so_color_is_just_a/ | {
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"No, not completely. The colour of an object is depending on what light it reflect but our eyes can only see colours within certain wavelengths. That doesn't change on another planet. Certainly a different colour from a light source changes the colour you see from an object but that can be shown on Earth no need to go to another planet. A dark room for photo development for instance is lit normally by red light. That makes the objects seem red because the only wavelengths of visible light is red so only that is getting reflected. If the sun only gave off light in a narrow wavelength then it would change our perception of things.",
"Color is not a specific reflection of light per se, but rather a specific *wavelength* of light. When light hits an object that object will absorb most of it and reflect some of it. This reflection is what we see and label as it's \"color\". If we go to a different planet where the star is purple, the objects would have a purple hue due to the ambient light, but that wouldnt change the specific wavelengths these objects reflect. Green things would look the same as a green thing on earth in a room lit by a purple light.",
"A very red sun would make it more difficult to see colours but the human eye is very good at adapting to different lighting conditions. For example, we can see colours quite well by candle light even though the flame is only about 1500K compared to our sun's 6000K. Modern digital cameras do a reasonable job of automatically choosing a colour temperature too; pro cameras can set colour temperature manually.\n\nThe key is that objects at a particular temperature give off a range of colours so even if \"Krypton and it's Red Sun\" had primarily red light, there would still be some green and blue light. The graph showing colour intensity at different frequencies looks like a bell curve with intensity tapering off only slowly for colours/wavelengths away from the central colour.",
"We evolved eyes suited for the light wavelengths produced by our sun. Things might appear blander under another planet's sun, due to the absence of some color we are used to. Or perhaps so obscenely blue and bright that our eyes and skin burn.\n\nBut it wouldn't make colors that couldn't be seen in a computer monitor or printer paper under a white (= all colors mixed) fluorescent light. It wouldn't add exotic new pigments to our eyes to let us see a different set of wavelengths.\n\nLook up ultramarine for a color that might appear shocking to be displayed on your monitor. It's so unnatural. But that's just because real stuff that makes it is so rare, it's still just a particular tingling of your existing photoreceptors."
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5wie8d | why is an accounting firm responsible for the academy award envelopes? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5wie8d/eli5why_is_an_accounting_firm_responsible_for_the/ | {
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"Tabulating vote data, ensuring its accuracy, and security from disclosure are all things that fall under the realm of accounting/auditing."
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3kjx1m | why is a viral disease, cat leukemia, named as a cancer type? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3kjx1m/eli5_why_is_a_viral_disease_cat_leukemia_named_as/ | {
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"This virus causes the cats to get this type of cancer.\n\nJust like some strains of HPV result in cervical/penile (and throat) cancer in humans, some viruses will integrate into the genome of some of your cells and cause them to turn cancerous.",
"Cancer isn't one disease is a catch-all term for a pile of diseases that make cells grow out of control. There are lots of cancers that can be caused or at least correlate with viral infections. In humans HPV (human papillomavirus) Is credited with an increased risk of cervical cancers for instance. "
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4yx3o5 | how would we know how much *successful* voting fraud is happening, if by definition successful attempts at fraud go undetected? | The number of prosecuted and convicted cases of voter fraud is demonstrably low, but could it be that these cases are the minority of fraud? When we collect statistics about how much fraud is happening, how do we know how much is happening *that we don't know about*?
I'm not saying that there is or there isn't a lot of undetected fraud, but I don't understand how we could find out how much there is. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4yx3o5/eli5_how_would_we_know_how_much_successful_voting/ | {
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"This is a bit like Russel's Teapot--it's very difficult if not impossible to prove that there *isn't* a teapot floating around somewhere between Mars and Earth. It's more useful to focus on the fact there is no evidence to suggest that there *is*.\n\nThere are many ways we could detect large-scale in-person voter fraud if it existed. When someone votes, the fact that they voted is recorded. (Unlike in some countries, their ballot is a secret; it's that they showed up to vote that is recorded.) If fraudsters frequently impersonated registered voters, then two things would happen: when that genuine voter comes to the polling place, it will be discovered that someone has already voted in their name. And looking back at the voting records, which are public, we would find that the records reflect more frequent voting than the registered voter claims.\n\nBoth events are relatively easy to test. Any loser in an election has an incentive to investigate this, and it would be a scoop for any news organization, and both have the means to do so. Yet we do not find them occurring often, in fact rarely ever."
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1eiu53 | why do i get automated phone calls that promptly hang up? | Why would a company want to call and hang up?
I've been getting phone calls that hang up as soon as I answer. When I call the number back the line goes dead. I'm assuming these are automated. I looked up the number and it's from my ISP. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1eiu53/eli5_why_do_i_get_automated_phone_calls_that/ | {
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"Assuming that you don't owe the ISP money, there's a good chance that the person making the calls on the other end is a machine. If you pick up, AND the operator isn't on another call, the machine will connect you two. \n\nOr, it could be that the operator on the other end has to log a certain number of calls a day, and hanging up automatically allows them to say that you weren't answering. That makes the lack of resolution your fault and not theirs. Plus, it allows them to knock out more calls per day. \n\nIt could be happening because someone signed up for internet service and gave the ISP your number instead of their own, intending not to pay for the service. ",
"As I understand it these companies call multiple lines at once, and the first to pick up cuts all of the others of. You're one of the ones who gets cut off. If you know the company responsible then report them for cold calling.",
"According to [unca Cecil](_URL_0_) it could be line testing of some sort.",
"I believe they're called 'robocalls' and they're done to see if your number is a live line, in which case your number is sold to spammers",
"the same thing was happening to me. some time later i noticed that some extra money was being added to my phone bill every month--some company was charging me for these calls and getting paid by the phone company. they must be masking their phone number. you should destroy your phone immediately and get a new phone number unless you want to be stuck footing the bill",
"Some companies use auto diallers to call you then if you pick up transfer you to a human, if there are no available humans the machine hangs up.",
"I get many of those too. After about 15 minutes I usually get a telemarketer calling me.\n\nThey have a long list of numbers to call, and can't waste time risking people won't answer. So the computer goes on and calls a block of numbers. If they answer, they are marked as \"available\" and as soon as someone is free, they call you again to sell you stuff.",
"Telemarketing -- They will call thousands of phones at once, and get a few bites. But they don't have enough operators to serve you all at once, so the dialing system (on their end) hangs up if it can't connect you.\n\nIf you have an equivalent of a \"telephone preference service\" in your country, consider registering for that.",
"[Please read the FAQ and forums at _URL_0_!](http://_URL_0_) where you can search the number robocalling you and potentially find your answer.\n\nBriefly (probably with an error or two), one operator in the US buys 30,000 - 60,000 numbers, set up their own telco exchange, robocalling out of Belize spoofing the caller id. As a telco they earn a fee from network switch interconnect reciprocity. That's right, they earn money by the act of calling. They also operate several telemarketing call centers that you are sometimes redirected to when you answer; the product is irrelevant (duct cleaning, Google SEO, Amex), if some fool signs up they just earn more free money. This is why the human voice can be really rude to you or just hang up, you are irrelevant to them as they've already earned money from you answering.\n\nThe 800notes site, and another linked there that I forget the name of, has a long description on the (ill)legality, previous state government litigation, and extreme difficulties of prosecuting these scum."
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4159wn | why is the lesbian/gay/transgender community referred to with so many different acronyms, many of which are long and confusing? | Also, who decides these acronyms? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4159wn/eli5why_is_the_lesbiangaytransgender_community/ | {
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"Organizations focusing on inclusiveness, but also trying to respect individual differences. Thus: gay - > gay & lesbian - > gay & lesbian & bi - > lesbian & gay & bi & trans - > etc.\n\nUnfortunately there is no single term that seems to encompass all of these, so they end up using a long list of words, which is then so long that they turn it into an acronym.",
"Individuals don't decide these terms. We in the community are just as confused as everyone else sometimes. \"Oh, so that's what we're calling ourselves now.... okay\" \n\nAny marginalized community has smaller groups in it that are further marginalized by that community and society at large. They get double hate. I know some gay people that have said horrible things about transgender people and bisexuals. There comes a point where the group says, \"We shouldn't hate on ourselves\". Subgroups start getting more recognized. This leads to new terminology and respect for the subgroup and redefinition/fragmentation of the group name at large. Initially, it causes confusion for everyone. Utimately, it leads to positive visibility, inclusion, and understanding. This what most people want.",
"There isn't a committee or something that decides these terms. They just kind of evolve over time.\n\nThere isn't really a single community - there are *many* different communities, some of them very different from each other, who are brought together by common needs and interests. And because what constitutes *\"common needs and interests\"* is subjective, who exactly is or should be included in this acronym depends on who an when you ask.\n\nBack in the 40's and 50's, the word \"gay\" tended to be used alone. But this term was overwhelmingly associated with men, and in the 60's and 70's women fighting for a more visible presence in the movement started using the term \"Gay and Lesbian\" to refer to all non-heterosexual people.\n\nIn the 90's bi and trans people fighting for recognition started to become more visible, and Bisexual and Transgender were added to the list - giving us the acronym GLBT. In the early 2000's this got reordered to LGBT.\n\nBut this term is still evolving. And a big problem with an acronym that tries to list every group of people being included in it, is that it implicitly excludes anyone *not* specifically listed. Are asexual people part of this conglomerate community? What about intersex people? Poly folk? The BDSM community? What about people from other cultures, who see their identities as similar to but distinct from the social categories that have evolved in the US - e.g., Hijra?\n\nThe acronym GSM (Gender and Sexual Minorities) seems to be gaining traction as an alternative. Because it doesn't list every group of people included, it can get the general idea across without getting excessively long. But there are concerns that this will lead to the marginalization of minority groups within the community - that GSM will become effectively synonymous with \"Gay\", putting us in a situation similar to where we started in the 50's."
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4110pp | why do people lose their senses of hearing and sight, but not their sense of touch, taste, or smell? | Do people not lose their sense of touch, smell, or taste? Or if they do, how does it happen and what are the effects? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4110pp/eli5_why_do_people_lose_their_senses_of_hearing/ | {
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"People can also lose their sense of taste and smell...you are just a lot less likely to notice them.\n\nPeople also can lose there sense of touch over part of their bodies, but there are not a lot of neurological disorders to totally remove touch...at least not without also killing you.",
"On the contrary, We certainly lose our sense of touch, taste and smell as we age. Part of the challenge of being a caregiver for an elderly person is to encourage them to maintain a good calorie intake while the food tastes and smells more and more bland. \n\nElderly people are at risk of burns and skin injuries due to a lessened sense of touch. Even an electric heating pad can cause major burns in the elderly due to lack of pain perception."
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32mmx0 | why didn't other european powers shut down hitler as soon as he violated the versailles treaty? | As I understand it, the treaty disarmed Germany and forbid militarization. This being so, it seems like other countries could have swooped in and stopped Germany when it was at like 10% military power and on the rise rather than waiting until they got to ~100%. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/32mmx0/eli5_why_didnt_other_european_powers_shut_down/ | {
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"That would require mobilization of troops and resources that many European powers just didn't have. World War I decimated many European countries in manpower, resources and financially and the Great Depression didn't help any.\n\nNot to mention that many politicians wanted to avoid war because it would have been detrimental to their political career.",
"Because of WWI. It was called the \"war to end all wars\" and the countries involved lost so many people, so many towns and cities that there was an extreme reluctance to entering another war. Until Hitler invaded France, there was a feeling that if they just appeased him enough and gave him the Sudetenland and Austria and Poland, that there would be an end to his conquests. In retrospect, it was obviously foolish, but this was the prevailing sentiment in Europe at the time. The first war was that devastating that people were willing to ignore the evidence right in front of their faces. Anything to avoid another war. There were some loud voices calling the West to stop him, such as Churchill, but they didn't gain enough traction until it was too late.",
"Because the European powers:\n\n* Were terrified of another war after WWI\n* Agreed that the Versailles Treaty was too harsh on Germany and was willing to let Germany bend it bit by bit\n* Thought that Hitler was a reasonable man and would stop once he gets his bid to please the people in Germany\n* Did not want to be the \"leader\" who threatened world peace and thought that other countries would stop Germany\n",
"How come a plane full of people couldn't stop 7 guys with box cutters? How about in a checkout line when someone freaks out? Everyone shuts up, or pretends not to notice. The fact is, crazy people rule the world because humans are pack animals, like dogs. We're meant to follow leaders, unlike cats."
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ashwlm | how is netflix able to provide seemingly perfect subtitles to basically every show/movie on their platform and what allows them to do this so well? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ashwlm/eli5_how_is_netflix_able_to_provide_seemingly/ | {
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"The people that make the show or movie write down the subtitles, from the script. They package that as a subtitle file inside the video file, and Netflix opens that up to show it to you if you enable subtitles.",
"When a show is delivered to Netflix it must conform to their specifications, including subtitles. Netflix is not generating these files. \n\n_URL_0_"
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mbbe8 | how does venture capitalism work? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/mbbe8/eli5_how_does_venture_capitalism_work/ | {
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"On one end, there are the big money funds. Some groups that have tons of money. Enough that they've already put a lot into traditional stocks and bonds and money market stuff. Now they want to take some more and put it in a different area: new companies that aren't on the stock market yet.\n\nOn the other end, there are the entrepreneurs. These guys want to start a new company or maybe they have already started it and it's humming along. Either way, starting and growing a young business is hard. It's hard to make stuff without hiring people and it's hard to pay your hires if you haven't already made and sold the stuff. If you just had a bunch of money to start with, it would be a lot easier to get the ball rolling and make something great.\n\nIn order to bridge the gap between the funds and the entrepreneurs, the big money funds hire money managers. Those are the VCs. The VCs travel around looking for new companies that would be able grow in value by a large amount if they had a cash injection to kick it off. (There are also VCs who use their own money rather than simply representing a fund. That type of VC is traditionally called an \"angel investor\".)\n\nIf the VCs find a company they really like, they sit down with the company founders and hammer out a deal. There are lots of options and variations and details in VC deals, but usually it goes something like this:\n\n > Lets argue for a long time about how much the company is currently worth. It's really hard to pin that down because your aren't making any money right now, but there's a lot of potential. OK, we all agree it's currently worth about $10 million? How about we put an additional $10 million in cash into the company? Then it will be worth $20 million and we'll both agree that moving forward 50% of the value of the company belongs to you and 50% belongs to us. Sounds fair? Hopefully, together we'll be able to use that extra $10 million to grow this company to $200 million in about 5 years or so. That would be awesome.\n\nThat would be the most straight-forward VC deal ever. Real deals have lots of details covering all of the possible events that could happen to the company. But, the general theme is that if the company takes off, gets bought by Google, has a big stock market IPO, or whatever, the fund that the VCs represent gets their share of the earnings.\n",
"On one end, there are the big money funds. Some groups that have tons of money. Enough that they've already put a lot into traditional stocks and bonds and money market stuff. Now they want to take some more and put it in a different area: new companies that aren't on the stock market yet.\n\nOn the other end, there are the entrepreneurs. These guys want to start a new company or maybe they have already started it and it's humming along. Either way, starting and growing a young business is hard. It's hard to make stuff without hiring people and it's hard to pay your hires if you haven't already made and sold the stuff. If you just had a bunch of money to start with, it would be a lot easier to get the ball rolling and make something great.\n\nIn order to bridge the gap between the funds and the entrepreneurs, the big money funds hire money managers. Those are the VCs. The VCs travel around looking for new companies that would be able grow in value by a large amount if they had a cash injection to kick it off. (There are also VCs who use their own money rather than simply representing a fund. That type of VC is traditionally called an \"angel investor\".)\n\nIf the VCs find a company they really like, they sit down with the company founders and hammer out a deal. There are lots of options and variations and details in VC deals, but usually it goes something like this:\n\n > Lets argue for a long time about how much the company is currently worth. It's really hard to pin that down because your aren't making any money right now, but there's a lot of potential. OK, we all agree it's currently worth about $10 million? How about we put an additional $10 million in cash into the company? Then it will be worth $20 million and we'll both agree that moving forward 50% of the value of the company belongs to you and 50% belongs to us. Sounds fair? Hopefully, together we'll be able to use that extra $10 million to grow this company to $200 million in about 5 years or so. That would be awesome.\n\nThat would be the most straight-forward VC deal ever. Real deals have lots of details covering all of the possible events that could happen to the company. But, the general theme is that if the company takes off, gets bought by Google, has a big stock market IPO, or whatever, the fund that the VCs represent gets their share of the earnings.\n"
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bmjywd | how do they measure the visual acuity of animals? | You always hear birds and other various animals have better vision than humans. How do we know this and quantify it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bmjywd/eli5_how_do_they_measure_the_visual_acuity_of/ | {
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"One of the oldest way to test it is the following:\n\n1. set up 2 doors: one with food and one without. Put a label on top of each door with black square (door no food) and black square with a single white stripe (door with food).\n2. During the first few times, open both door and let the animal go. After a few times they'll learn that door with white stripe has food.\n3. Close both doors in such a way that the animal can still open it easily, but cannot see through it. Then let the animal go. Since they remember that the one with the stripe has food, they'll pick the door they see the stripe.\n4. Reduce the width of the white stripe. Then let the animal go find the food (repeat this a few times for reliability). Repeat this process until the animal is unable to reliably locate the door with a white stripe. \n\nSource: remember watching a video of eagle vision test (couldn't find it now). The stripe was so small that humans cannot see it with naked eye. The stripe was made using computer-assisted tool."
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1tg4ff | how can north korea have work camps and not get in trouble for it? | How can places like North Korea not get in trouble with United Nations or any sort of world police when they have these innocent people in death camps? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1tg4ff/eli5_how_can_north_korea_have_work_camps_and_not/ | {
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"The UN is mostly toothless, and there's no such thing as \"world police\". \n\nFurther, no one is willing to go up militarily against a nuclear state for fear of starting World War III.",
"Because they're a country. They're not a person and can be arrested by the police. The only way to force another country to do something is either from the threat or application of military or economic action. \n\nNorth Korea has a military 9 million strong and doesn't have an economy to ruin.",
"North Korea would undoubtedly see outside interference as a pretext for war. Nobody wants a conflict with North Korea. They come across as the equivalent of the proverbial bull in a china shop, but the china is nukes."
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bcr935 | who pays for the plane ticket back to your home country if you’re denied entry to a country? | I’m currently watching border control videos on YouTube. When people get denied entry to a country they have to get the first flight back to their home country.
I was wondering who has to pay for that flight. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bcr935/eli5_who_pays_for_the_plane_ticket_back_to_your/ | {
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"The airline that took the person in has to take them back out again, however the airline can then get the money back from individual (or attempt to).",
"The passenger legally has to pay, but the airline is required to take them back no matter what. If the airline will actually get their money is another question.",
"Many countries will not allow you on to an international flight to a foreign (not your native) country without a round trip ticket.",
"It's worth pointing out that when you check in for an international flight, especially from the US, the airline agent will be looking at the basics to make sure you're admitted.\n\nEnsuring you have a passport, valid for the required length of time of the destination, any required visas, etc.\n\nThey can't foresee (or check) every issue that could get you turned away, but they try to catch what they can before you leave home to begin with.\n\nAs passenger data and information sharing (especially amongst allies) gets more advanced, airline agencies are capable of catching more and more \"deny entry flags\" before someone even checks in."
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623qan | why african americans are not given the prefix of their country of origin while european's are? | An example being Solvenian-American and such | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/623qan/eli5why_african_americans_are_not_given_the/ | {
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"Because most of them are descended from slaves, and don't know what country they're originally from, what languages their family originally spoke, etc. Slaves weren't usually permitted to talk about that stuff, families were broken up and sold off so many slaves never knew their parents, non-English/French languages were forbidden.\n\nThat's also why there are Irish-American bars/parades/traditions/pride things, German-American, English-American, etc, but just 'black' for the descendants of slaves. They don't know.",
"Many do not have records of their ancestors' country of origin.\n\nMany have ancestors from numerous different African countries.\n\nSome of the countries in Africa where slaves were usually kidnapped from no longer exist.",
"Because Black Americans who are descendants of slaves usually don't know their family's country of origin. Slave owners and traders were not interested in the ethnic origins of their slaves and kept only the most rudimentary records. Many Black Americans find it impossible to trace their families back more than a few generations.",
"Because most African-Americans are descended from slaves, and thus don't know their country of origin. Even if distinct \"countries\" as we understand them could be said to have existed at the time of the slave trade, detailed records were not kept.\n\nFor more recent immigrants and their descendants, it certainly would not be uncommon to adopt a \"hyphenated\" ethnicity, e.g. Nigerian-Americans or Ethiopian-Americans.",
"In addition to what others have said, at the time that slaves were being taken from Africa, there didn't exist countries in that area in the sense that we think of today - essentially every country that currently exists in western africa is a relatively modern political concept, and many of these countries have complicated mixes of different ethnicities within them.",
"I have previously asked some friends of mine this exact question, because some of them DID know where they came from (generally-ish, at least), but all still wanted to be thought of and called African American or black.\n\n\nThe reasons varied a bit, but could be paraphrased like this: \"Black Americans are their own culture and totally different from African Africans of any type. I'm not one of them, I'm different. I'm not my country of origin, I'm a unique culture that only exists here.\"",
"In addition to this, I've always been interested in the American system of putting a prefix in there at all. I've noticed Americans saying 'I'm Irish' or 'Italian', when in other countries, it's more typical to just say that you're the nationality you were born in.\n\nIs it because America still holds a lot of value over the idea that they're a 'nation of immigrants'? A lot of countries are, but they don't tend to hold onto that idea as much. "
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29d09f | why do dogs drink out of the toilet, even though you give them fresh water? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29d09f/eli5_why_do_dogs_drink_out_of_the_toilet_even/ | {
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"The toilet water is renewed more often than most people refill their dog's bowl. They probably think it tastes better after a fresh flush than in a bowl filled with standing water. \nIf you close the bathroom door and fill their bowl with clean cool water a few times a day they might stop going to the toilet for a drink.",
"As far as the dog's concerned, a source of water is a source of water. All he'll care about is that there's always water there, it's clean (by the dog's standards) and at a convenient head height for drinking. Dogs are also creatures of habit and will keep going back to the same places for food and water just because that's what they're used to doing.\n\nIf a dog's drinking out of the toilet, encourage him to drink from his own bowl by making sure that his bowl is always kept full of fresh water, that it contains enough water for him, that the bowl is always accessible and that it is always in the same place (preferably close to where he eats and/or sleeps). Also, reinforce good behaviour by giving him treats for drinking from his own bowl.",
"For the same reasons that they drink out of mud puddles, and eat carrion if given the chance. It doesnt matter to them. A humans idea of clean or safe is a complete abstraction that dogs dont understand. Also a dogs digestive tract and immune system is WAAAAAYYYYYY more robust than that of a human. My own observation of dogs is that they prefer gross stuff to clean stuff."
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2hcjc6 | what is happening in our heads that allow thousands of people to sing, shout, clap or speak in almost perfect unison? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2hcjc6/eli5_what_is_happening_in_our_heads_that_allow/ | {
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"I haven't been able to find anything completely definitive, but the phenomenon you're talking about is called [entrainment](_URL_0_) (specifically, beat induction), and is similar to how fireflies synchronize their flashes.\n\nThere's a neural deficiency known as [beat deafness](_URL_1_) that prevents people from being able to detect the beat in music. This appears to be caused (in at least some cases) by issues with the left auditory cortex, which is involved in beat detection (as opposed to the right audio cortex, which detects harmonies).\n\nSo the short answer is \"our brains are hard-wired to be able to find beats in music (including that produced by people around us in a crowd), and to coordinate our actions with that beat.\""
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3sis6i | if i drive 5 miles going 40 mph vs. the same 5 miles going 80 mph, will one require more gas than the other? | Assuming all factors are the same & not including acceleration time. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3sis6i/eli5_if_i_drive_5_miles_going_40_mph_vs_the_same/ | {
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"The short answer is that at those speeds yes, air resistance increases and going 80 will take more fuel. If you stick your hand out of the car window when doing both of those speeds you will notice that the air pushes harder on your hand at 80mph. The car engine needs to output more power to hold the speed because the resistance is higher, and thus needs more fuel to do so.\n\nNow going slower using less fuel is not always true. With a modern car the highest fuel efficiency is somewhere around 35-40mph. If for example you did that 5 miles at 5 mph the car would actually use more fuel than at 40 miles per hour. This is because there is some base amount of energy the engine needs to just keep itself running and that becomes a much higher percentage of the total energy used to travel the set distance.",
"Just to summarize some of the comments here. Two main factors affect fuel efficiency at different speeds:\n\n1. Resistance - wind resistance is ~~exponential~~ **quadratic** with speed, so the faster you go, the more wind resistance there will be\n\n2. Driving inside your powerbelt: \nThis is the region where your engine is most efficient. Your car runs best when in the top gear with RPMs in the power belt. For most cars, this is 45-55 mph. A hybrid takes advantage of this by always running a small engine within its power-belt and using it to make electricity then converting the electricity back into moving your car forward. \n\nIn general, a gas car is most efficient at 45-55 mph, which is why they usually have a higher \"highway\" than \"city\" mpg. A hybrid only needs to worry about wind resistance, so its \"city\" mpg is usually higher than \"highway\" (regenerative braking helps here too). "
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2fn91h | what was happening in north america during the bible? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2fn91h/eli5_what_was_happening_in_north_america_during/ | {
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"The guys who wrote the bible weren't aware it existed.\n\nEdit: To clarify for people complaining about the answer:\n\nMost (or possibly all) of the events of the bible did not literally occur, making the story as a whole, fictional. Asking what was happening in North America 'during the bible' is like asking what happened in North America during the events of \"A Game of Thrones\". North America did not exist in either of those fictional universes.",
"Gonna have to be a bit more specific on what PART of the bible's timeline you are talking about. Damn book goes from the beginning of the world to the end.... ",
"_URL_0_ \n_URL_1_\n\nProbably a lot more than is shown there, but the indigenous people did not keep written records, so it's hard to know very much.",
"Natives. Literally.\n\nIf we look at the bible as a semi-historical text, it goes back a few thousand years.\n\nPeople started migrating over the Land Bridge into North America from Asia before that. Meaning that while David fought Goliath, Geronima was chasing the buffalo. While Moses led the Jews out of Egypt, Sacagawea was helping prepare food. While Jesus was sitting at the last supper, Squanto was deciding whether or not to travel to the winter camp.\n\nThe Natives have little written history, and even that which does exist, in drawings and oral history has been destroyed. We can't tell what exactly was happening, but we have a decent idea that the Native Americans were just living their lives. Like the Picts were living their lives, the Japanese were living their's, and the Australians, and Indians, etc.\n\nEdited for political correctness, because apparently English versions of Native Names are racist.",
"Well considering the Bible covers a period of roughly 4000 years, what part of it are you talking about? ",
"Some religious folk (I'm looking at you Mormons!) believe there was a bunch of Jewish descendant there, having wars, writing their own Bible and waiting for Jesus to come down and give them all high fives.\n\nAs mentioned by other comments though, the actual historical record is pretty scant. We have some broad educated guesses but the actual details is anyone's guess.\n\n",
"During the bible, let's say 4000 BC to < 100 AD. North America, not including Mesoamerica, was in the Archaic period where we had bands of natives living in some permanent and semi-permanent villages. The end of the archaic saw larger settlements and public-ceremonial building construction. Mounds and earthworks. By 1000 BC or so to 100 AD was the Woodland period where we started seeing more complex societies, more permanent settlements, and much more mound construction especially in the Southeast and Ohio River valleys. \n \nEdit: I can give more detail if I'm given a smaller region/specific time period to work with. \n",
"The Bible makes no mention of it, since the writers didn't know it existed (this gap is where Mormons make their theology).\n\nHistorically speaking, there were civilizations in the Americas at that time, but we know comparatively little about them as compared to the ancient European or Asian civilizations.",
"The Book of Mormon actually talks about the North/south American tribes exposure to the \"spirit of god.\" The book depicts Jesus visiting the continent after he was crucified and gives a rather large and interesting story of the major tribes the nephittes vs the lamenites. The book ends with the nephittes being destroyed by the lamenites. Then a man by the name of Mormon (I think, or Moroni) hiding it in the ground and many years later it's location was revealed to Joseph smith by god. \n\nSorry for any spelling mistakes and my rather crude summary. I was raised in the lds beliefs. I'm not a Mormon anymore, I honestly got tired of religion and rely on thinking with logic and reasoning, having faith in crazy things is just not my way. I was raised Mormon however, was an interesting book to say the least. (I've been inactive for about 3-4 years so be wary of details and such I've said)\n\nEDIT: Don't down vote me, I'm literally explaining a religion's beliefs I'm not a part of. It's not like I'm preaching.",
"Not to offend this sub, but this question would be better for /r/askhistorians. You're more likely to receive a well sourced answer on a subject like this. ",
"The best answer is, no clue. My people had no written records and everything was oral. Much like early Anglo-Saxon tradition when something really important happened it transformed into a tall tale or a song. A lot of these tales and songs were lost throughout the ages and had to be \"reborn\" into a heaping pile of bullshit that is rather meaningless.\n\nThe thing about early aboriginals was that the Americas were a giant land that had tonnes of huntable wildlife, one of the largest fish reserves in the world, and some reputably bad seasonal weather shifts. Being a nomadic people made a lot of sense. The earliest European settlers in North America couldn't stomach the weather shifts so they'd leave when winter arrived.\n\nYes, there were wars. They were not as plentiful as that of Europe and Asia Minor. Without crops and without real land claims there wasn't much a reason to go to war... unless two tribes were hunting in the same region at the same time.\n\nYes there was trade and yes there was politics. The Iroquis nation split the six nations (Seneca, Cayuga, Onandaga, Tuscara, Oneida, and Mohawk) across modern day Ontario and Quebec. Clearly there was enough of an administration and politics involved for six different tribes to form a confederacy.\n\nA lot of the findings we have of early aboriginals is movement records. They're not fun, and they don't make great stories. The earliest written records we had of aboriginals came from the Vikings who setup shop in North Newfoundland and Labrador only to be expunged by a far more violent and far more war like aboriginal tribe (presumably the Beothuks)."
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xt1ao | /r/darknetplan | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/xt1ao/eli5_rdarknetplan/ | {
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"So websites have names. The place that has all these names is called ICANN. When you type in a website name, ICANN tells you the address for you to go to so you can get to that website. A lot of other fancy stuff happens that makes the information get from one place to another.\n\nThis is good most of the time. Remember a name, get to a website. The big problem is that because all of this information runs through ICANN, among other systems, it's easy to see who was looking for what. That means people can watch what you're doing on the internet. This is important.\n\nNow, say you don't want people to know what you're doing, whether you're talking bad about your government, peddling illegal wares, or just exercising your right to privacy. You need a new way to transfer info without the internet. A darknet will do that. It is an untraceable way to communicate with other over a network.\n\n/r/darknetplan is a just a way for people to organize the best procedure and method of creating this theoretical \"darknet\".\n\nAn alternative option is an easier but less secure method, generally known as an \"undernet\". It's not completely untraceable like the darknet, but still has more anonymity than the normal internet. TOR is an example of this.",
"It's an attempt to set up a delocalised alternative to the internet, where no government or corporation can monitor or shutdown.\n\nWatch [this](_URL_0_) video.",
"the Internet used to be free from government/corporate spying and interference, where people had privacy. but not anymore, so they're making a second Internet that will avoid all of this"
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4vwe4t | what causes baseball pitchers speed to be capped at approximately 105 mph? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4vwe4t/eli5what_causes_baseball_pitchers_speed_to_be/ | {
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"The human factor. We are near the peak of human capability in many aspects as science has helped us get very efficient with training and nutrition. You may see a ball a little bit faster, but you're not going to see a 200 mph fastball until we start using bionics and other tech. Same with running. We see under a 4 minute mile right now, but under a 2 minute mile, that's over 30 mph. We're just not built for that without inventing a human 2.0",
"I recall reading a popular mechanics article about this. One interesting aspect was that the amount of torque needed to throw the ball in excess of 105 mph corresponded roughly to the point where a certain ligament in the elbow would tear. \n\nFor reference:\n_URL_0_",
"Not sure anyone can say that 105mph is the maximum speed, just that pitchers today are approaching a max speed. Eventually someone will come along and toss a ball at 106.\nI think of it the same way as Bolt's 100m time being the \"fastest possible\". It's approaching the fastest, but someone will eventually beat it.",
"just watched a Netflix documentary on fastballs called \"Fastball\". One item to note is today fastballs are measured basically right when they leave the pitchers hand. Back when radar guns first game out and they clocked Nolan Ryan at 100.6 they did the detection 10 feet in front of home plate. Calculating for distance/air resistance/etc it's calculated he threw 110 mph early in his career if measured using today's setup. (The ball is slower by the time it reaches the catchers mitt)\n\nAs for ligaments exploding at 105 he regularly threw 150+ pitches per game.\n\nSo 105 isn't the max, but no one seems to be coming around throwing 120 anytime soon.",
"Not a biologist, but I am a big baseball fan who likes science. To start, I think it would be better to say the cap seemed to be at 103mph - [only four pitchers have been clocked at over 103mph](_URL_0_) and only Chapman above 105mph.[1]\n\nThe cap seems to be the ulnar collateral ligament or the UCL which is in your elbow. Scientists believe that the fastball [puts the UCL right at its breaking point](_URL_1_) and that if somebody was throwing much faster they would break it. \n\nIn fact, we often see power pitchers need to have Tommy John surgery where the UCL is repaired with a ligament from the leg. There are even times where [some pitchers](_URL_2_) with a repaired UCL come back throwing faster than before. \n\nI like your observation that \"there are plenty of smaller build pitchers that can throw very fast.\" It makes me think of Pedro Martinez who threw up to 97mph at 5'10\" or 11\" or Tim Lincecum who was [clocked at 101mph](_URL_0_) at 5'11\". \n\nThough the fastest pitchers of all time have been above average height even if not much so: Chapman is 6'4\", Zumaya is 6'3\", and Nolan Ryan is 6'2\".\n\nIf you'd like to learn more you can watch a great Netflix documentary called Fastball. \n\n**tl/dr**: The UCL is the limiting factor so we aren't likely to see pitchers throw much faster, even with better nutrition and conditioning.\n\n[1] We have changed the way we've measured fastballs, so we think that Nolan Ryan might have hit 108.1mph in the 70's. \n",
"I find it awesome how for most pitchers the gold standard for a velocity ceiling is exactly 100. A manmade ball with an arbitrary height and distance of mound...and it produced a benchmark of exactly 100 mph for a long time. Thanks a lot Aroldis Chapman."
]
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9lcitd | how are horses taught to respond to the controls of the rider? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/9lcitd/eli5_how_are_horses_taught_to_respond_to_the/ | {
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"Repetition and reward. It's a long process to train a horse, and there are different methods (Western vs English mainly) but it all boils down to repetition and reward. Just like teaching a dog to sit, or a toddler to use the potty.\n\nThanks Pavlov"
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7huyee | how does “i want my lawyer” work when being interrogated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7huyee/eli5_how_does_i_want_my_lawyer_work_when_being/ | {
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"When the police read you your rights (Miranda rights) they tell you that if you do not have a lawyer, that a lawyer will be appointed to you. \n\nYou are also given a phone call, to which you can call your lawyer. Otherwise, the officer/jail will work with you to find/contact your lawyer as they cannot really serve justice without going thru the legal process, which includes you making a statement, etc. \n\nIf you need a lawyer and cannot afford a lawyer, a lawyer is appointed via the public defenders office.\n\nIf you can afford a lawyer, but do not have a lawyer, they will provide you with a phone book, etc, to contact and contract a lawyer. ",
"In the US, the right to remain silent and a request for a lawyer usually go hand and hand. You are basically saying, \"I'm not talking anymore, move on to the next step or release me. \n\nIf you are arrested, you are either released after the arrest, or a bond is set. You don't need a lawyer for either of those things, although a lawyer could argue for reduction or elimination of bail. \n They can also persuade the police to not charge you. If your timing is bad, you can wind up spending a night or two in jail, but that is more about waiting for a judge to set bail than finding a lawyer.\n\nThe lawyer comes into play when:\n\n* you want to talk to the police, but be protected from yourself\n* you want to negotiate with the district attorney\n* you are on trial",
"In the US, your invocation of your right to a lawyer requires the police to stop questioning you until a lawyer is provided.\n\nBecause police know that the lawyer’s advice will be for you to *stop talking no matter what*, asking for a lawyer is ordinarily treated as a de facto exercise of your right to remain silent. When you ask for the lawyer, the interrogation will end. Since you’re no longer being interrogated, there’s no need to go out and find a lawyer for you. By the time your arraignment comes around, you’ll have hired a lawyer or been assigned a public defender. \n\nThere are occasionally exceptions to the above. But that’s the general procedure. ",
"There are a number of possibilities depending on the situation.\n\nIf youre arrested Friday night, you might be in jail until Monday morning, for example, as a judge won't set bail until then. Same with a 3AM arrest, you're likely to be in jail until morning.\n\nHowever, those aren't strictly the same as INTERROGATION-which is the cops asking specifically about specific crimes of which you are suspected.\n\nIf youre arrested for some BS- fighting, for example, you may not need a lawyer at all. If no one presses charges, or if you were caught up in a sweep at a rowdy protest or tossed in the drunk tank, they may just let you walk.\n\nIf not, for most stuff, the cops want you gone. Having prisoners is expensive and a hassle. You'll get all the collect phone calls you want to whoever you want as long as someone will get your dumb ass.\n\nIf you're being interrogated, an attorney is a right you have. It may be a lawyer you call (they have lists) or a public defender. Either way-once you CLEARLY and UNAMBIGUOUSLY ask for a lawyer, the interrogation stops. \n\nYou must also shut up. If you start talking again, at all, you essentially consent to being questioned again.\n\nBasically, cops are mostly interested in processing you and ensuring you get your rights within the law so you can't make a fuss in court. Getting a lawyer isn't hard-if you aren't the subject of a criminal investigation they want you to have one to go away and if you are they'll happily provide one so you don't sue."
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49kq37 | why can't people who are very light in weight donate blood? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/49kq37/eli5_why_cant_people_who_are_very_light_in_weight/ | {
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"Because the medical common \"unit of blood\" represent too large a proportion of their total blood - it would be unsafe for them to donate.",
"they have smaller bodies. Smaller body = less blood. They typically (in the US) take about a pint. That can be too much blood to take from a person if they are too small. \n\nI weigh 180lbs and just so happened to give blood today, and even at 180, giving a pint left me a bit dizzy for a while. I had to sit for a good half hour before i was Ok to walk on my own..",
"So, as someone who is ~105 lbs, it really WOULD be unsafe for me to donate blood?? I've always wondered this because I would like to, but the technical min. weight is 110 I believe....however, I'm just 5lbs short! ",
"The estimated amount of blood in a 180 lb. human is about 1.5 gallons.\n\nA pint is 1/8th a gallon. Which comes out to a little more than 8% if that person's blood. In a smaller person, their reduced blood capacity can cause that to jump to over 15%, in which the body begins to get worried, and takes measures to try to compensate.\n\nIf the person is in perfect perfect health, 15% wouldn't do any lasting damage. They might feel woozy or even pass out for a bit. **Nobody** is expected to be in perfect health though, so they only want people whose percentage will be 10% or less. You might feel light headed for a little bit, but that's as far as it should go."
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2cm80k | twitter reported a q2 loss of $144.6 million. how do they still afford to run a company and attract investors? | Referenced article: _URL_0_ | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2cm80k/eli5_twitter_reported_a_q2_loss_of_1446_million/ | {
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"Investors think they will be very profitable in the future, so they keep investing money, despite it currently operating at a loss. At some point, it becomes necessary to monetarize Twitter, which means (you guessed it) ads.",
"Apparently, they have more than $144.6m, and/or access to more funding/credit. That's how they can continue afford to operate. As for why they attract investors, it's hard to say why, but apparently, they are successful in convincing people with money that they'll generate more of it if they let them use it to build their company. You'd have to ask the particular investors why they think that. ",
"Investing is complicated. There are many different types of companies to invest in. Some companies, like Apple, have lots and lots of money. They are a safe investment, and will will investors money over the long run, but will not fluctuate much. \n\nSome investors are looking for companies that could one day ramp up quickly and reward early investors heavily. Those companies tend to have lots of risk associated with them. In many cases, companies will be funded by Venture Capitalists because the idea is good. It takes a while before such a company can make enough money to actually turn a profit. \n\nThat does not mean the company is making zero dollars in revenue, of course. They are just making less money than they spend to run the company. \n\nSo the key for a company like that is a *trend* of upward moving profits... i.e. they lose less and less every quarter until they actually cross the boundary and start to make money. \n\nWay back when, Amazon was the epitome of this sort of company. People were agog at the number of investor's lining up to buy stock in a company that couldn't turn a profit. Amazon eventually got themselves sorted out. \n\nIn Q1 2014, Twitter made $250M. That's still a lot of money. "
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1xl3fg | github, including what branches, commit and repositories are. | Any and all explanations are greatly appreciated. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1xl3fg/eli5_github_including_what_branches_commit_and/ | {
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"text": [
"GitHub is just a git-based code repository. It's used for maintaining a code base, including distribution and version control. There are a lot of them, but git-based ones are popular these days because they work well.\n\nRepositories are communal places to store code and code changes. They can be free and available to all, or restricted to only certain users with certain abilities.\n\nCommits are pieces of code that users have pushed up (committed) to the repository. These commits are changes to code by a user, published so that all other users can see them\n\nWhen I branch code, I'm taking a version that exists, and creating a new version from it. My new version is going to be a new branch, which keeps your changes separate from mine until I...\n\nMerge the branches. Which means I take your code and combine it with mine, to make a single set of code. This new single set of code can be a new head to the tree, or simply a new head to your individual branch, but it's taking multiple branches and making them one.",
"GitHub is an online place for people to store information. Let's say you and your friends are working on a story, so you start typing it up and you store it online in your own *repository* (just your own little place on the website). You give your friends each the opportunity to set up an account on the website and make it so that they can all make changes.\n\nYou need to have good control over what goes on, though. If you are editing the 3rd paragraph and so is your friend Jeff then you really only want one person to be able to save (\"commit\") their changes. The other person would then have to re-download the data (\"pull\") and compare what is different between their working copy and the copy that's in the repository (diff). Once they have resolved the differences to make sure that their changes make sense with the changes you made they can commit their changes, too. In more formal settings it is likely that two people wouldn't be allowed to work on the same part of the story at the same time anyway. Sometimes, though, you will be working on the 3rd paragraph while Jeff is working on the 18th paragraph and the program is able to combine your changes without any problems (\"merge\").\n\nPerhaps some other guy comes along and sees your story and decides that the story would work better using dinosaurs instead of aliens. Thus, he grabs a copy of the repository (\"clone\") and starts working on his own version (\"branch\"). It starts out as the same but it diverges from there.\n\nAs time goes along perhaps someone sees the story and thinks that there's a change that needs to be put in (perhaps they see a place where you used there instead of their). They can make the change on their own copy then recommend the change to you (\"pull request\").\n\nThroughout the entire process you have the ability to go back and look at any version that has ever been committed to the repository. You can even undo a commit if it broke something (\"revert\").\n\nThis whole process is done through a program called \"Git,\" and GitHub is just one of many places where a repository can be hosted--you can host a Git Repository on your own computer is you know what you're doing. \n\nAll of these uses are a little over-the-top when talking about writing a story, but they become invaluable when working on a programming project with several people. It's important to have everyone working on the same code and it's really nice to have the ability to see who made what changes, especially when a bug pops up that didn't exist before. GitHub is especially useful for open source projects since it lets anyone look through the source code of the project and if someone thinks that the project could be modified for a slightly different use then they can make their own branch without bothering you, then suggest revisions to fix bugs that they happen to come across and fix. "
]
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[],
[]
] |
|
57rts5 | can the body repair a rupture of a spinal disk? | what happenes in the body when you rupture a disk in your spine and can the body repair or heal itself? what can happen if this condition is left untreated? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/57rts5/eli5can_the_body_repair_a_rupture_of_a_spinal_disk/ | {
"a_id": [
"d8ulk6j"
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"score": [
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"text": [
"So I ruptured the disk in my neck. The doctor explained it like this:\n\nThe disk is like a krispy Kreme doughnut. When it ruptures the jam inside spills out. It could split on the inside or on the outside. On the outside is not such a problem. However on the inside it can directly apply pressure to the nerves it surrounds. After a while this jam can 'dry' out and can retract back inside. This is painful for obvious reasons.\n\nNow the non ELI5 bit. See a doctor if you can. If you loose feeling or get pins and needles in a limb see one immediately. This is, according to my doctor 'really bad'. Now I just had extreme pain, we are talking screaming and being taken away in an ambulance high on ketamine bad. The 'jam' was only 2.6mm according to the scans. It has healed but is weaker and occasionally happens again to a less serious degree each time. "
]
} | [] | [] | [
[]
] |
|
5mxjni | why does your body temperature increase when you're nauseous and or vomiting? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5mxjni/eli5_why_does_your_body_temperature_increase_when/ | {
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"dc7250c"
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"text": [
"Body temperature doesn't increase because you're nauseous or vomiting.\n\n It rises so it can kill the intruder, like bacteria. \n\nVomiting happens so the body can get rid of the bacteria. I assume the main reason for vomiting is that the body tries to get rid of the material that has the intruder in it. Like spoiled food.\n\nIt also happens even if you ingest safe substance because the body doesn't know it's safe. "
]
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[]
] |
||
698f5i | why do kids and some adults jump up and down when excited or happy? | [deleted] | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/698f5i/eli5_why_do_kids_and_some_adults_jump_up_and_down/ | {
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"dh4kjbd"
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"text": [
"Have you never done this? Never gotten so excited and filled with energy you just have to move? It's an energy release. We're also social animals and this is a way to express our excitement. \n\nPlus it's good for ventilation, moves the air around."
]
} | [] | [] | [
[]
] |
|
ec8io3 | how are roads on steep cliffs built? | Whenever I am driving through the mountains I always end up on a road going along the middle of a steep cliff and I've never understood how the road crews and engineers built the road on the first place. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ec8io3/eli5how_are_roads_on_steep_cliffs_built/ | {
"a_id": [
"fb9tvhn"
],
"score": [
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"text": [
"Dynamite. I remember going on a hike somewhere in Utah and there was a trail that was originally going to be turned into a road but they just left it unfinished and made it a trail instead. You could see where they drilled the holes and were going to blow the cliffside. It takes a lot of precision to keep it somewhat level and prevent the whole side of the cliff from just crumbling. To level the road, they'll just use all the dirt and small rock debris to make a flat surface, then pour asphalt over it"
]
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[]
] |
|
8skrco | how does 50% sodium salt exist? | As sodium is a fundamental ingredient to the molecular structure of salt with a 1:1 relationship, how does Morton or other salt companies create the same amount of salt but with something like 50% less sodium? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8skrco/eli5_how_does_50_sodium_salt_exist/ | {
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"text": [
"Well since salt is 50% Sodium and 50% Chloride technically speaking all salt is 50% sodium.",
"They displace sodium chloride with potassium chloride. It doesn’t taste exactly the same, which is why light salt tastes a bit strange.\n\nSource: _URL_0_",
"\"Salt\" is the name of a wide variety of compounds. Sodium Chloride is table salt, but other like potassium iodide are also salt.\n\nLow sodium salt is just a salt that uses no or less sodium. ",
"We call NaCl \"salt\" like we call ethanol \"alcohol\"; there are many kinds of both salt and alcohol, but most people are only familiar with a few of them. \n\n50% sodium salt is just regular NaCl mixed with another salt, usually KCl. It's a bit ironic that people without sodium-sensitive medical conditions turn to it for health reasons because KCl can actually be harder to get rid of, especially for diabetics, and can be *more* detrimental to health than NaCl. This is a very common theme; chemistry illiteracy is so rampant that people often run from something relatively harmless to embrace something else that can be worse."
]
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[],
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"https://www.mortonsalt.com/home-product/morton-lite-salt-mixture-2/"
],
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|
3s6vio | how does preloading games on apps such as steam work? | I understand that it gives you a download before the game is released so you can play as soon as it is released. I don't understand how once you have the game files it can still restrict you from playing. Is there another final component to download or..? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3s6vio/eli5_how_does_preloading_games_on_apps_such_as/ | {
"a_id": [
"cwulsgj"
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"text": [
"Two ways:\n\n1. The game files are encrypted, and the decryption key is given only when the game is released.\n\n2. Most of the game files are assets such as music, textures and models. The actual game executable is relatively small. Preloading downloads these assets but not the executable."
]
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[]
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|
bxgaim | when you google a certain store or restaurant and it gives you a bar chart of peak times, where does the data come from? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bxgaim/eli5_when_you_google_a_certain_store_or/ | {
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"When you have Google Maps, you can turn on location tracking to help Google learn certain tasks. For example, it will learn where your home and work are, and what route you usually take to get there, so then it will send you a message when it's time for you to leave for work based on current traffic. \n\nWhen you have location tracking enabled, Google can use GPS to determine that you're probably at a particular store or restaurant if you linger in that location for a while. So if Google notices that around 6pm, not many phones are announcing their location at a particular restaurant, but at 7pm, a lot are, then at 8pm, not many are pinging again, they can surmise that 6pm and 8pm aren't very busy, but 7pm is. \n\nRepeat that over weeks and weeks and they can build a pretty good idea of how busy a restaurant or store will be at any given time.\n\nIf you use google Maps, you can even look at where Google thinks/knows you have been. Go to Menu > Your Timeline and it will show a history if you have location tracking enabled. For instance,[ here's some of my tracking from yesterday.](_URL_0_) I didn't have to do anything or even confirm I was at those places. Google Maps just knew from my GPS.",
"If you have an android device or Google maps, they track your location 24/7. \n\nIf you're curious, Google lets you sign in and see the data they collected on their \"Google Maps Timeline\": [_URL_0_](_URL_0_) \n\nIt's incredible. Time-stamped, accurate to a few feet, going back YEARS. \n\nSo, when you see those peak usage times, that's essentially a count of android phones inside the store at certain times.\n\nThey do something similar for the Google Maps traffic. Track the speed of phones, and you know the speed of traffic, live.",
"Simply put. Google knows where you are because you use Google apps and opted in for location tracking. So based on that data, they can predict the busy times by how many people are at that location at a given time."
]
} | [] | [] | [
[
"https://imgur.com/iFiaD3R"
],
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"https://support.google.com/maps/answer/6258979?co=GENIE.Platform%3DAndroid&hl=en"
],
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] |
||
7qlr9j | why can we listen to music at a loud volume, but once it cuts to a commercial or someone talking, it sounds a lot louder? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/7qlr9j/eli5_why_can_we_listen_to_music_at_a_loud_volume/ | {
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"text": [
"Unfortunately certain media volumes are not regulated - television shows themselves might be at a uniform volume, but there's nothing forcing advertisers to make their commercials quieter or the same volume as the show / radio / video / etc.\n\nIt could be used as a tool to hype up someone's memory (evidence suggests that being startled helps you remember something better), or because they want to advertise to the largest audience possible and that might include people who are hard of hearing :\\",
"You know how at the loud volume of your music the music itself has variations in loudness?\n\nSome sounds are louder some are softer.\n\nSo, without changing the volume of your speakers you can encode and change the volume of the music.\n\nAdvertisers know this and just make their sound super loud.\n\nIts illegal in most media in the US. There is a max encoded volume for television commercials, at any rate.",
"What we are experiencing when we percieve the commercials as louder is called compression. \n\n\nWhen watching a movie, the audio is quite dynamic - some sounds are quiet, some are loud, and some are very loud. \n\n\nPeople making commercials don’t need dynamics, they want to be heard. So they apply compression, which means that the difference between the quiet and the loud sounds are diminished, often by a LOT. This gives a fat, dense sound which sounds louder than it actually is, since the audio is less dynamic, but also because the compression also applies to the frequencies of the sound, boosting the low and the high ones generally. \n\nBut, yes - commercials are also louder, since they use compression to get as even a signal as possible, and then turn it up close to max.\n\n\nIf applied poorly, compression can result in what’s known as ”ducking” - for example a commercial with a speaker voice that’s tweaked and compressed on its own, but then you apply too much compression on the main track, so that when the speaker pauses, the background noice or music rushes up to meet the required intensity. This often happens on radio, since they apply their own dynamic range compression, to compensate for differences in volume between albums and songs. Distortion and lack of dynamics are other wanted or unwanted side effects. \n\nGenerally, music is getting more and more compressed, more loud, and less dynamic. \n\nNine Inch Nails were known for producing really loud and compressed albums, but nowadays they don’t really stand out. Arcade Fire and Godspeed you black emperor are other bands that have been quite sucessful in using lots of compression, audio quality wise. ",
"Because it is perceptibly louder, so you pay attention to the commercials.\nThis doesn't mean the volume has gone up, it's that it's been produced in such a way that you take notice when the music stops, for example, vocals in a song must coexist with the music, if your volume is 50 db, then the guitar, keyboards, bass, drums and vocals all sum up 50 db, each one contributes a little bit to the overall volume, but when the announcer comes up and you only hear that voice, then that voice can take up the whole sound spectrum up to 50 db. It can be louder because there is no music to compete with or it is really low.\n\nThe amount of volume hasn't changed but the voice is now louder than the vocals in music which means we now perceive it to be louder.\n\nJust like there are optical illusions, this is an example of an audio illusion. There's a whole field of study devoted to it called psycho acoustics."
]
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||
2j7lhy | why do we grow hair in specific places? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2j7lhy/eli5_why_do_we_grow_hair_in_specific_places/ | {
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"text": [
"Hair in armpits and groin is a dry lubricant, hair on your head is sun protection, men's facial hair is a sexual marker. ",
"I actually had this question in my head, so I'll add on about something else which has been bothering me:\n\nWhy does the hair in our head have such a specific \"shape\"? It stops around your forehead but extends down your sideburns, goes around your ears and forms sharp edges around the back of your head. And it's the same for most people. How is this regulated?"
]
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||
dtclmy | when you suck on an m & m, why does it feel smooth, then rough, then smooth again? | If you haven't tried it before, try it now. Go on, you deserve it. Notice how it feels smooth, then feels rough, and then the rough kinda licks off? Yeah, please ELI5 why this is. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dtclmy/eli5_when_you_suck_on_an_mm_why_does_it_feel/ | {
"a_id": [
"f6vw004"
],
"score": [
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"text": [
"The smooth part is likely the candy glaze, the rough would be the actual shell of the m & m and then the chocolate."
]
} | [] | [] | [
[]
] |
|
80x47m | how and why did apa become the standard for referencing sources? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/80x47m/eli5_how_and_why_did_apa_become_the_standard_for/ | {
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"text": [
"In research papers for publication, it's usually *not* standard (at least in most of the journals I am familiar with), partly due to the simple reason that in printed material *words cost money.* It's more common in review articles, perhaps because in primary research articles the other sources are just used for background while in reviews *most* of the content comes from other places so it makes more sense to show more of the citations. \n\nAlso, APA format has been around longer than computers, and citation-managing software specifically. Nowadays, you can automate citations in a word processor and auto-adjust the numbering pretty easily. But back in the day of typewriters and early word processors, if you wanted to number things you had to *manually* number things. So if you decide to add in another reference later, you would have to manually re-number *everything.* And if you're working with 30, 40, 50+ references... you get the idea. "
]
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[]
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||
23khvf | is a 200hp car two times faster than a 100hp car? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/23khvf/eli5_is_a_200hp_car_two_times_faster_than_a_100hp/ | {
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"No, it just has twice as much health",
"Most likely not. The horsepower is a rating of the power output of the engine, but the power consumption of a car doesn't usually scale linearly with speed. For example, aerodynamic drag is approximately proportional to the ~~fourth~~ third power of speed, and rolling resistance is quadratic.",
"No.\nThe faster you go, the more wind and rolling resistance you generate. This number goes up exponentially, not linearly. \n\nSimplifying it a lot, it looks like the horsepower needed to overcome just air resistance increases by a power of 3, plus a bunch of funny constants we're going to ignore for this example. Ignoring all the constants to simplify to the meat of the equation, you'll get something like Horsepower Needed = Speed ^ 3. The numbers this gives are way off from realistic, though, so we'll just adjust by a factor of 10000 to get normal looking numbers, giving us \n\n Horsepower Needed = (Speed ^ 3) / 10,000\n\n Again, this isn't the real formula, just an order approximation. \n\n\nPunching in a few numbers with this *extremely* simplified version of things, you'll get: \n\n 100hp = max 100mph\n\n 340hp = max 150mph \n\n 800hp = max 200mph\n\n 1500hp = max 250mph \n\n\nIf you're a bit older than five, go ahead and read here: [linky](_URL_0_)"
]
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"http://phors.locost7.info/phors06.htm"
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||
4xkant | why do actors tend to put themselves as "executive producers" & "producers" after being in a television show for a while? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4xkant/eli5_why_do_actors_tend_to_put_themselves_as/ | {
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"text": [
"This indicates they are not only acting in the show, but taking a stronger creative or production role *behind the scenes*. They are working on MAKING the show in addition to appearing on screen, but not every actor makes this change.",
"It may be just a prestige title, but it may also reflect that when they renegotiated their contract they got some % share of the shows profits."
]
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[],
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] |
||
4it3h5 | the tingling sound in total silence | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4it3h5/eli5the_tingling_sound_in_total_silence/ | {
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"text": [
"It's your ears trying to make up for that lack of sound you're not hearing. Same thing goes for the tingling/numb feeling you get when your appendages fall asleep ",
"One form of what you're talking about is tinnitus, ringing in the ears which can be a result of age-related hearing loss, over-exposure to loud sounds (such as at frequent loud concerts or a construction job), or even sometimes brain injuries/tumors. Killing off the hair cells in your ear through loud noises leads to spontaneous activity of the neurons they're connected to, which is interpreted as sound. However, you might be referring more generally to the idea of hearing slight ringing or \"tingly\" noises in total silence even in people without tinnitus, something which often happens particularly after exposure to loud noises for a length of time.\n\nNeurally, this tingly sound doesn't have a definitive explanation, but one perspective is as follows. Essentially, neurons in the ear, like most neurons (i.e., the auditory nerve) are firing regardless of whether you are hearing sounds; they just fire more in response to loud noises. The brain knows this, and so it tends to interpret overall firing rates (and some more complex patterns, etc. of firing) relative to a baseline, no-noise firing rate as 'sound.' However, this isn't a perfect process, so even in the absence of any sounds, there is some activity that might be interpreted as ringing by the brain.\n\nThis explanation isn't complete, and I'm not an expert on auditory neuroscience. Maybe someone who is can add to it!",
"The rushing, almost roaring sound you hear is your blood flow, which is why when you \"flex\" your ears it gets louder.",
"they have drugs for tinnitus now. if u are willing to have ED, hypertension, and bloody stool. my answer was no, but to each his own.",
"Can everybody just chill out with the tinnitus diagnosis? Tinnitus is comparatively rare, and what OP is talking about sounds like what basically everybody who's ever been in a silent space has noticed."
]
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||
3plvye | why is the metric system so perfect in regards to water mass versus weight? | I'm not entirely sure how to word this but basically i'm wanting to know how and what the metric system is designed or based around.
Mainly the fact around 1sq cm equals 1 gram of water and this obviously transfers to 1sqm equals 1 ton etc etc
so i this just pure universe coincidence that weights and sizes mesh so perfectly or was it originally based off water weight? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3plvye/eli5why_is_the_metric_system_so_perfect_in/ | {
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"text": [
"It's originally designed this way. Units in the SI system are all defined by certain basic quantities, like a liter of water or one Kelvin, or one meter and so on.\n\nex: a kilocalorie (a calorie to all dieters) is the amount of energy required to raise the temperature of one liter of water by one kelvin.\n\nSo it's right there in the definition of the unit.",
"Because it's the way the creators designed it. If you were half way around the world and needed something to reference weight to you could just take a known volume of water.",
"I am not completely sure and the history is very complicated but I believe that the metre as a totally arbitrary measure came first. Then the gram was based on the weight of water at freezing point that would fit in 100th of a metre cubed.",
"The meter was original intended to be one ten millionth of the distance from the equator to the north pole along the earth's surface. (In practise it was the distance between 2 scratches on a certain iron bar kept at a lab near Paris, as you can't just measure the distance from the equator to the north pole whenever you want. Eventually they decided that the scratches on the bar was the definition of the meter, not just a local secondary estimate of a meter. And swapped the iron bar for one of a platinum-iridium alloy that was less subject to corrosion and thermal expansion. But it took a long time to decide on these things.)\n\nOnce they had the meter, more or less, they then picked the unit of weight so that it had the relationship you mentioned, that one gram is the weight of one millionth of a cubic meter of water. So that is not a coincidence at all.\n\nBut, it is not very practical to use two scratches on a 3 foot long iron bar to construct a very precise thimble, and then get ultra pure water to exactly fill that thimble at a certain temperature. So while the gram was inspired by the weight of a cc of water, that was not the actual definition of the gram, or at least not for more than a few years, they quickly switched to using another hunk of metal instead, and decided a gram was one thousandth of that.\n\nSo no, not a coincidence.\n\nBut there is one natural coincidence in here though. A competing definition (or inspiration) for the length of a meter was the length of a pendulum whose swing was exactly one second. The pendulum based definition and the earth-distance based definition happen to be very close to each other."
]
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2y5uju | how does keeping an avocado seed with the raw avocado 'meat' keep it from browning? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2y5uju/eli5_how_does_keeping_an_avocado_seed_with_the/ | {
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"[Here's a pretty good write-up of why Avocados turn brown](_URL_0_)\n\nIn short, it's the exposure to oxygen that makes the flesh turn brown. Keeping the stone (seed) with the meat does not prevent this in any way.\n\nFun fact about avocados: the trees release enzymes preventing ripening of the fruit, once they're picked they lose the enzymes. This allows the fruits to stay \"fresh\" on the tree far longer. \n\n",
"It doesn't. Exposing the meat to air will oxidize it and turn it brown no matter what. However, oil can help slow browning and acids will denature the enzymes responsible for oxidation."
]
} | [] | [] | [
[
"http://www.compoundchem.com/2014/08/03/why-do-avocados-turn-brown-the-chemistry-of-avocados/"
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||
dfmq7e | why are tiff files so large? | I have a Panasonic G85 that produces 18MP raw files. But if I edit in PS, even without adding layers, the resultant tiff files are around 150MP. Where is all this extra data coming from? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/dfmq7e/eli5_why_are_tiff_files_so_large/ | {
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"1. TIFF (also known as TIF), file types ending in .tif\nTIFF stands for Tagged Image File Format. TIFF images create very large file sizes. TIFF images are uncompressed and thus contain a lot of detailed image data (which is why the files are so big) TIFFs are also extremely flexible in terms of color (they can be grayscale, or CMYK for print, or RGB for web) and content (layers, image tags).\nTIFF is the most common file type used in photo software (such as Photoshop), as well as page layout software (such as Quark and InDesign), again because a TIFF contains a lot of image data.\n\nSource: _URL_0_",
" > 18MP \n\n > 150MP\n\nI'm guessing that the first is actually meant to read MP, while the second should probably read \"MB\"? Because \"MP\" means \"MegaPixel\" (million pixels), while \"MB\" means \"Mega Bytes\" (million/ 2^(20) bytes).\n\nSo let's take a look at how much that actually is: \n150/18 = 8.333…\n\nSo for every pixel, there are eight and a bit bytes used. Let's just call it an even eight and attribute the rest to metadata (when was the photo taken, what were the iso, shutter etc. settings, maybe GPS coordinates, etc.).\n\nDepending on your colour scheme (RGB/ CMYK/ RGBa/ …) and bit-depth (8-bit/ 16-bit/ 24-bit (\"true colour\") / …), this leaves between one and two bytes per pixel and colour channel. That actually sounds very reasonable. Heck, it isn't even enough to give you true-colour RGB - that would need 3\\*3=9 bytes per pixel (three colour channels, each of which having a precision of 24 bits = 8 bytes).\n\n & #x200B;\n\nThe reason other formats like jpeg or png will generally produce far smaller files is that they utilize (lossy) compression, which simply means that they don't save a colour value for every single pixel but instead try to save space by doing thing like saving \"the next five pixels all have this colour: \\[…\\]\" (very simplified)."
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ebnkco | how do we develop crushes on people? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/ebnkco/eli5_how_do_we_develop_crushes_on_people/ | {
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"you see someone you find attractive and then you get a bone bone and decide that you want to make a hooman with them",
"Lots of different reasons. Most influential factors include:\n- Proximity: You’re more likely to have a crush on someone who you have multiple classes with each day than you are to have a crush on someone who lives across the country.\n\n- Pheromones: Chemical signals, so to speak, that indicate a good genetic match or a person who is ovulating, to name a couple examples (there’s been a study where people use unscented soaps and deodorants and wear the same white t-shirt to bed every night for a week and then different people come to the lab and sniff the shirts to decide which person they find most attractive based on pheromones more or less. Heterosexual men prefer the shirts of women who are ovulating, and also like the smell of shirts worn by homosexual men the least)\n\n- Similar Levels of Attractiveness: This applies a bit more to the kind of person you actually end up in a relationship in as opposed to a crush. But a person tends to pursue people who are about the same level of attractiveness as they themselves are. This way, you protect your ego because you perceive the crush to be less likely to reject you. There are obviously exceptions to this (20 year old women dating wealthy 70 year old men, as an extreme example)\n\n- Admirable Qualities: That person has some sort of qualities that you would like to adopt in yourself or associate with your internal image of your ideal self. A person who is socially awkward and anxious and wishes they weren’t, for example, might have a secret crush on the outgoing, friendly person who strikes up conversations with the people who look like they could use a friend. This has a limitation: our egos come first - we don’t want people who we perceive as being so much better than ourselves that we feel inferior.\n\n- Time: The more time you spend with a person (similar to proximity), the more you start to really pay attention to a person. Think of the experiment where complete strangers stare into each other’s eyes for minutes at a time, and by the end of it, they feel a bit more comfortable with them even if they never exchange words. \n\n\nThere are a looooot more but these are the most commonly observed in lab settings\n\n\nSource: Psychology of Relationships and Intimacy class in college; also have a degree in psychology.\n\nEdit: Pressed enter between each bullet for better readability"
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29qo5i | why charities with similar goals don't merge to become more effective? | I saw today on my Facebook newsfeed of a video for I already forgot the name but a charity that provides clean drinking water to poor villages in Africa.
I am all for the cause because everyone in the world should have clean water at a bare minimum. That said, I know I have seen at least 2 other charities with the same goal.
Why do these charities not merge, combine funds and resources, and provide more marketing campaigns and build more wells?
The only thing that comes to mind is el hefe of each charity wants his final say in how things are done and/or some want to push their agenda (be it a political/religious/etc affiliation). Please tell me it is not that ignorant? There has to be more reasons, right? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/29qo5i/eli5_why_charities_with_similar_goals_dont_merge/ | {
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"That would require a lot of profit sharing for the lawyers and executives. Charities more proficient at throwing celebrity endorsed, wine and cheese events aren't going to share their spoils with the smaller outfits holding three legged races at a park.\n\nAbove all it's about paying the bills and lining their pockets. Whatever is left over goes to build wells, cancer research, etc.",
"Merging companies (and yes, non-profits are companies) requires a lot of work. First, just because two companies do the same thing does not mean that they could merge easily. What if one is a Catholic charity, and the other is non-religious? Is the new charity religious or not? Which of the two Presidents is going to be in charge? Are you going to fire a bunch of staff? If not, how is it more efficient to have 1 big company with twice as many workers?\n\nCompanies merge when it makes some financial sense. Since non-profits are not in it to maximize value, they don't have to worry about being the biggest and best.",
"Corruption is a big one, lots of charities run at the minimum spending to be called a charity and you don't know which ones are/to what degree profiteering unless they show you their books.",
"Because most these non profit charities actually rake in a lot of money that goes to CEOs and higher ups. They aren't about to lose money like that.",
"I was talking to a well to do person who wanted to found a charity that did what the Red Cross did. I asked her why she didn't make a donation, volunteer or apply for a job. She didn't want to \"work for another organization\". She wanted to be the CEO.\n\nIn this case, it was her personal ego and desire to have her name be on the marquee.",
"The simple answer is that they don't become more effective by merging. Mergers of all kinds tend to cause bloat within companies. Non-profits rely on being nimble, quick to act, and flexible to changing needs and conditions. As they become too large, they are less able to do all of those things.\n\nAnd then they have larger infrastructure to maintain, which takes money away from where it is needed.",
"[Sometimes they do.](_URL_0_)\n\nProper answer: Some charities that raise money for the \"same\" thing might be focusing on different aspects of it. If the issue is big enough multiple charities might be able to do this very well without getting in each other's way.",
"Because everyone would lose their jobs.",
"I work full time for a not for profit organization so I can tell you my point of view. I'll try to explain why your question, to me, sounds a lot like 'why don't all grocery stores and restaurants of the world merge together to be more efficient and make more money'...\n\nThe biggest reason is that we often we have different 'specialities'. For example one might be very adept at mobilizing students as volunteers; or be very specialized to deliver programs to a specific audience (specific age group, type of community, etc). Everything in the organization (staff, resources, mentality, values) etc could be geared towards that. Trying to merge might end being like trying to merge a restaurant and grocery store.... it might not really be more efficient. \n\nAlso I'll add that most NFPs I have worked with are really driven by the passion of the people working there, and that has to be considered a resource, too. Where I work, and pretty much any other NFP that I have had the inside scoop on, we make a lot less money than if we worked in equivalent jobs in the for profit sector. So we are motivated by different things than money. Often it's the belief in our cause or a love of the methods through which we work towards our cause. I'm motivated by our program and all its side benefits (the personal growth our volunteers go through) as much as I like the outcome of our work. If my organization merged with another one that used a totally different approach and I lost that aspect of things, I might not stick around for my job, which I think would be a loss for 'the cause'. I guess I'm just trying to give another example of another benefit of having different means to the same end... motivating people / harnessing their passion is important for NFPs because salary is not going to cut it (even more so if your are working with volunteers)! \n\nThrough my work, I often meet people who work/run other not for profit organizations with similar goals. Usually we explain our organizations to each other and then we try to see if we can partner. For example I might be able to provide a pool of trained/keen/screened volunteers to deliver a resource that they have created but don't have the manpower to deliver themselves. Whenever we create a new program, we look carefully at what already exists so that we don't duplicate anything. I think everyone finds their niche and develops their expertise accordingly. Sometimes I do encounter smaller group that have just started a new program that is really similar to what we do, and I feel they are reinventing the wheel (often students... who had a good idea and didn't take the time to research if other similar programs existed). I usually offer to bring them under our umbrella, sometimes it works, but sometimes running their own thing (as volunteers) is their motivation so it's important to them to continue on their own. When you are working with volunteers, the time they donate is a scarce resource (like money) and if they'll donate more by having ownership of their own initiative, then it might be more efficient to let them lead their own thing.\n\nAnyways, I don't think it's a bad thing overall that we don't all merge together. A little healthy 'competition' is a good thing like it would be for any companies. We are all competing for funding from government, corporations, and individuals, and it makes us try harder!\n\nPS. It really frustrates me when people say that NFPs are ways of lining their pockets. I know there have been some bad apples but there are bad apples in everything. Where I work and any other organization that I hae first hand knowledge of, our salaries are very low compared to what we would make in industry, and the CEO's salary is extremely reasonable. We are audited every year and there are a lot of regulations in place by the government (in my country anyways). I'm really sad that some bad apples are giving a bad reputation to the sector and potentially hurting us all.",
"higher-ups won't get most of the money that's used for \"administration\""
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22s0k5 | why are endorphins not used as the ultimate drug? | At the end of thr day drugs are taken so thr user will feel better, why don't we see people injecting this or any other happy hormones? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/22s0k5/eli5_why_are_endorphins_not_used_as_the_ultimate/ | {
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"They are. Heroin and opioid/opiate narcotics are basically just synthetic endorphins. ",
"Endorphins can't cross the blood-brain barrier. Injecting or injesting them won't actually do anything, because they won't get to the receptors on which they exert their \"feel-good\" effect."
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5birw9 | if pre-election polling is mostly done by phone interviews via landline, and the number of landlines is declining among most demographic groups, why are they still fairly accurate? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5birw9/eli5_if_preelection_polling_is_mostly_done_by/ | {
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"It is not accurate that \"... poling is mostly done by phone interviews via landline\". Actual polling companies call cellphones and have non-phone ways of reaching people. \"Polls\" limited to landlines are badly disguised political activism.",
"I forget which election, but I believe it was Wilson. The polls were heavily in his opponents favor, however Wilson won by a decent margin. This was due to the fact that only rich people had phones, and therefore only rich people were included in poles. ",
"[NPR Politics Podcast - Polls](_URL_0_) \n\nCheck out this podcast. They talk to a Pollster from Pew Research Center about this very subject. ",
"If you know the demographics of the population you're polling, and you know the demographics of the actual people you get ahold of on the phone, you can then weight the results to adjust for the polling discrepancy.\n\nExample: Lets say your polling population is 50/50 men/women. You then call a bunch of people to actually poll them, and realize the people who pick up the phone are 25/75 men/women. Since you know the population should be 50/50, you count each male response twice to account for the polling discrepancy.\n\nIn practice it's more complicated, but the principle is the same, and the adjustment methodologies are documented for any legitimate poll. (So they can be peer reviewed)"
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19x933 | how did the golden eye disk hold a full game and an emulator with 10 games only on 12mb? | If an album is like 80 mb how do they have all the textures and a.i and music, plus this emulator I just read about? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/19x933/eli5_how_did_the_golden_eye_disk_hold_a_full_game/ | {
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"It is a game contained in a ROM and the emulator is what allows you to play access the ROM. There is not as much data as you think.",
"I'm pretty sure the music is synthesized. The music actually stored on the cartridge is basically just the musical notes it should play, instead of having the actual sound data. The console then has a built in sequencer that reads the notes and plays them. The music files aren't thus very large at all.\n\nThe textures are very low quality, and probably take up most of the 12 megabytes. \n\nI'm not sure what you mean by emulator, but that is just additional code that probably doesn't take up a lot of space.",
"because older games like that kept lists of instructions on how to play the music, and how to draw the video, instead of storing the already processed and ready video and sound. The instructions lists take a lot less space than the methods we use to store video these days. Modern Mp3 files, and videos are completed music and video that have already been processed, and take up a lot more space."
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2msxdo | how do the big torrent uploaders like yify, eztv, etc, not get caught? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2msxdo/eli5_how_do_the_big_torrent_uploaders_like_yify/ | {
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"There can be many reasons:\n\n- hiding behind a VPN or TOR or another proxy, or all of those; remember that there still are countries where piracy is not regulated by law\n- initial seeding from a remote server\n- actually living in a country with no laws against piracy\n- all of the above\n\nI also doubt that they are *that* heavily hunted for. The authorities have much bigger Internet problems like hacking, fraud, drug trade. ",
"Well actually those are not the actual source of the pirated content. The content usually comes from scene groups like KILLERS, DIMENSION for tv shows, RELOADED, SKIDROW for games etc. I'm not really sure if torrent is the first platform these original files appear in. The ones OP mentions are just known uploaders on public trackers like The Pirate Bay. You won't find those on private trackers. \n\n\n\nOP, you'll have a better chance of getting good answers to your question if you ask it in /r/Trackers"
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5kuu9h | what is the difference between "_url_1_" and "_url_0_"? i know that they are one and the same, but in general i want to understand how the domain name works. | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5kuu9h/eli5_what_is_the_difference_between/ | {
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"_URL_0_ is what is called a subdomain. _URL_1_ is called a subdirectory. Pretty much the same on the server side except that a subdirectory is within a domain's directory while a subdomain is outside a domain's directory, yet has its address response to the initial domain. The reason that those particular two respond to the same place is that both addresses go to the same server location.\n\nresource: I work in websites and hosting. ",
"\nThere are two protocols here:\n\n- The Domain Name System (DNS for short) resolves a text domain name, like \"_URL_3_\", to a numeric IP address, like \"10.234.56.7\".\n\n- The Hyper-Text Transfer Protocol (HTTP for short, or HTTPS if you use the Secure version) allows you to request websites from a computer at an IP address.\n\nIf you type \"_URL_3_\" into your browser, first the browser will add the transform the URL into \"_URL_0_/\". The missing parts added are \"http://\" which specifies the protocol, and \"/\" which specifies a resource. It will ask your ISP's DNS for the address of \"_URL_3_\", be informed by the DNS server that the address is 10.234.56.7, then send an HTTP request to 10.234.56.7 for the \"/\" resource.\n\nIf you type \"_URL_2_\" into your browser, again the browser will transform the URL, this time into \"_URL_1_\". The resource part \"/mail\" was already there, so only the \"http://\" protocol part needed to be added this time. It will ask your ISP's DNS for the address of \"_URL_5_\", be informed by the DNS server that the address is 127.77.88.99, then send an HTTP request to 127.77.88.99 for the \"/mail\" resource.\n\nGoogle has programmed their servers to have both of these URL's do the same thing. For example, \"_URL_1_\" may use an HTTP redirect to tell your browser it should ask for \"_URL_0_\" instead (an HTTP redirect is a reply a website can send to your browser to tell it to request a different URL and change your address bar to match). Another common use for redirects is to redirect the HTTP version of the website to the HTTPS version.\n",
"When you buy an internet name (domain name), you would buy \"_URL_3_\". Once you own that, you can use it for different servers, like _URL_2_, _URL_0_, _URL_1_ or whatever you want. www._URL_3_ would traditionally be used for your companies main web server, but in fact you can set it up anyway you want.\n\nEverything after the slash indicates a different directory or application on that server. So maybe on your server you have a /mail folder, maybe a /games folder or whatever you want.\n\nIf you want to go beyond ELI5, you can use technologies like URL rewriting or BigIP iRules or host name bindings where you can parse domain names however you want and the guidelines I wrote above can be bypassed.\n",
"Breaking up the `_URL_0_/mail` URL a bit:\n\n- `_URL_0_` determines *which server you contact* (specifically, you're looking for the server that corresponds to the `www` subdomain registered under the `google` domain, which is registered under the `com` top-level domain.\n\n- `/mail` determines which document you ask the server for (and if this part isn't specified, you effectively just ask for `/`\n\nOf course, since Google owns both `_URL_0_` and `_URL_2_`, they can make both URLs lead to the same page anyway, but this is the difference. One says \"Give me the `/mail` document from the server located at `_URL_0_`, and the other says \"give me the `/` document from the server at `_URL_2_`\".",
"As a web site creator, here is my understanding:\n\nImagine two servers. One is the main site server and the other is a dedicated mail server both of which are wired together. A browser request for \"_URL_0_\" will route the request to the main server and redirect it to the mail server. Where as the \"_URL_1_\" request goes directly to the mail server without the need for passing through the main server. Both methods will use the same IP numbered address.\n\nThe reason for the two variations is because we humans would not remember to enter the numbered IP address and which of the two methods used is determined by the person who programmed the link used to access it. If it was Google staff member it likely would be the direct method. But if it was programmed by another web site they likely would use the main server redirect because they were unaware that a dedicated server exists."
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l1bnx | what exactly happened to gandalf after the snafu at moria? | This was always one of those plot points I could never really wrap my head around. I understand that he became Gandalf the White, but did he die? Did he have some sort of epiphany? Is he the same person?
The books confused me and then when I saw the movies I was even more confused. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/l1bnx/eli5_what_exactly_happened_to_gandalf_after_the/ | {
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"He slays the beast. He dies. While dead, he does things in the afterlife which he never talks about. He is reborn as the white, for I imagine his bravery, valor, and just doing the right thing.\n\nHe then gets taken away by the eagle, taken somewhere where he gives advice, and such, I believe it was to the cliff of the birds.",
"The fall did not kill him or the Balrog. When they landed, the Balrog fled from Gandalf, but he chased it through the myriad of twisting tunnels below ground. After a few days, he finally found and killed it, but not before suffering mortal wounds himself. His spirit went to \"*a place beyond space and time*\", but he was resurrected and returned to Middle Earth, ostensibly because he was needed to defeat Sauron. The books never tell exactly what happened...",
"He slays the beast. He dies. While dead, he does things in the afterlife which he never talks about. He is reborn as the white, for I imagine his bravery, valor, and just doing the right thing.\n\nHe then gets taken away by the eagle, taken somewhere where he gives advice, and such, I believe it was to the cliff of the birds.",
"The fall did not kill him or the Balrog. When they landed, the Balrog fled from Gandalf, but he chased it through the myriad of twisting tunnels below ground. After a few days, he finally found and killed it, but not before suffering mortal wounds himself. His spirit went to \"*a place beyond space and time*\", but he was resurrected and returned to Middle Earth, ostensibly because he was needed to defeat Sauron. The books never tell exactly what happened..."
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66feuh | cryptocurrency mining. what is the process and why is a gpu required? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/66feuh/eli5_cryptocurrency_mining_what_is_the_process/ | {
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"Currency has value in part because it is rare. If you can get however much of it you want, it becomes worthless. Imagine you can just print off $100 bills from home and they count as real dollars. Why, then, would I sell you, I dunno, a used book for $5? I can just print off $100, so why do I want your $5? Or even $500? Or even $5000? I don't need your dollars, I can have as many as I want whenever I want.\n\nLikewise, cryptocurrency derives value in part because of its rarity. You can't just *have* bitcoins. But like real dollars, bitcoins still have to come from *somewhere*. You may be thinking \"dollars come from the US mint\" but that isn't really true. Physical paper dollars come from the US mint, but the underlying *value* of a dollar comes from the goods and services you can use the dollar to purchase. Those goods and services take time and resources to acquire, and the dollar value it takes to purchase the goods and services is assigned based on how much time and the cost of those resources. Take the simplest example: gold.\n\nYou want gold, it's shiny, it's malleable, it doesn't tarnish, it's an important part of electronics, etc. *I* want food, for obvious reasons. I don't know how to farm and I don't have the tools or land for farming. I *do* have the tools and expertise to find gold. The opposite is true for you: you have farming stuff, but no gold-getting stuff. So I will trade my time getting gold, which to me has less value than food, and trade you my gold for your food. Everyone wins, and it's not complicated until you start adding in a bunch of other people all trading for different resources and you need a way to keep track of who owes what to whom, and that's where currency is useful. Assuming nobody is just stamping out money, the amount of currency you have in the system depends on how much of the resources are available and how much time it takes people to get it. If there's a lot of gold to go around, you need more dollars to represent that gold. And getting gold takes *time* and *tools*.\n\nBack to bitcoin: you have to have a way for your cryptocurrency to enter the system. But you can't just dump it in, because then you'll have more currency in your system than you have absolute value in the system, and the currency will be worth less. You also can't just hand it out to people, because that isn't fair, and those people can horde the cryptocurrency and create artificial scarcity, and control the currency such that it's a hassle to use and nobody wants it, which also makes it worth less (although in both cases, perhaps not worthless). You have to have a way for the currency to enter the system *slowly* to keep up with the demand for it, and control who gets it, and give the currency inherent value by making it - like gold - hard to obtain.\n\nThe solution is \"mining\" it. The cryptocurrency is obtained by having your computer \"mine\" it by solving very long, difficult math problems. This takes a lot of time - the problems aren't simple 1+2, they're incredibly complex functions that take even fast computers a very long time to complete. It also takes resources: you can solve more problems with a faster computer, but that means you have to invest in a faster computer. It solves the cryptocurrency dilemma perfect, though, for those reasons: you are investing time and resources, which are inherently valuable, into the cryptocurrency, which makes *it* valuable. And anyone can do it.\n\nGPUs or graphics processing units are useful because they attack computing by using a *lot* of small, efficient processors rather than the traditional CPU (central processing unit) way of doing it, which is to have a few very powerful processors. CPUs solve problems by having a few core processors, like *maybe* eight, doing thousands of processes each second. A GPU has thousands of processors instead, and they each do a few processes each.\n\nGPUs are useful for crypto mining because you can work on many different functions simultaneously, and the functions can be broken down into smaller, easier problems that can be solved in parallel. Compare that to a normal CPU that would solve one of the functions much faster, but has to solve *just that one* function, in its entirety, before moving onto the next one. It's the difference between having a tiny group of miners that work really fast and nonstop, but are all in the same mine, and having thousands of miners that are kind of ok at mining but you have hundreds of them in each mine and you have hundreds of different mines."
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8u2m40 | if a 213g potato has .2g of fat, 4.3g of protein, and 37g of carbs, what is the other 171.5g? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/8u2m40/eli5_if_a_213g_potato_has_2g_of_fat_43g_of/ | {
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"Net carbs? If yes, most of the rest is fiber",
"Water, fibre, and other things that humans don't digest into energy."
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4z2wxw | if you sweat salt does that mean your body needs more salt or it already had too much? | If that's a sign the body needs more then why is it that drinking salt water can kill you, but adding salt to water won't? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4z2wxw/eli5if_you_sweat_salt_does_that_mean_your_body/ | {
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"One of those pesky \"electrolytes\" all these sports drink companies are trying to sell us on buying, salt (or sodium, if you prefer) is necessary for proper bodily function.\n\nSea water has a an average content of about 35 parts per thousand, so for every liter (1000ml) of seawater, you've got 35 grams of salt.\nThe reason it's harmful to drink seawater is because the human kidney is only capable of making urine that is LESS salty than 35 parts per thousand, so you'd have to urinate more liquid than the content of the seawater. Your body literally dehydrates faster than you can drink it.\n\nYou can drink small amounts of seawater occasionally, so don't worry if you get a little in your mouth when you're swimming at the beach. Just don't make it a habit.\n\nWhen you add a little salt to some water, you're adding much much less than that, so it's not a problem. Neither is having some salt in your food, because we take in so much more water per day than is required to filter out the salt. Even your food as water in it!\n\nEDIT: I forgot to answer the main question!\nYes, your body needs salt. And yes, when you sweat, a small part of that is salt. \nYou get all you need from the foods you eat, even if you don't eat processed foods that are high in sodium, so don't worry about it.\nIt doesn't mean your body had \"excess salt\", nor should you worry about trying to put extra salt on your food later to compensate. ",
"I don't know if this will help you out, but once I was training for a half marathon. I didn't hydrate well during a 20k run once and had sweat a lot during the run. At the end of it, I could brush off the salt crystals which had formed on my skin. About 30 minutes after that my leg muscles started cramping like crazy. The pain was more intense than just delayed onset muscle soreness or lactic acid build up. I limped back to the building I was training in and just knew I needed salt water. It was part instinct and part basic medical knowledge I had that told me I needed specifically salt water. I managed to get my mitts on a package of salt and mixed that into some water. 15-20 min later, the cramps eased off. The water tasted horrible, but was absolutely necessary.\n\nI'm sure pro athletes have a perfect routine that works for them with regards to electrolyte balance during their events, and I learned my lesson with regards to my requirements during long runs in a hot environment."
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141c9n | what is the impact of palestine being promoted to "non-member observer status" in the un? | Will this lead to any change in the Israeli-Palestine conflict?
What does the future look like now for Palestinians? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/141c9n/eli5_what_is_the_impact_of_palestine_being/ | {
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"It's not a full UN membership but it's a more symbolic move since it gives them more status than before. They are now on the same level as the Vatican and Switzerland (until a few years ago). \n\nIf they now try to join the international criminal court, this status of theirs will give them more 'points' in their favor. That's quite important.\n\nAlso, they can now go to many UN meetings. So mostly it's a step forward."
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j3e4d | why can't a state just print more banknotes to create more money? [li5] | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/j3e4d/why_cant_a_state_just_print_more_banknotes_to/ | {
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"Think of a rare baseball card. If there's only 10 of them in existence, then everyone would want them and they would be willing to trade hundreds of chocolate bars for it. \nNow think if they printed 990 more of that rare baseball card. Now everyone has one, and no one is willing to trade a chocolate bar for it.",
"Money stands for things. A dollar stands for a dollar's worth of bread, or gold, or land. We invented money so we don't have to swap chickens and stuff to buy things. It's a lot easier. \n\nNow. Paper money used to be backed up by gold. The U.S. had, say, a billion dollars of gold, and so it put out a billion dollars of paper money. The paper dollar was a promise that you could go get a dollar in gold. Today, there isn't enough gold to back up all the paper money in the world. So paper money is a promise that the government can pay you back. Using dollars says that you believe in the government. That you believe the people of the United States will be rich enough and hardworking enough - and lucky enough! - to always pay back their loans.\n\nNow, if you keep printing dollars, then it's like making too many promises. If you promise that you'll wash the dishes, you can't promise to mow the lawn at the same time. People start to think you're lying. And then they don't believe in your promises as much. The same thing happens to money. If you print a whole bunch of dollars, without making the government run better or showing that people are working harder and making more money, then that's the same as breaking a promise. People won't use dollars - or they'll say it's not worth as much. \n\nSo printing too many dollars won't make more money. It will make money worth less. ",
"By printing more money, you devalue it."
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3mvqaq | what is the "sharing economy"? | A good example would be ride share programs like Uber (vs. traditional taxi services). How is Uber not just another taxi service? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3mvqaq/eli5_what_is_the_sharing_economy/ | {
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"Instead of being full time taxi drivers anyone with a car and a license can hop on and be an uber driver.\n\nSimilarly, Airbnb allows individuals to host people in their homes as a hotel would.\n\nThe \"sharing\" idea is that personal assets (cars, homes, etc.) are utilized to provide services for a fee instead of assets that are wholly dedicated to providing those services.",
"Benjamen Walker's podcast 'Theory of Everything' did a great three-part series on this, called 'Instaserfs'. Opinions differ, but their angle is that it's startups convincing freelance casual workers that minimum-wage gigs are in some way empowering.\n\nPodcast here: _URL_0_"
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3557k4 | is hemp realistically a great replacement for many materials (plastics and papers) or has this been over emphasized by those seeking legal marijuana? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3557k4/eli5_is_hemp_realistically_a_great_replacement/ | {
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"Hemp is a decent replacement for a broad range of things. You won't see paper companies switching from wood to hemp just because it's legalized. \n\nAlso hemp contains almost none of the active ingredients that recreational marijuana has (you can't get high off of it)."
]
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3k2yr9 | what's a military formation? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3k2yr9/eli5_whats_a_military_formation/ | {
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"Any set of soldiers marching under one command, usually in a regular form.\n\nAlready Egyptians did so that the they had the less experienced at the front, and the more experienced at the back, to prevent retreat and fill in gaps. The ancient Greeks invented the phalanx. The enemy can do more damage if they can strike multiple soldiers or go behind them and hit them for the side or back. If the soldiers form an unbroken line, no one can get through and the enemy can face the formation only from the front, which is strongest. The shields are locked together, so there is one long armored wall. But, some of the soldiers are struck and killed, so there will be holes in the line. If there is already another line behind it, the gap is easily filled.\n\nThe formation is psychologically effective against unorganized fighters, but degenerates into a pushing match in phalanx-to-phalanx combat.\n\nClosed formations were used also even in the firearms era. But, he machine gun made them useless as an actual fighting formation. Still, soldiers are taught to walk and move about in formation in military drill. It creates a sense of an organized force and develops discipline.",
"It can also apply to vehicles, such as tanks, planes, or ships.\n\nSimplified:\n\nThink of the \"line of battle\" used by British and French fleets during the Napoleonic wars; all the ships spaced out nose to tail, guns pointing sideways (a ship's sides could fit more guns than the front). If ships broke formation and became positioned side by side, one of them would get in the way of the other's guns.\n\nOr world war 2, when allied bombers over Europe would fly in squad formations, and several squads formed into bigger formations. This would allow the defensive machine gunners in each bomber to \"cover\" each other from Nazi fighter planes, and also reduce the time over hostile flak cannons. If you fly one at a time over hostile AA, it's gonna be easy to pick you off. If you all fly to the target independently, the lack o f coordination is going to cause a collision. Ergo, fly in a formation.\n\nBack to infantry: you grunts at Waterloo might be facing direct cannon fire, or cavalry charges. Best thing to do in case of cannon is to form a side-by-side skirmish line so that if cannon balls come at you they hit one guy at most. \n\nBut then what if you get charged by bojack horsemen? Each one of you standing unreinforced is going to probably get cut down by a fast-moving cavalry saber. Best thing to do in that case is form a square. That way, no matter what direction the very mobile cavalry charges from, it's repulsed by disciplined musketry. \n\nThe faster your unit can change formations, the likelier y'all are to survive on the battlefield."
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c84ty8 | what do people who speak different languages hear when someone speaks english? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/c84ty8/eli5_what_do_people_who_speak_different_languages/ | {
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"It sounds just like what you hear when you hear someone speak in a language you don’t know. You can tell they are saying something that means something because their voice is controlled and their body language will tell you they are not just making up sounds like a crazy person. When I hear American English vs United Kingdom English, American English sounds like the mouth is more open so the words are more full sounding. There is a great video online that demonstrates what English sounds. The video uses a mix of English words and gibberish, but sounds like how an American English speaker would. This is what English would sounds to someone who doesn’t know English. The video can be found [here](_URL_0_) ."
]
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2eu1oj | why do people donate to different cancers (breast, prostate, etc), won't one cure lead to cures for all the others? | [I thought of this question after seeing this chart.](_URL_0_)
Isn't cancer just cancer? And if there isn't just one cure, then which one is most important to uncover the cure for all the others, let's put our focus there first? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2eu1oj/eli5_why_do_people_donate_to_different_cancers/ | {
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"Cancer is actually a term that broadly describes a group of diseases, not just one, where there is uncontrollable cell growth that invades other parts of the body. What this means is that there are a number of different causes as to *why* the cells become cancerous, requiring different types of research to find different causes (i.e. caused by DNA damage in gene A, as opposed to being damaged in gene B, etc). \n\nFor your second question, there is not a most 'important' one to uncover to cure the others. It's like comparing apples to sheep, cancers are different and can even vary between people. While it's possible that the cures may be connected and have the potential to shed light on other types of cancer, this is absolutely not a 100% guarantee. ",
"[This comic sort of sums it up](_URL_0_).",
"Firstly, you have to understand that Susan G Komen is a scam-they aren't raising money for a cure, they're raising money for \"awareness,\" which is a fancy way of saying you're paying them to tell people that breast cancer sucks. Oh yeah, and they're aggressive with lawsuits and very corrupt, that too. ",
"My understanding is that cancer, being that it is an uncontrollable and often random outburst of cell growth, is like a mutation. The cells mutate, get confused, and start screwing things up in other areas of your body. Because of this cancer is not a one-size-fits-all sort of ailment, and therefor has no one-shot quick cure. As /u/TheSeventhCircle said, within the different types of cancer its specific characteristics can change on a person to person basis. That's why finding a \"cure for cancer\" is actually not accurate at all because it isn't a disease or virus, it's your own body attacking itself. Granted it may be possible to find specific causes of it outside of things like exposure to harmful elements (IE a smoker getting lung cancer, an outdoors man getting skin cancer, etc.) which would lead into a more comprehensive understanding of what it is, and therefor a potential cure for its varying forms. However since it is so varied and diverse, I doubt say focusing on curing breast cancer would lead to a breakthrough in the curing of prostate cancer. They're just too different.\n\n\nIn regards to that chart, it is very curious that cancer receives the highest amount of awareness and charity funding where heart disease is forgotten. Perhaps instead of the heartwarming (lol) cancer story in the movies they should show heart disease instead, as that may actually be curable (even though, like cancer, it is an umbrella term). ",
"To put it simply, different cancers are caused by different things. You wouldn't ask is disease just disease? Why won't one cure for disease cure all other disease?",
"Asking why there's no cure for cancer is like asking why there's no cure for having allergies. There's more than one thing that people can be/are allergic to, just like there's more than one thing that might cause cancer."
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28f7b4 | why do they need so much money for cancer research? | What exactly does the money for Cancer go towards? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28f7b4/eli5why_do_they_need_so_much_money_for_cancer/ | {
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"Scientific research costs money - hiring scientists, buying highly specialized equipment, buying the supplies, chemicals, etc... It can cost thousands of dollars to buy a milligram of a single antibody you need for your experiments.\n\nSuccess is also not guaranteed in research, so you can spend millions of dollars over several years and fail in what you're trying to do. Much of research is exploratory, and so lots of scientists are researching a bunch of different things all at the same time.\n\nAssuming your research is \"successful\", turning a research discovery into a marketable product (it needs to make more money than it costs to produce, it needs to be produced on a way larger scale than what was developed in the research lab) is an incredibly hard and costly endeavor. ",
"For some charities, the money is directed almost entirely to research. For example, the Multiple Myeloma Research Foundation has received an A+ rating from _URL_0_ judging by [these criteria](http://www._URL_0_/criteria.html). \n\nOther charities aren't so dedicated to actual research, and instead often are categorized as 'awareness' charities. Now, that's not to say that they weren't started in an attempt to do some good, or that they aren't doing good now, but they're not really helping. Everyone is aware of breast cancer now, but the goal of many of these is to make sure that people get mammograms and do self checks. Why these things aren't part of regular health care exams is an entire other kettle of fish. Groups like the American Breast Cancer Foundation are these sort of groups. Unfortunately only about 25% of their raised funds go to actually help people get exams. The rest is spent on continued fund raising, and that includes pay for their employees and the board.",
"Because the human body is stupidly complex and research on how to keep it from killing itself is really finnicky.\n\nAlso, \"Cancer\" isn't just one disease. There are like, a bajillion different types of cancer with a scrillion different genetic and chemical causes and preventors.",
"Not to cancer research but to the next years marketing campaign.\n\nTo the artists who are hosting the events and who are getting credit for 'their help beating cancer'.\n\nTo the TV commercials and marketing companies. (taking away the biggest chunk)\n\nTo events for cancer survivers. (money must get spent)\n\nTo pay for poor patients chemo and treatment. (okay for me)\n\nTo psychologic assistance for patients and familie. (still a bit okay)\n\nTo everything but cancer research. (not okay)\n\nEdit: but this is an unpopular reality so will get downvoted"
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5x3m2p | what is a car engine really doing when it is "warming up"? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/5x3m2p/eli5_what_is_a_car_engine_really_doing_when_it_is/ | {
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" Well, first off you don't need to warm up the engine of a modern car. They are designed and built to such a fine tolerance you can simply turn them on and drive under normal operating conditions year round.\n\n As to what they are doing they are literally warming up, or getting hotter. Since the engine is made of metal which expands slightly when heated the parts of the engine will expand a bit, and the main engine components (the block and head, or lower and upper part of the engine) will expand enough to float off each other a bit when they get fully heated. \n\n This isn't a worry because the parts have a gasket between them designed to make a proper seal so no oil or radiator fluid leak out. This has been a problem in the past, some engines from the 70's and 80's that leaked notoriously did because newer materials expanded at unpredictable rates. We are well past the days of those exotic (for the time) alloys and early aluminum head/cast iron block hybrids. ",
"they are \"warming\"!\n\nChemical reactions inside the motors are more efficient when happen in a range of temperatures. this is usually especially true in diesel motors.\nMoreover there are other fluids (oil for example) which are less viscous when warmer than ambient temperature, and when it happens motors work better.",
"You are letting the temperature of the engine increase.\n\nIn very cold temperatures, this allows the lubricant to heat to a point it flows more freely before the engine is operated at higher RPMs. \n\nBut mostly it is so the engine will be warm enough to transfer heat to the heater, and warm up the rest of the car."
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3d3ywm | how can i avoid mosquito bites? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/3d3ywm/eli5_how_can_i_avoid_mosquito_bites/ | {
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"Source: I live in the south, and I have visited north east Arkansas which has more mosquitos than air at times. In Texas we have mosquitos that are so large they look like baby wasps. You can clearly see they have black and grey stripes on them. When you smack them on your arm it's a bloody mess. I have a friend that contracted West Nile while at work and I hate itching so I like to avoid them. In order of most to least effective or important:\n\n* Stay indoors around sunset. You will learn that there is a peak time where it's time to seek shelter, just as it starts to cool off. No amount of Deet is going to ward them all off during that time.\n\n* Keep some Deep Woods Off nearby at all times. You don't necessarily have to wear it all the time, but when you get your first bite go ahead and hose down with it. Don't spray it in your face, but be sure and get your back, and the backs of your legs and arms. They love behind the knees. Be careful of overly powerful deet products. I once was handed a DEET wipe that claimed \"maximum strength\". Putting it on my skin made me sick almost instantly and I was not in a place where I could wash it off or remove it effectively.\n\n* Never allow anything to collect water around your living space. Outdoor standing water = mosquito breeding ground. They look like tadpoles in the water but in reality they are satan's spawn. turn over all buckets, or other things collecting water.\n\n* Citronella products can be effective to a point but you have to be close to them. ThermaCELL appliances seem to kinda work but they are expensive and cumbersome. When I go camping I have four cheap hurricane lamps ($5.00 each at Walmart) that I power with citronella lamp oil (~$10.00 for 64oz Walmart). The lamps burn very efficiently if you keep the wik short and they do an ok job of creating a bug free zone. I also just like the look of old timey lamps.\n\n* Wind is your friend. I don't have two ceiling fans on my back porch just for cooling. They are mostly to keep the bugs away. If they can't fly, they can't get you. If you can get in front of a good fan you are not going to be getting bit by mosquitos (as much). \n\nHurricane Lamp:\n_URL_0_\n\nCitronella Lamp Oil:\n_URL_1_"
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4isofh | what are the "loudness wars", why are they happening, and why should anyone care that music is getting louder? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4isofh/eli5_what_are_the_loudness_wars_why_are_they/ | {
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"Music is getting compressed so it sounds louder. Before this you're set your volume to your preferred level and would hear everything from quiet notes to very loud and distinct drum hits. Now the quiet notes are louder, the mid range is louder, and consequently the formerly loud and distinct drum hits are just barely louder than everything else.\n\n[This](_URL_0_) video demonstrates it better than any written description really can.",
"There isn't as much of an issue with it today, so we might be able to say the the war is over, or at the very least, a truce.\n\nLouder tends to sound better. Why? Not really sure, but it is probably just something to do with biology.\n\nThis fact is very important in mixing music because a big issue that is run into constantly is that you will tend to find things to be better the louder they get. It is very easy to trick yourself into thinking that you skillfully EQ'd a track, but in reality, all you did was increase the volume.\n\nNow, the big factor in the loudness wars is compression. The sort of compression we are talking about in essence will make softer sounds louder. If you compress a signal enough, you can make a whisper the same loudness as a yell. This is what is called as reducing the dynamic range, as in the range of loudness is reduced. It may have been previously from -50 to 0 db, but after some heavy compression it is now -20 to 0 db.\n\nYou can see this in the photo below. Where there used to be peaks and valleys, it is just a straight line.\n\n_URL_0_\n\nSo, we can certainly come up with many negatives as to why this is bad. An obvious one is the philosophical question of \"compared to what?\", in that if everything in a song is the same volume, isn't the song neither loud nor soft?\n\nThat is honestly my biggest issue with poorly compressed music. There is never a point where it just hits you. What should be an epic buildup or a sudden spike reduces itself to be less of a surprise. The soft parts are never soft, the loud parts are never loud.\n\nBut, more importantly, there is a very big reason as to why music needs more of this sort compression now compared to before, and that reason is that we listen to music everywhere. \n\nPortable devices are relatively new, and the idea of listening to music on bike rides, on the train, when shopping, when working out, when doing work, riding the lawn mower, and so on was soon to follow. \n\nBut a big problem arose, and that was that while you were at the gym listening to your favorite song and a soft part came on, you couldn't quite hear it because of that noisy elderly couple chatting in the corner, so you turned it up to hear it... and then the loud part came on and you are frantically looking for the volume knob before you blow your eardrums.\n\nThis is a big problem because not only is it annoying to have to constantly adjust the volume, but it can actually do harm to your ears. A decent deal of compression can help this a lot by reducing the dynamic range just enough so that the soft parts are loud enough to hear over that noisy elderly couple, but soft enough to be distinguishable from the loud part. The goal is essentially to have it all audible, retain dynamics, and not have the listener have to touch the volume knob.\n\nYou might be wondering why portable music changed this. Well, it is because you used to have to listen to music in spaces where there wasn't much noise to overcome. You might pop in a record at the silence of your home. With advances in technology, we know listen to music in less suitable places to hear all the details.\n\nWith that said, there is an interesting selection process in how certain genres of music tend to be selected for their venue. Rock music tends to work for hockey stadiums because it is loud, simply, and punchy; whereas classical in the same stadium would softly garble on a sock.",
"People who make the music think that YOU think everything sounds better louder. And they keep trying to outdo each other to sell records. Because of this, they are sacrificing dynamics (highs and lows) for something that's consistently \"loud\". To me, it's also boring and rather tiring especially when it's done obnoxiously. \n\nI have heard it said that the loudness wars are almost over. Since most music is streaming through YouTube and Spotify and they control the loudness... the actual loudness of the recording doesn't matter as much anymore except if you're listening to a cd. And people think their music should probably be loud if they want to get it on the radio, but that's not true because the radio compresses and limits and EQs the music beforehand anyway. \n\nSource : the mastering show (podcast). ",
"It has ruined every single band ever... From Metallica, to my favorite, Parkway Drive. \n\nI saw Parkway Drive perform their new album live and damn near shit myself. There is NO reason a band should sound THAT much better live. \n\nTheir new album has a dynamic range of 5. Fucking embarrassing. ",
"Go listen to an old recording of money for nothing. The dynamics are great. Listen to it loud. If your sound system is bad, it's going to sound bad. If it's good it's going to sound good.\n\nWith the terrible and compressed mixes of today, and compressed in the sense that the dynamics are compressed, a bad sound system will sound a little better and a good one a lot worse than it could. Your ears will get tired faster and stuff like snare drums will sound weak and disappear into the mix.",
"Loudness Wars: The war part. People discover that the audience remembers \"louder\" as \"better\". Some things get louder (like the average volume of Television Commercials).\n\nSo the producers started mixing their tracks \"hotter\" so they'd stand out in play. Most stations mixing on CDs at the time wouldn't spend much time tweaking levels for every song played.\n\nAlso then at parties those tracks would \"pop\".\n\nNow why \"louder is worse\". In both encoding and electronics performance you get lower quality output. The long explanation is skipped here but basically if you run components near their limits they kind of just don't do as well.\n\nSo anyway, If you take, say a classic Police CD and anything modern and play the CDs back-to-back the total difference is amazing.\n\nSo the same song recorded at the \"natural volumes\" will be in the meaty part of the performance and output curves for the decoders and such. (hence the other stuff about compressing signals and such.)\n\nAlso, if people stopped being dicks about the volume, then it would be easier to play music."
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28sb8s | why can hospitals charge $50 a pill for tylenol, but i can buy a whole bottle at the store for $5? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/28sb8s/eli5_why_can_hospitals_charge_50_a_pill_for/ | {
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"My local hospital charged $25000 (to insurance) for the birth of my daughter, a three day affair. That's a lot, but my daughter was severely breached, and my wife needed an emergency c section. They'd both likely be dead if we didn't go to a hospital.\n\nSo if the choice is ludicrous prices or death, what choice do you have?",
"I'm sure the large amount of people that use the ER as a doctors office and don't pay have something to do with it.",
"You're not just paying for the tylenol. You're paying for the nurse to give it to you, to make sure it's the right thing, for the diagnosis from the doctor to give you the tylenol, for anything any of the techs have to do for you, for the bed you're sitting in, for the air conditioning, for the TV, for the electricity, for the hospital administration and record keeping. You're paying for all of it. Going to the hospital for a tylenol is a very silly thing to do.\n\nIt's the exact same reason you get charged $1.99 for a coke at a restaurant, when you can get a whole two liter for $0.99 at the store. You're not just paying for the soda, you're paying to have it brought to you, with ice and a straw, in a social setting, with food available, by a server. Same idea.",
"Because doctors are struggling and don't make enough.",
"Because they can.",
"Because of greed.",
"because insurers haggle over bills. starting way over your target price and negotiating down to where you wanted to be initially is haggling 101.",
"In Denmark... it would cost you about 0$, if it was given to you in the hospital, and you did not have to go buy it at a pharmacy... although, the treatment, the bed, the electricity, the nurse, the doctor.. would add up to the huge sum of 0$... And really... I don´t have a problem with paying for others, because I know that if I (god forbid it) need treatment someday, other will pay for me. I just hope America starts to realise this. Both on healthcare and school system",
"The rationale is that in a hospital, at least two highly trained \nprofessionals have to review whether you should be given that \npill, and a third needs to double check that it's the proper pill,\ngiven at the proper time.\nGiven the rate of 'medication error' problems this isn't as\nridiculous as it appears on the surface.\n\nFor Tylenol, this is ridiculous most of the time, (but \nappropriate in some instances).\n\nStill I agree, = it's bill padding.",
"Insurance companies, Medicaid, Medicare, and people who visit the ER without insurance don't pay $50 a pill. Insurance pays a reasonable amount, Medicaid and Medicare pay about 70% of the pill's cost, and uninsured ER patients pay nothing. Hospitals have to make up the difference somewhere or they'd go out of business.",
"They have to make up the cost from people that don't pay.",
"I am a nurse and I have worked both in a hospital setting as well as a doctor's office setting. This is my understanding of why tings cost so darn much when billed thru a hospital or clinic.\n\nWhen you pay what seems like an exorbitant amount for something like a Tylenol what you are really paying for are things that can't be added to your bill, but you use while in the hospital. Things like electricity, water, staff time, cost of maintaining and upgrading the building/infrastructure, and to help offset things that we can't bill the actual cost because it is too ginormously high.\n\nYou are also paying to of set the cost of what insurance companies write off. For example when I bill a specific code it costs $20 dollars. Insurance A's contract with my hospital reimburses us $10 and requires that we write off the remaining $10. Insurance B's contract pays $15 and we write off $5. Insurance C's contract pays $5 dollars and we write off $15 dollars, and so on and so forth. \n\nSince we can't very well call the electric company and say sorry we didn't get as much reimbursement as we expected this month, what happens is every so often (usually once a year) someone/some committee from the finance department looks are what we need to charge to A)remain competitive with other area hospitals, and B) still be able to pay our bills.",
"Hospital finances are complicated. Bills can vary wildly depending on who is paying the bill. For example medicare sets the \"reasonable and customary\" fee and then generally insurance companies try to negotiate something like that for their members. The only people who would ever see a $50 for tylenol would be the uninsured mostly because the charge is built once and just not adjusted.\n\nWhy would you get an insane number like that? Well insurance companies may reduce the bill by 80% so if the hospital wants $10 for that tylenol they charge $50. Generally though a bill is tied to a Diagnosis Related Group DRG, which more or less says if you have x problem the hospital gets $5000 because it should take 2.1 days. This is just like the mechanic who says a transmission costs $1500 and takes 6 hours. If it takes 3 then yay if it takes 7 then boo. \n\nA big part of hospitals are hidden expenses. Compliance with the myriad of regulations isn't free. Electronic medical records cost plenty and most hospitals gain nothing from them. Safety officer isn't cheap, infectious disease nurses, dietary counseling, diabetes counseling, housekeeping, executive salaries and IT is a big cost. Certain procedures are big dollar losers (mid 5 figures) but physicians have patients who need them so the hospital takes a fat loss to make them happy so they'll do more profitable procedures there. \n\nSo hidden but very real expenses and a complicated billing system make a pretty opaque process. An opaque process can drop crazy bills. ",
"Even different pharmacies have different pricing on prescriptions within the same city. From what I learned, Costco ALWAYS has the lowest pricing compared to Walgreens/other drug stores. I almost had to pay 500 dollars a month for 30 pills, luckily at the end I managed to get insurance and the cost went down to 5 dollars.",
"The average cost of a stay in the ICU for somebody who need ventilated is about $31,000 - $42,000 (over a typical 14 day stay). Poor/homeless/uninsured people receive these treatments, some of whom make multiple emergency room visits per year, and have no way of making their payments. Hospitals inflate prices for insured people and people who can pay for healthcare in order to turn a profit. If you use a hospital, you're payment plan is paying for your care AND the care of the people who had no way of making payment.\n\nEDIT: [source](_URL_0_)",
"They're free in Canada"
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1jp59x | why would someone want to jam gps receivers? | I can obviously see the benefit of being able to jam military GPS, but why would someone want to drive around jamming GPS, other than to be a jerk? TIA! | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jp59x/eli5_why_would_someone_want_to_jam_gps_receivers/ | {
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"The usual reason is people who are commercial drivers who want to do something they aren't allowed to do (take a detour to visit a relative, for example) but their commercial vehicle logs or transmits the vehicle's information to their boss. The vehicle usually gets its location, time, and current speed from GPS, and either logs this information periodically to a recording device or transmits it to the boss/company via the cellular network.\n\nJamming the GPS intermittently as well as when \"needed\" for clandestine activity, and it looks like mechanical GPS / equipment failure.",
"In addition to location data, GPS also provides precise timing data for some applications. If this timing is disrupted, it can usually make whatever it's supporting useless. This can include things from automated toll collection systems to stock exchange trading algorithms. Generally, the people disrupting them do so because they have something to gain by the system's failure."
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4adjfs | is there a fixed amount of money/assets in the world? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/4adjfs/eli5is_there_a_fixed_amount_of_moneyassets_in_the/ | {
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"no it wouldn't. because you can create money out of nothing. aka interest. the amount of money is always going up basically due to interest. ",
"Money roughly approximates the total amount of wealth in the world.\n\nEvery time someone pulls a rock out of the ground, encourages a plant to grow, or composes a hit single, wealth is created, and eventually, money will be created to reflect this.",
"Money is an arbitrary abstraction of wealth. There is no limit to how much money is in the world."
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3tfjyc | how do processors work? how is a simple silicon chip able to perform calculations? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/3tfjyc/eli5_how_do_processors_work_how_is_a_simple/ | {
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"This is a complicated topic built on very simple ideas. If you go step by step you should be able to wrap your head around it.\n\n**What is a semi-conductor?** Starting all the way down at the atomic level. In pure silicon crystals, the atoms are neatly arranged, and all have their outer electron shell full, so it won't conduct electricity because all the electrons are nice and cosy. By adding impurities into the crystal, we make two types of semiconductors,: P and N. N (negative) has more electrons, so it's willing to give them away and P has fewer electrons (positive) so it's glad to take in electrons.\n\nYou [put a chunk of N next to P](_URL_4_) and you have a diode. Pass electric current (aka a flow of electrons, but in the other direction) through it in the P-N direction, and the electrons will flow freely. however if you pass current in the N-P direction, the part where the two semiconducting materials meet will become \"full\" of electrons, like natural silicon crystals, building a wall between the N and P where electrons don't want to move, and any new electrons will hit that wall and won't be able to move forward, instead they'll just keep building that cosy wall.\n\nSo we can force electricity to only pass one way through a circuit, pretty cool...now what?\n\n**What is a transistor?** By [sandwiching semiconductors](_URL_3_) in an N-P-N or P-N-P way, and attaching electrodes (wires), we have a component that will behave differently depending where the electron flow comes from. This was first used as an amplifier (like a transistor radio), But can also be [used as a switch](_URL_1_).\n\nDepending which part you put current in, what comes out of the transistor will either be current or no current.\n\n**Logic circuits.**\nNow that we have this little thing that can switch depending on if it has current or not, we can string a bunch of them together in various ways to make boolean logic circuits. boolean just means you either have yes or no, or, in binary, 1 or 0.\n\nHere's a [NAND gate](_URL_0_), meaning *not and*, as you can see it pretty much looks like a transistor, because it is! You have two inputs, and if A has current (A=1) and B has current (B=1), it will put out a 0 (because it's a *not and*).\n\n[Here's a basic XOR, *exclusive or* gate](_URL_2_), meaning that A need to be 1 or B needs to be 1 for Q to be 1, but if A and B are both 0 or both 1, Q will be 0. This is just one way basic AND or NAND gates can be strung together.\n\nNow slap a few billion of these together in a CPU and you have a logic machine that can do all kinds of calculations.\n(sorry for the brief ending, I ran out of time, hope you learned something)\n\nEDIT: thanks to all the other people explaining boolean arithmetic on a higher level. Teamwork, yay!\n\nEDIT2: Fixed some links and hopefully cleared up the confusion between electron flow and current.",
"You have transistors the size of about 70x70x70 atoms. So even in a tiny chip you can have a fucktonbazillion of the basic elements.",
"There is nothing simple about it. Processors are quite possibly the most complicated thing mankind has ever invented. Learning how one works is a semester long 300 level EE class that's not a lot of fun. \n\nTo understand how a processor works you have to understand what its purpose is. The processor's job is to take data from memory (RAM), storage (hard drive), user inputs (mouse/keyboard) and then perform an operation on that data and output new data to memory, storage, or output devices (screen, speakers, etc). And at the end of the day, it's mostly just moving data from one place in memory to another. \n\nThe operation that the processor performs is a list of \"instructions\" called a program or algorithm. This is not high level code, every single instruction corresponds to a direct action taken by the processor circuitry. It's important to understand this, because at the instruction (or \"machine\") level, you are forcing a bunch of switches into position directly with a sequence of high and low voltages. \n\nNow when I say \"a bunch of switches\" I really mean a couple million logic gates. Logic gates are the simplest digital circuits and implement the boolean expressions AND, OR, and NOT. We use these operations to define and build more complex ones like addition and negation, even bit shifting (move all the bits to the left or right). Once we have those operations, we have subtraction (negation then addition), and multiplication (repeated additions and shifting). We can build up and implement all these operations in a special circuit that forms the basis of the processor called the **ALU** or Arithmetic Logic Unit. (We also have a thing called an FPU or Floating Point Unit, the ALU works on fixed point numbers, where we need an FPU for the floating point numbers). \n\nThe ALU usually has three inputs and one output. Two data inputs and an instruction input. Think of it like a calculator. It takes two inputs, does the operation you tell it, then gives you the output.\n\nSo the question is, where do the data inputs come from, where does the output go, and what is telling the ALU which operation to perform? The answer is the **registers** and **control unit.** Registers are tiny chunks of memory that hold onto a single \"word.\" If you have a 32 bit processor that means the registers are 32 bits \"wide.\" If you have a 64 bit processor then the registers hold 64 bits. Most processors have 16 registers. \n\nThe control unit is a bit more complex because it's the \"brains\" of the processor. It takes the instruction from the program and controls switches between the registers and the ALU. A simple code example might help you understand this:\n\n ADD $r0, $r1, $r2\n\nThis is an assembly instruction that tells the control unit to switch the data pathway so the ALU inputs are registers 0 and 1, the ALU instruction is \"ADD\" and the ALU output is switched to register 2. \n\nSo to recap, we have the ALU, registers, and control unit. The control unit handles the internal \"data path\" or the routing from the registers to the ALU, and the takes instructions from the program to send instructions to the ALU. \n\nThis is all well and good, but we're still only inside the processor. We haven't talked about how the processor accesses data from the user, memory or hard drive, or how the program is treated by the control unit. \n\nThis all has to do with memory. The processor generally has a special register called the \"stack pointer.\" It stores an \"address\" or location in memory where data lies (which is why it's called a \"pointer\" it \"points\" to data). It's the responsibility of the program to keep track of memory. Usually all the data the processor will ever need is in memory. \n\nIt also has a special layer of memory called the \"cache\" of very fast access memory. It's like RAM but costs a couple hundred bucks a gigabyte so you're lucky to have a few megabytes in the chip. In the cache we store \"program\" memory, which is the list of instructions to be executed. It is important to understand that the program memory holds the instructions as machine code *in order.* The processor has another pointer called the \"program counter\" which points to the location in program memory where the current instruction is stored. At the end of an instruction execution the processor increments the program counter so it then accesses the next instruction in program memory. What's really cool though is that like the stack pointer, the processor has direct access to the program counter which means it can execute instructions that changes its value. This is how we do things like loops in programming, you just reset the program counter to the start of the loop. You can also skip around in program memory, which is how you do things like functional programming. And because you're using very fast, random access memory for this there's usually no performance hit. \n\nLastly, I'm sure you're wondering how the processor knows to go to the next instruction. It's pretty simple, you use a clock. Each time the clock ticks, the program counter increments and this forces the control unit to execute the next instruction. You might be wondering what happens if it gets messed up and the control unit doesn't successfully execute the instruction in that clock cycle. It's called a \"hazard\" and it's really bad so people put lots of effort into writing code that's free of hazards and processor architectures that make them near impossible to happen. \n\nYou may also be wondering, is that really it? It's just a super complicated way of moving data from one place to another and *maybe* doing some math with it? And the answer is yes, that's it. Think about it, when I'm typing this the motherboard firmware is moving the data of the last key pressed and the action of the key being pressed (two data words) into memory, and Chrome is looking for the \"Key is pressed\" word, then the processor jumps to the instruction saying \"load last key pressed\" and moves it into the \"display\" program to show \"these bits at these locations.\" The whole thing is just moving data around. \n\n",
"I think the OP meant how they fundamentally compute things, not how they are made.\n\nThey are not complicated in how they work, their engineering is but the actual mechanism for calculation has been known since about 400 BC apparently. Doing it quickly was the problem. Since the time of the clock, mechanical computation has been known but the capabilities were held back until the advent of the transistor.\n\nSo how a processor works:\n\nA processor is a collection of light switches (or gears and values in a mechanical system) that are arranged into logical gates like AND, OR, XOR, NOT, etc. If you have ever played with Minecraft with mods like RedPower you know about those cool redstone gates.\n\nUsing those gates you can load information into registers. Think of them as little bowls you put marbles in representing bits.\n\nYou then dump the contents of those bowls into a channel that runs the marbles into those cool little gates and you get a result.\n\nYou can make a basic 'computer' with nothing more then Legos and a few marbles. Clockwork computations have been around since the 12th century. The big advancement, attributed to Babbage was the idea of a programmable calculating device. (See also Turing Complete Systems) but that is another discussion.\n\nSo back to the marbles. Depending on what marbles you pick depend on the route the remaining marbles take.\n\nIf the first marble is red, turn left. If the first marble is blue, turn right. Swallow that marble and pass the rest on.\n\nNow if we go left we take the marbles in the first bowl say (1 for red, and 0 for blue) 101101 and run them to a XOR gate. The next bowl (register) also goes 101001. At this point we now have 01101 and 01001 at the XOR gate. As the marbles pass the XOR gate the output becomes 00100 and those marbles roll into the third bowl.\n\nThis is basic computation. Turing, Babbage, Von Neuwmann, and others built modern processing to give us the ability to design complex routines that allow us to route those marbles around to a bunch of different gates, run some gates and routes concurrently, and even more complex stuff, but at the very core, it is very basic fundamentals. A few specialized components like addition, subtraction, multiplication, and division are collections of gates. More complex systems are usually built up from fundamental gates grouped and working together. The deepest principle is Boolean Logic or Binary Logic. Flipping light switches more or less.\n\nThe cool thing is we do this every day as part of a processor already. When you go to the grocery store and there are two lanes for groceries. The cashier rings up your stuff and it goes to one lane but if there is a special code (e.g. that bar that separates your stuff from the next person in line) then a switch is thrown and the remaining stuff gets processed down a different path. \n\nBy chaining tens of millions of those fundamental gates you can do complex calculations but again, the fundamentals are so basic you can build the basic parts on your own. It's shrinking them down and linking them together that is the hard part.\n\nAny basic book on Logic Circuits, a basic breadboard, and a electronics kits < $100 bucks and you can build nearly all the fundamental circuits used in a modern processor with a few exceptions.\n\nFor fun look up the 8086 processor (which has been recreated in minecraft on several occasions) as a good look at how modern processors work.\n",
"These answers are good, but let me try relating it to an actual 5 year old.\n\nImagine the processor is like a type of giant choose your own adventure book. It's a gigantic book, and though you might only have 32 or 64 choices to make at the beginning of the story, each unique set of choices you make at the start results in a different ending. All the billions of possible endings are already written into the processor when it's made, so all the hard work is done for you. You just choose a beginning and it (nearly) instantly gives you the ending. \n\nNow, the way the story is actually written into the processor is like a maze with special gates. When a part of the story reaches a gate, the gate automatically decides which way that part of the story will go, sometimes adding more stories to send through the maze. What comes out of the maze is the final ending, or the result of what you asked the processor to do.\n\nIn reality, each choice you make at the beginning is really an on or off electrical switch (like a light switch). So for instance, you can give the processor two numbers (say 2 and 4) and ask it to add them. This means your story choices would be 2, 4 and add. The trick here is, there is a special language/code you have to know, that lets you write any number, letter or request with just the on/off switches. This is called binary, and the book/processor is already written to understand it. \n\nSo you tell the processor 2, 4 and 'add' in its special on/off switch language and it tells you how that story ends, or in this case, the answer to your problem, 6.\n\nEdit: Rereading the question, I think and explanation of the silicon base was asked for.\n\nThe book/processor is written onto a silicon chip. The silicon is special because a maze can be drawn onto it, where electricity/stories can only travel through where the maze is drawn. The special gates are created with silicon, which has a special ability to only let electricity through under certain circumstances. These circumstances are what we use to build the book and decide which story parts go where next in the maze.",
"Everyone in this thread might enjoy reading [this](_URL_0_).\n\nA thread from /tg/ on 4chan where an anon suggests making a pocket computer out of shrunken zombies acting as simple AND/OR gates. We lovingly termed it Skeletron A.I.\n\nHilarity ensues.",
"Suffice it to say that binary numbers have exact analogies to all your usual mathematical operations. And it has been rigorously proven that any arithmetic operation with binary number can be expressed in some sequence of basic logic operations on the individual bits of the numbers.\n\nThe complexity of a CPU comes from organizing and synchronizing multiple circuits that all do relatively simple things.\n\nUnderstanding how a CPU adds two number is easy. But when you think about some instruction stored on a hard drive that is then loaded and inserted into the cpu and then the how the result is written... The cpu turns into a giant switchboard of circuits that can appear almost completely beyond comprehension.\n\n\n\n\n**Micro Architecture**\n\nOn the most basic level,a CPU reads and stores data from storage, it reads instructions (code) from memory, and it executes those instructions.\n\n\nYou can think of an instruction as a key that plugs into a slot, the instruction turns the slot and like one of those coin smushers at tourist attractions a result is returned on the other side. The CPU has multiple hard-wired circuits that compute specific instructions and each one has its own slot. For every instruction in your program there is a dedicated electronic circuit that will do the work. For efficiency, many of the actual physical circuits are shared between these \"slots\" and countless other little tricks to optimize as much as possible.\n\n The instruction itself consists of an operation code (*opcode*) that selects which slot the key should engage with, and it may pass additional information in the instruction through the door to the circuit inside.\n\nA very simple CPU could only have instructions that do mathematical operations with integers, typically then the instruction processing element is called the [Arithmetic Logic Unit](_URL_0_) and you can read the following page on how logic is used to implement [Addition](_URL_5_ )\n\n\nThis is the architecture view of the CPU\n\n**Architecture**\n\nAround this basic kernel of digital computation are hundreds of additional supporting electronic circuits that make this puppet show run.\n\nThe CPU/ALU discussed above has a clock connected to it, every fraction of a nanosecond it reads the next operation and then the logic executes it. How 32/64 bits of information representing an instruction gets into the CPU core is a very complex process involving multiple circuits that are responsible for: tracking which instructions are loaded, which are about to be loaded, loading instructions from memory.\n\n Most modern CPU's have a tiny amount of memory located on board called the [cache](_URL_10_) that stores instructions and data directly on the CPU silicon. This lets us \"ignore\" how the data actually got there (e.g. exactly how you communicate to a hard drive) because the [Memory Management Unit](_URL_7_), the [DMA Controller](_URL_1_), along with other supporting circuits take care of the logistics of getting data to the core.\n\nThousands of human-years have been put into optimizing each individual subcircuit as well as optimizing combinations of them to perform work faster. \n\n**Silicon**\n\nSo far these are all abstract concepts, the final connection to the physical comes in understanding that the most basic logic elements can be implemented as electronic circuits, and that the electrical properties of silicon based transistors make them very reliable and very fast and therefore a natural choice for implementing a massive synchronized computer. \n\nMost modern processors are implemented using the [CMOS](_URL_6_) Process, which uses a specific type of transistor called the [MOSFET](_URL_3_) to perform the electrical lifting to concretely represent this abstract logical machine. Earlier logic systems using resistor and bipolar transistors includes [TTL](_URL_2_) and [RTL](_URL_8_). \n\nCMOS has been the de facto standard for the lowest level of the electronic design since the 70's and is entirely responsible for the exponential progress of microprocessors, primarily because the logic circuits are simple, consume low power, can switch very fast (compared to other logic families), and can be made very very small. MOSFET transistors are also very simple to make using the deposition-etching paradigm used in manufacturing crystals (effectively a MOSFET is 2 overlapping bits of silicon)\n\nIt may surprise you to find out that it is mathematically proven that *every* logical operation can be rewritten to use a (more complicated sequence) of a single logical operation. In CMOS it is very common to express all logic in terms of [NAND](_URL_11_) gates, using what is called [NAND Logic](_URL_4_). \n\nTo see why NAND is so important we need to look at detail of CMOS technology, where using MOSFETS the NAND gate is the most compact (only 4 transistors) and lowest power of all logic gates you can create [CMOS NAND](_URL_9_).\n\n\n**Press a button and see it blink**\n\nThe Complexity of the CPU comes from absolute synchronicity across thousands of different subcomponents and subcircuits, but at the lowest level most circuits are relatively simple, accomplishing a single task and then stacked together like legos. The genius of a computer architecture comes in organizing a collection of well understood circuits into something that works synchronously together. Additionally, \n\n\n",
"Processors are made up of millions of transistors.\n\nTransistors are just miniature electronic relays. (a switch that is either on or off when power is either applied or removed)\n\nWith one relay you can make a 1 bit storage device (1=turn the relay on, 0 = turn the relay off) for code and data.\n\nWith two relays you can make a 1 bit adder circuit.\n\nBasically that is it, the first processors were made out of relays, the most complicated calculation you can think of can be implemented with millions of 1 bit adders and 1 bit storage devices and a list of instructions (stored in the 1 bit storage devices which connect the adders to specific data in a certain sequence).\n\nSubtract, you invert the input, multiply is a bunch of adds, divide is a bunch of adds and subtracts, sqrt(x) is just a bunch of multiples and divides, same for cos(x) (uses Taylor series) etc\n\nEverything else, pipelines, caches, floating point units etc are just made to speed things up (and are made out of transistors)\n\n1 or 0 that is all you need",
"If you're looking for a thorough but easy to follow explanation I'd recommend \"Code\" by Charles Petzold. It's a fantastic book and gives you a good basic understanding of computer architecture.",
"The best explanation I ever found was this: _URL_0_\n\n",
"Computerphile: How computers do math demonstrated with dominoes. \n\n_URL_0_\n",
"OP if you want a book that breaks it all down and is easy to understand check out the book [Code by Charles Petzold](_URL_0_)",
"Don't know if it has been posted before, but numberphile has made an [awesome video]( _URL_0_) that explains the inner workings of a processor with dominoes. ",
"Apparently this isn't an ELI5 question. I'm a CS major and it would still be hard to describe in a few sentences. \n\nThe bottom line is there are 1-2 billion transistors in a cpu, which results in a practically infinite amount of combinations of on or off. When a computer looks at all of these on and off switches it is able to do cool things, which answers the first part of your question. Translating binary into cool things is more complicated.",
"On the silicon chip are millions of tiny transistors - like tiny switches. These are arranged in configurations to make logic gates, which the manufacturers \"wire\" together to make more complex logic circuits which can follow 'instructions' held in the memory (more chips attached to the CPU). \n\nThink of it like the way pinball machines work - when the steel ball hits switches or goes through gates, it causes lights to flash, buzzers and bells and actuators etc. to be triggered, and maybe increments your score. Each switch or gate is input into a logic circuit, and the output might be to flash a light or activate a buzzer.\n\nInside the CPU, the \"wiring together\" of these logic circuits allow operations like arithmetic, or tests to be done, and also most important, the \"decoding\" of instructions stored in memory and then operation on data, also stored in memory.\n\nEach instruction is stored in memory as a number, encoded in binary (number base 2), and each number, known as an opcode, specifies a particular operation for the cpu to carry out. There are instructions for loading data from memory into special memory on the cpu called registers, and for loading data from registers into normal memory; instructions for making decisions, and instructions for performing arithmetic, and so on. Today's cpu's can perform millions of these instructions per second.\n\nExamples of instructions (not real ones, just for illustration). The pretend opcodes and their data are the number to the left. Apologies for the formatting:\n\n 5510 0001 load memory location 1 into register a\n 5511 0002 load memory location 2 into register b\n 0212 add register a to register b\n 3112 0100 compare register a and 100\n 9801 if greater, jump to end\n 5611 0003 store register b in memory location 3\n end:\n ....\n ....\n\nUsually these instructions are not written directly by humans, because they're pretty hard to write this way - we use more human friendly languages, called \"high level languages\" instead. However, people can and do write these directly sometimes, and they usually use \"mnemonics\" - short abbreviations that describe the operation required, instead. We call this low-level language \"assembly code\".\n\n\n\n",
"The answer is that they do not perform calculations in the way you think. That is what we see as being the \"result\" of what happens. what a processor does is route electrons through various types of logic gates. You provide input, example, your fingers touching the number pad on a calculator. That input is taken and broken down into logical steps that are performed by the processor. The processor generates output. The output is then translated into numbers that you see on the display. ",
"All of them miss very important levels.\n\n1. **Level 1: The Silicon.**\n\n A semi conductor is a material which can pass an electrical signal or not. Most semiconductors are \"yes or no\" devices (Diodes), but you can place semiconducting material together in a way that you have pins: An input, an output and a control. This is called a transistor, and you can control the level of electrical signal that passes through it. For our purposes, there is a kind that operates in the \"switching zone\", called a MOSFET. This is a voltage controlled voltage device, and turns on or off.\n\n By placing two of these in series between a voltage source and ground, the midpoint can be controlled to be switched to voltage source, ground, floating, or short the source and ground together.\n\n We arrange so that the input to one of these two MOSFETS is the opposite of the input to the other, so one input switches the output to high, or low voltage.\n\n This is the most simple logic gate, either a Buffer (delay) or Inverter (turns a high signal into a low signal).\n\n2. **Level 2: Logic Gates**\n\n A logic gate is a combination of MOSFETS in a manner that has a predictable and known response to input. Multiple inputs can be added. There are SIX kinds of non trivial gates able to be made with two inputs and one output. AND, OR, XOR, NAND, NOR and NXOR. These gates outputs depend if input A AND B are high, A OR B are high, A and not B (exclusive OR). The output can also be inverted for NAND, NOR and NXOR.\n\n3. **Level 3: Metastable circuits.**\n\n This is slightly complicated. In short, if you have two NOR gates, and wire the output of each to one of the inputs of the other you get something that looks like [this](_URL_1_). It doesn't look like that at all. That is an abstraction. The real circuit diagram is more like [this](_URL_0_)\n\n Abstractions are important here. Real silicon are not perfect ideal switches, but we moved up from level 1 to 2 by imagining they were. We moved from level 2 to 3 by ignoring that the switches need resistors and power and ground and various other electronic bits.\n\n But at our current level of abstraction, we have a latch. You can set it on, or reset it off. This output state will stay constant but not really. It can get confused and into bad states. So by taking two latches and putting them one after the other, we can get something called a D FLIP FLOP. The mechanics of this flip flop get rather complicated, but it basically breaks down to this:\n\n A D Flip Flop is a collection of logic gates with one input and one output. The Flip Flop also takes a \"CLOCK\" signal, a square wave. When the clock signal rises from low to high signal, the signal present on the input is then expressed as the output. At all times OTHER than the rising edge, the output is independant of the input.\n\n We have a one bit memory cell.\n\n4. **Level 4: Registers and computation.***\n\n A register is a collection of single bit memory cells that can be read out in parallel or sequential fashion. Sequential registers are not really needed atm, so we'll use parallel. Easiest way to imagine them are a bunch of coins, heads up or down in a line.\n\n See the abstractions? We went from silicon to switches, to logic gates, to memory cells, and now we're operating completely independently of the actual material of the computer. If you had enough coins, the right rules and time, you could run hello world on your kitchen table.\n\n So, a register is a memory element of fixed size, usually, 8 bits. This memory element can be connected to the input of a computational block depending on various signal switching.\n\n Lets talk about computational blocks and binary representation.\n\n Binary is a base two numerical system. It has the representation 0b00000111, which is '9' in decimal. Binary maths looks a bit weird, but behaves like normal maths.\n\n 0b00000111\n +0b00000101\n ----------\n 0b00001100\n\n 1+1 = 10. 10+10+10 = 110.\n\n Starting at the least significant bit, you go, \"Bitn input A, NXOR Bitn input B\", and put that in the same spot in the output. You then go \"Bitn input A, AND Bitn input B\" and if that is true, that is your carry signal, and that goes to your next bit. The next bit up is very similar, except you NXOR the output with the previous carry, and you decide if any 2 or more of the previous carry and your two input bits are one to form the next carry.\n\n So now we have an adder. It can add two binary represented numbers. We can also build a subtracter or multiplier with much more complicated logic gates. But the important thing is while it is complicated, we have the abstractions and tools that let us do it.\n\n5. **ALU, Control Unit, General Purpose Registers, Special Purpose Registers**\n\n Now the big boys come in. Arithmetic Logic Unit This is a configurable computational block that can perform a number of operations. It takes one input which tells it what to do, and two inputs to operate on, which are also loaded into General Purpose Register. It executes the known operation and that is placed in the output General Purpose Register.\n\n So where does does the 'what operation to do' come from? The Control unit is a large collection of logic which takes an encoded instruction. This instruction might say \"Add Register 1 and 2 and put it in 1.\" The control unit will then switch so that registers 1 and 2 are connected to the input to the ALU, and register 1 is connected to the output. It will also set signals so that the ALU does an addition.\n\n How does the Control Unit Know what do do? It reads an instruction from what is known as \"Program Memory\", usually disk. Where to read from in the memory is controlled by the instruction count register, one of the special purpose registers, which increments whenever the Control Unit has finished its previous instruction. The new memory location is then loaded into another of the Special Purpose registers for execution.\n\nSo, here we are.\n\nFive levels in, and we have:\n\n* Silicon can allow or deny electrical signals to pass through it.\n* These switches can be used to create basic logic.\n* This logic can be combined into persistent memory.\n* This memory can be fed into special logic to operate on the contents of the memory.\n* Memory contents can be operated on with special logic to control the operations on memory and how they are executed and stored.\n\nWHEW!\n\nBUT WE\"RE NOT DONE.\n\nWe're not at MACHINE CODE level. This is the most basic level. I haven't covered data memory, buses, program memory, programming, or a swathe of other, equally complex things.\n\nBut, as someone who has done a Electrical Engineering degree, and built transistors on doped silicon, and used logic gates to build adders, and then use VDHL with FPGAs to make a basic, rudimentary CPU, then learnt C to use on an ATMEGA 8, and now works for a multi national software company....\n\nGood question.\n\n**There is no explaining like you were five. Best I can give is \"explain like you're a high school graduate\".**",
"Very hard to Eli5 it, but essentially it works like a lot of switches that are really really tiny, but it's not a simple silicon chip, it's almost as complex or more complex than most factories. Here's one zoomed in: _URL_2_\n\nAt this scale it's still not easy to understand because the pieces are still too small to see, if you get close enough this is what you see:\n\n_URL_1_\n\nIn the second image there are about 5 or 6 transistors showing just in the picture, everything is made of silicon but it's kinda carved out in an intrinsic way, step by step.\n\nIn the first image you can see about 42,000,000 transistors.\n\nThe calculations are made just like any other machine with switches to change modes and values: _URL_0_\n\nthe advantage of the processor is that it's easily reprogrammable to do different stuff",
"Found [this video](_URL_0_) some time ago and I think the topic is very well explained",
"I'd like to make a book recommendation to anyone interested in an approachable in-depth explanation of simple logic processing: Code\n\nIt's seriously the best book I've read on the subject.\n\n_URL_0_",
"This isn't really a subject that can be covered in a way that an actual 5 year old can understand because the fact of the matter is that a lot of very smart people who make processors maybe don't understand every single bit of it either.\n\nBut to do my best anyway, I will explain here the basic workings of a Register Transfer Machine, which contains some of the basic functionality of a computer and lots of the basic components.\n\nYou need only one component to start off with but you will eventually need lots of this component strung together in somewhat complicated ways to do complicated things. This component can be made of whatever you like but when it is 'on' an electrical current will pass through it, and when it is 'off' no electric current will pass through. Generally we use transistors for this job nowadays but before that, we used vacuum tubes. I will say transistor in the next bit when I mean this component.\n\nLogic gates are the next level of complexity. Generally, they are made of between 2 and 8 transistors. The job here is that I will put in electrical signals, which will either be a high voltage or a low voltage, from outside the logic gate and the circuit should put out a high or a low voltage depending on the input voltages and the arrangement of the transistors. The simplest logic gate is the 'not' gate which takes one input: if the input voltage is high, the output voltage should be low; if the input voltage is low, the output voltage should be high.\n\nTwo other important logic gates are 'and' gates and 'or' gates; these both take two inputs. An 'and' gate will output a high voltage only when both its inputs are high. On the other hand, an 'or' gate will output a low voltage only when both its inputs are low.\n\nThe reason these gates are called logic gates are because they are analogous to logical statements where high voltage is analogous to saying something is true and low voltage is analogous to false.\n\nAt the next level are basic composite components. These are made up of ~5 logic gates(so between 10 and 40 transistors) and 'adder' circuits (circuits that can 'add' the value of two inputs) will come under this heading. I won't explain an adder circuit as these are readily available to see online elsewhere but these are important to the working of a processor and good examples of how we can combine logic gates to make more useful composite components.\n\nOne really important composite component is the multiplexor. The goal of the multiplexor is that I have two input voltages and I want to filter one of them out and simply look at the value of the other. but I want to be able to change which input I am looking at. To do this, I have a third input called a control. When the control is low, the multiplexor will match the value of the first input. When the control is high, the multiplexor will match the value of the second input. It might not be immediately obvious why this is useful but eventually, this will be important in something called addressing in the finished machine. This is also a component that goes into something called registers.\n\nBefore going into registers, I will explain that there exist components called flip-flops. Simply, these components have an input and a connection to a clock. When I say clock, I just mean an electrical input that changes value regularly at precise time intervals. When the clock \"ticks\"(changes value), the output of the flip flop may change to match the input. Until the clock ticks, however, the output of the flip-flop will remain the same, no matter if the input changes.\n\nThe goal of a register is to be able to give the signal for this register to accept a high or low voltage and then, until I give the signal again, constantly output the high or low voltage given before. Registers are made up of a flip-flop and a multiplexor. The flip-flop stores the value that we want the register to put out. The multiplexor decides whether we should update the value of the register or keep the signal the same. The way it does this is that we connect the output of the flip-flop into the first input of the multiplexor and leave the second input of the multiplexor open to accept new values. This way, while the control on the multiplexor is low, the flip-flop's value will feed-back into itself. When the control is high, the flip-flop(and so the register circuit as a whole) will take the value of the second input.\n\nRegisters are really important in the operation of processors, they are used to store values used in calculations as well as the results of those calculations.\n\nThe final thing to explain is that a Register Transfer Machine is made up of three components: a register file, containing a bank of register units to contain values to be used in calculations and the results of said calculations; an arithmetic or logic unit, collections of circuits to be used to calculate results (including adder circuits); and a series of connecting wires called 'buses'; there are three buses: data bus, address bus, and control bus. Data buses, unsurprisingly, carry the actual values of the registers and calculations. Address buses indicate which registers to use to get input values and which register to store the result in. Control buses decide which operation to perform.\n\nIn early machines, I might manually change values on the control and address buses to achieve the desired calculations but this quickly becomes tedious and highly inefficient. So, instead, I create a control unit which generates these signals for me.\n\nAnd fundamentally, that's how a processor works.",
"\"simple\" silicon chip\n\nMicroprocessors are the most complex manufactured item in the history of mankind",
"Simple answer: By giving it electricity.\n\nImagine a CPU is a bowl of spaghetti, but starts with one strand and splits into millions at the other end like a tree.\n\nBut it's a metal tree so you can put electricity through it. It has 2 states, powered and unpowered, or on and off, or 1 and 0. \n\nNow, imagine that when this tree makes a branch, each branch splits into a 1 and a 0 branch (one sends power and the other doesn't). \n\nWhen you look at the other end of the strand (millions of ends) you see tons of 1's and 0's. Because not all the power got all the way to the end of each path.\n\nNow imagine that this end with millions was a specific pattern, not random. So that when you applied power, the million ends created a system of 1's and 0's that actually meant something in a language you made up.\n\nLike the first 8 branch endings was 01001010 and that translated into a letter 'H' or something. \n\nNow attach a bunch of these trees together, powering them off and on really fast with a timing switch. \n\nYou then have a bunch of 'places' to hold 'data' in the form of characters. Just by powering something on and off really fast.\n\nSo when you look at the millions of trees with millions of branches, imagine some are looped up in a way that they continue to hold the same 1's or 0's no matter what the state of the original power timing. That is sort of like memory.\n\nNote: This is simplified to the point of probably being wrong. But the concept is there.\n\nEdit: \n\nWhoops forgot the obvious at the end. Memory means you can store numbers or data, and if you can store data (like a 5 and a 7) and a character (like a + sign). You can also connect the loop branches so that 00000001 goes up by 1 binary calculation (to 00000010) each time it loops. Also you can connect the loop branches to 'send' a pattern of 1's and 0's to another bunch of places (it can then 'load' and 'save' data to other places).\n\nSo in this example you input 5 and 7 (or load them from some place you used earlier) and send 5 into the 'addition' loop for 7 loops, and each time 5 goes up by one because that is all those branches do when the power is on. So when 5 is looped 7 times, you unload it's new value to another place and have 12 stored. Thus performing a calculation. ",
"You could have just googled it \nBut you had to get 2000 upvotes didn´t you? \nActually, that seems to be the whole point of this sub",
"Lets dive right into the magical land of data.\n\nWhats the symbol for five? 5. Whats the symbol for ten? 10. But wait, isn't that the symbol for one and zero? Right, so in our numbering system, when we get to the number ten, we write the symbol for one and zero. There is no symbol for ten, we simply recycle the ones we already have. Because of this, we call our numbering system \"base-ten\", or \"decimal\". \n\n\"Ones and zeros\",\"true and false\", and \"on or off\" are all terms you have probably heard before. What these all are referring to is a *different* kind of numbering system. For our decimal system, we write a '10' when we get to ten, but for binary, we write a '10' when we get to two. There is no symbol for two in binary, exactly how there is no symbol for ten in decimal. \"On\" or \"off\" simply refers to '1' or '0' in binary.\n\nJust to make sure that makes sense (as its super important):\n\n01 = one;\n\n10 = two;\n\n11 = three;\n\nMake sense? Cool (if not google \"binary\").\n\nOk, now for something completely different, but related.\n\nTheres something in computer theory called a \"logic gate\". It's a device. It has two inputs, and one output. The only input it accepts is \"on\" or \"off\", and the output is the same, \"on\" or \"off\". You might see the relation to binary.\n\nA logic gates output is based on its input. An example of a logic gate is a \"AND\" gate. When both of the inputs are on, the output is on. Otherwise, the output is off. \n\nYou still with me? Don't worry, the cool stuff is coming soon.\n\nAnother logic gate is the \"NOT\" gate. The NOT gate has one input. If the input is off, the output is on, and vice versa. The output is *not* the input. Get it? \n\nNow, if we put the input of a NOT gate on the output of an AND gate, we get a NAND gate. Creative, I know. We nerds don't get out much. Anyways, try to figure out what the output would be for all the four different possible combinations of the two inputs for the NAND gate.\n\n[Anyways, heres what a NAND gate looks like drawn.](_URL_1_) \n\nNow, you have probably heard of computer memory right? [**ta da!**](_URL_0_)\n\nIt's not going to make total sense at first, but that diagram shows a memory-holder-thingamajig. Look at it for a while and try to figure out what it does. Basically it holds a \"bit\" of memory. You could say that a bit is like one digit of a binary number. You line a bunch of these in a row, and you can start holding numbers.\n\nBut what do you *do* with those numbers?\n\nThis is where it gets cool. You do math with those numbers. This next device is called an \"[*adder*](_URL_2_)\". \n\nThe gate on top is called an XOR gate, its output is on if only one of its inputs is on. If there both on or off, then the output is off. \n\nNow, make it a [little more complex](_URL_3_) and you can add multiple bits at the same time, by linking the last ones \"Cout\" to the next ones \"Cin\".\n\nCool, now we have a basic calculator. How can we turn this up to 11 and make a computer?\n\nCode. \n\nNow, you know what data is, and so code is easy to explain. Its just data. Thats all it is. Really. \n\nThe reason why its different then other data though, is because the CPU interprets it as *instructions.*\n\nIf we wanted to do math for example, and we got to decide the instruction definitions we could use a system like;\n\n 00000001 = *add* a number to another number;\n\n 00000010 = *subtract* a number from another number;\n\nWith this, we can set what logic gates are being used based on data. \n\nNow, real quick, memory is organized on a computer by something called memory addresses, basically they just allow the CPU to ask for memory at a specific location.\nGenerally speaking the addresses are sized by \"bytes\" which is just another word for \"eight bits\". So if we wanted to access memory location five or whatever we could store that as '00000101'.\n\nLets go back and add some more to our table;\n\n00000011 = move this data into some location;\n\nCool, now we can say something like:\n\n\"add the number at location #5 in memory to the other number at location #7 in memory.\"\n\nBy breaking it down into:\n\n (add) (memory address #5) (memory address #7)\n\nWhich is really just\n\n 00000001 00000101 00000111\n\nPretty sweet right?\n\nBut hold on, how does the CPU know where to get its instructions?\n\nOn the cpu, Theres a tiny amount of memory, it does various things, such as hold something called the \"instruction pointer\". The instruction pointer holds the address of the next instruction, and increments itself after every instruction. So basically, the cpu reads the instruction pointer, fetches the next instruction, does it, adds one to the instruction pointer, and then goes back to step one.\n\nBut what happens when it runs out of instructions?\n\nLets go back to our table. Last time, I promise:\n\n 00000100 = set instruction pointer to address\n\nBasically, all this instruction does is set the instruction pointer to a number. You ever wonder what an infinite loop is on a computer? Thats what happens when an instruction pointer is set to instructions that keep telling the instruction pointer to set itself to that same set of instructions.\n\nThats computers in a nutshell.\n\n**tl;dr** I need to get laid.",
"I know I'm late to the party, but [I learned about computers from this 90s cartoon, The Magic School Bus Gets Programmed.](_URL_0_)",
"Imagine you and your spouse agree to turn on the light switch near your front door when either of you gets home, so that if one of you comes home and sees that the switch is on, that means that the other is already home.\n\nOn = home, off = not home.\n\nThis is a binary state. In a computer, if a circuit is on, it is represented as a 1. If it is off, it is represented as a 0. the circuit being represented as 1 or 0 it therefore called a \"bit\" (**bi**nary in**t**eger)\n\nNow imagine you replace that 1 switch with a switchboard that has 8 switches in a row. Your spouse and you can communicate a lot more information now. In fact, you can communicate **255 times** as much information. Instead of just 1 and 0, you now have 8 switches.\n\nSo information can range from\n\n[00000000] (your spouse is not home) to\n\n[00000001] (Your spouse is home) to\n\n[11111111] (Your spouse has been kidnapped by ninjas and needs you to be a bad enough dude to rescue them).\n\n255 configurations.\n\nIn a computer, when 8 bits are clustered together like this, they are called a byte. This is a basic computing concept. You can apply this concept in the context of storage, or of a CPU, and so on.\n\nNow as for how these are used to make calculations, remember the basic concept binary; either a switch is on or off. There is a nifty little type of device called a logic gate that uses binary in a very clever way. In concept, a logic gate is a little circuit that has two inputs and one output, and the output depends on the input.\n\nThere are 7 types of basic logic gates (AND, NAND, OR, NOR, XOR, XNOR, NOT). To explain the underlying idea of what their function is, I will explain only one, the AND gate. The AND gate's function is to output \"on\" if both inputs are \"on\" i.e. if both inputs are \"1\", the output will be 1, but if either or both of them are \"off\" i.e. 0, then it outputs \"off, 0.\n\nHow can the AND gate tell if both are on? Because it is physically wired that way. Here's an MSPaint example of how that effect can basically be achieved:\n\n_URL_0_\n\nIf either is \"off\" (because the circuit is broken) then current can't flow through the output, meaning the output will show as off. So the AND gate will be 1 if the first **and** the second inputs are on.\n\nThe other types of logic gates are (in terms of how they output 1)\n\nNAND: **N**ot **AND** (Both inputs are not simultaneously 1)\n\nOR (one **or** both inputs are 1)\n\nNOR (neither input is 1)\n\nXOR: e**X**clusive **OR** (only one of the two inputs are 1)\n\nXNOR (either both are 1 or both are 0)\n\nNOT, also known as an inverter, is a special one that gives the opposite output to its input. It only has 1 input (usually the output from one of the other types of logic gates).\n\nWith a combination of logic gates, you can create a more complicated logic gate called adders, and these can then be used to output the answers to mathematical inputs.",
"im taking a class on this and its complicated. and its still not explaining what we use today, just what was used and the basics of a simple processor implementation. there are still jumps in logic from electric signals to actual code that i dont understand. this is a complex topic and you might not be ok with the simple answers here, i wasnt when i asked these questions when i was 5. so, these answers are just the beginning.",
"imagine a gigantic plinko game... but one that's rigged so that if you drop balls at the top in a specific pattern, they'll switch a bunch of gates along the way down and always come out the bottom in another pattern. \n\nit's like that. you drop 0110 and 1100 into the top, 10010 pops out the bottom. expand that to millions of switches per second and getting \"hello world\" to pop out in 11010110010 form gets to be quite simple :)\n\na processor is a tiny box full of tiny switches that turn inputs into outputs like a microscopic sized epically huge plinko board.\n\nso... \"magic\" :) ",
"Eli5: imagine if you had a hundred light switches, and a hundred people, each person on each switch. all these people are standing randomly across earth. At one end, there is a light bulb, and at the other, there’s a power source. Every time the power source gets to a switch, the person will decide to flip the switch or not. If a certain combination of people switch their switches to ON, the light will turn on. Now instead of just having earth, one light, and a hundred switches; imagine there is a whole galaxy of earths. millions of lights, billions of switches. Now shrink that into the size of a penny. That’s a processor. It takes the different power sources, puts them through a few switches, and a light comes on, or turns off. That’s it. ",
"I have a midterm on this exact concept tomorrow! Reddit just made me study! There might be a god! As the ultimate procrastinator who uses reddit to distract himself I find this pleasantly ironic. ",
"There is no way to ELI5 this. The closest thing is maybe to show one of those water droplet based \"computers\" that I can't seem to find a link to right now. "
]
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"https://upload.wikimedia.org/wikipedia/commons/5/58/Nand-gate-en.svg",
"http://i.imgur.com/pAFEsit.png",
"https://upload.wikimedia.org/wikipedia/commons/thumb/f/fa/XOR_from_NAND.svg/300px-XOR_from_NAND.svg.png",
"http://i.imgur.com/bdu5kOQ.png",
"http://www.circuitstoday.com/wp-content/uploads/2009/08/semiconductor-diode-p-n-junction.gif"
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"https://en.wikipedia.org/wiki/Arithmetic_logic_unit",
"https://en.wikipedia.org/wiki/Direct_memory_access",
"https://en.wikipedia.org/wiki/Transistor%E2%80%93transistor_logic",
"https://en.wikipedia.org/wiki/MOSFET",
"https://en.wikipedia.org/wiki/NAND_logic",
"https://en.wikipedia.org/wiki/Adder_\\(electronics\\)",
"https://en.wikipedia.org/wiki/CMOS",
"https://en.wikipedia.org/wiki/Memory_management_unit",
"https://en.wikipedia.org/wiki/Resistor%E2%80%93transistor_logic",
"https://en.wikipedia.org/wiki/NAND_gate#CMOS_version",
"https://en.wikipedia.org/wiki/CPU_cache",
"https://en.wikipedia.org/wiki/NAND_gate"
],
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"https://www.youtube.com/watch?v=lNuPy-r1GuQ"
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"https://www.youtube.com/watch?v=lNuPy-r1GuQ"
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"http://www.amazon.com/Code-Language-Computer-Hardware-Software/dp/0735611319/ref=sr_1_1?ie=UTF8&qid=1447965649&sr=8-1&keywords=code&pebp=1447965653247&perid=0R8F3TKN8XGJBT2VGJW7"
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"http://petapixel.com/assets/uploads/2014/11/008.jpg",
"https://i.ytimg.com/vi/Fxv3JoS1uY8/maxresdefault.jpg",
"http://www.tayloredge.com/museum/processor/1999_Pentium4.jpg"
],
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"https://www.youtube.com/watch?v=cNN_tTXABUA"
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"http://www.amazon.com/Code-Language-Computer-Hardware-Software/dp/0735611319"
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[],
[],
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"http://en.wikipedia.org/wiki/Flip-flop_\\(electronics\\)#mediaviewer/File:SR_Flip-flop_Diagram.svg",
"http://en.wikipedia.org/wiki/NAND_gate#mediaviewer/File:NAND_ANSI_Labelled.svg",
"http://en.wikipedia.org/wiki/Adder_\\(electronics\\)#mediaviewer/File:Half_Adder.svg",
"http://i.stack.imgur.com/0rqZz.png"
],
[
"https://youtu.be/TnSLR8lUses"
],
[
"https://i.imgur.com/oxvX0Vy.png"
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||
2b229e | why do my teet hurt when i eat sugary candy (taffy, tootsie rolls...) | I bit into a doughnut with sprinkles today. I got a sprinkle right in between two teeth and my mouth lit on fire. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2b229e/eli5_why_do_my_teet_hurt_when_i_eat_sugary_candy/ | {
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"text": [
"Sounds like cavity creeps",
"Almost certainly a cavity. Your saliva dissolves the sugar and the liquid sugar mix can get into the smallest of places, so it may only be a really really tiny cavity, but still something to get checked out.",
"Hey sugar tits!"
]
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|
1pi2xf | what does it mean when someone is "in shock"? | The vid on the front page of the guy busting his leg base jumping, everyone was saying "oh he's calm because he's in shock" and I see that term thrown around a lot. What exactly does it mean? Is there a medical definition or is it just colloquial or what? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1pi2xf/eli5_what_does_it_mean_when_someone_is_in_shock/ | {
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"text": [
"The term \"shock\" is used very frequently in the medical world. It is when the organs within a person's body aren't getting enough oxygen. If a person is in shock for too long, the organs lacking oxygen will be permanently damaged, possibly leading to death.\n\nEdit: Just to be clear, I haven't seen the video mentioned by the OP. I'm referring to the term \"shock\" strictly as it is used in a medical environment. ",
"Shock is a legitimate problem and can be life threatening if not treated properly and quickly.\n\nThere are a number of causes that can trigger it, but it is basically a significant drop in blood pressure. Anxiety, chest pain, confusion, heavy sweating, shallow breathing, passing out, lack of response to trauma... all can be symptoms of shock.",
"Nobody has given a unified answer so I will try. Basically there are two kinds of shock that somebody could be referring to.\n\n/u/upvoter222, /u/someanonymousaccnt have alluded to **physiological shock**, a condition you are unable to maintain a blood pressure to the extent that it becomes life threatening. There's a huge list of causes but the familiar terms **septic shock** and **toxic shock syndrome** fit into this category.\n\nWhen you talk about somebody appearing calm after suffering some calamity, this probably refers to some form of **[dissociative episode](_URL_1_)**, which is psychological response to overwhelming pain / emotional stress / other psychological stress. Some people describe the experience as being *dream-like* or as if they were watching it *happen to somebody else* and not to themselves. Dissociative episodes are one of the symptoms of **[PTSD](_URL_0_)**, though having an episode does not necessarily mean you have PTSD. It's also an effect of certain medications. This is what I think /u/redleadereu and /u/rafflecopter are referring too.\n\nIn your example, he could very well have both: physiologic shock from blood loss and psychological shock from pain.\n\nEDIT: grammar",
"Shock is best defined as a state of hypoperfusion. Basically, in a normal state, your body moves blood around, through its network of arteries and veins, and delivers oxygen. Heart, Veins/Arteries, and Blood equal Pump, Pipes, and Pepsi. There is a problem with one of these three when a person is in shock... \nHypovolemic shock: Not enough blood. You are bleeding out. \nSeptic Shock: Systemic infection causes massive dilation of pipes, leading to relative hypovolemia. \nCardiogenic Shock: For some reason (there is a bunch) your heart isn't pumping effectively. \nNeurogenic Shock: A severe injury to the brain causes the vessels in the body to dilate, (usually below a certain point, as related to injury location). This dilation again causes a relative hypovolemia state. \nAnaphylactic Shock: This is a sever allergic reaction, which causes a massive dilation of vessels, leading to again, a relative hypovolemic state. \nPhyscogenic Shock: A shock of various causes, this can usually occur when people are scared or witness something they deem horrible or whatever. This is only temporary. Usually these people may feel dizzy, lightheaded, faint, feel the need to vomit. Best guess is it results from a rapid increase in sympathetic tone. ( basically, your fight or flight system just kicked into overdrive ) \nAlong with that, True shock can be either \"compensating\" or \"decompensating\". Compensating shock is when your body has this things happen, you are in a state of hypoperfusion, but your body is holding its own. For example, your heart rate increases, your body shunts blood to the core, you basically are dealing with the situation. At this point, a person's blood pressure usually rises. Decompensated shock is when these mechanisms start to fail. Your body can no longer keep up with the demands. Your heart can only beat so fast for so long. It is at this point that people's blood pressure usually begins to decline. This is when shit gets real. \n\nAs far as people dealing with pain, it is mainly due to the compensatory mechanism of releasing catecholomines. You're body says \"oh, shit, this is bad...\" and you get flooded with adrenaline and things. \n\nEDIT: I spelled shit wrong, and my grammar sucks. Sorry. "
]
} | [] | [] | [
[],
[],
[
"http://en.wikipedia.org/wiki/Posttraumatic_stress_disorder",
"http://en.wikipedia.org/wiki/Dissociative_disorder"
],
[]
] |
|
2l43qs | why does the us use fahrenheit when the rest of the world uses celsius? | Wouldn't it be more productive to just teach our children Celsius and save them the trouble of learning 2 different measurements of temperature? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/2l43qs/eli5_why_does_the_us_use_fahrenheit_when_the_rest/ | {
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"Because most of us are around 5 feet 7 inches and weigh around 200lbs and drive at an average speed of 50 miles per hour and have temperatures of 98.6 degrees Fahrenheit. \nThe US customary system developed from English units which were in use in the British Empire before American independence. Consequently most US units are virtually identical to the British imperial units. However, the British system was overhauled in 1824. Advocates of the customary system saw the French Revolutionary, or metric, system as atheistic. ",
"The Americans weren't invited (by the French) to the summit where the rest of The World/Europe made standardized units. \n\nI believe the podcast \"how stuff works\" had an episode about this a few years ago.",
"There is no valid reason why you shouldn't be using it.\n\nIt does carry a significant cost in both time and resources to change though. I remember when we did it in Canada. It is not a small job to change how you measure pretty much everything. That may be why you still haven't adopted it.",
"Whenever people get into a metric vs. US debate, they make it seem like Americans have no idea what the metric system is. We use both, we learn both, we just use our system more.",
"There is really no reason to change. Metric is used where necessary/practical here.",
"Let's build a cube. A meter tall (or 100 centimeters, 1,000 ..*millimeters*) wide and deep. Let's now fill it with water: Exactly 1,000 liters of water will be needed. For a weight of 1,000 kilos, or a ton. This water will boil at 100 degrees C and freeze at 0C.\n\n*oh my god metric's haaaard, man!*",
"All joking aside, Americans actually learn both, and use them interchangeably. I.e. Soda comes in 2-liter bottles, milks comes in gallons, hospitals measure liquids in cc's, and weigh/measure newborns in pounds/feet and inches."
]
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|
1meqgg | how can a country sell bonds with negative interest rate? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1meqgg/eli5how_can_a_country_sell_bonds_with_negative/ | {
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"text": [
"They can't and don't.\n\nThe thing is that inflation happens. So if the nominal interest rate on the bonds is less than the rate of inflation, the *effective* interest rate is negative. They're still a good deal, though, because cash is also affected by inflation; keeping your money in cash would just make you lose more."
]
} | [] | [] | [
[]
] |
||
62ya8y | what's the process to get into u.s from mexico legally (immigrate)? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/62ya8y/eli5_whats_the_process_to_get_into_us_from_mexico/ | {
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"text": [
"It depends. The US will offer x amount of work visas every year for jobs where there are a shortage of American workers (it could be working on farms or being a doctor), student visas and travel visas (you don't need a visa to visit the US if you are Mexican) \n\nAfter you get your foot in the door you are only allowed to stay for until your visa expires. After that you are supposed to return. If you want to legally stay, you have to apply for permanent resident status (which means you are not a citizen, but are legally entitled to stay permanently [a green card]). This can by done a few ways. First, you can apply based on family ties, if you marry an American you can apply, if you are unmarried but are the offspring of an US citizen, etc. If you posses extraordinary capabilities or training, if it is of the national interest or if you belong to a group that is being persecuted and your country's government does not have control of the situation, or are a refugee you can apply for refugee status. If you belong to the last group the state department will investigate your case and grant or deny you asylum; all require an interview with US Citizenship and Immigration Services.\n\nEmployers can also petition the government to grant x amount of visas to do x job because these jobs require workers to be in the US for extended periods of time and there are not enough people in the US that can do it.\n\nAll th is does not grant you citizenship, it grants you the right to live in the US, you do not serve on jury duty, there are certain benefits you are not eligible for but you are fully protected by the constitution (even if you are here illegally).\n\nGenerally, if you h ave no special skills then you will not be granted a green card."
]
} | [] | [] | [
[]
] |
||
bzjaoc | what is academic probation and how would somebody get it? | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/bzjaoc/eli5_what_is_academic_probation_and_how_would/ | {
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"It means your grades are shit and if you don't shape up you're out.\n\nThis is more typical in colleges or private schools since they don't want some slacker tanking their performance numbers.",
"It's when your grades are poor so the school you go to warns you. If they don't improve, there will be negative consequences such as losing funding, certain privileges, or just plain getting kicked out of school.",
"Academic probation happens to a person when their grades drop below a certain level. It usually happens when a person is really struggling with their class work, or when they simply stop doing it altogether. The GPA a person needs to drop below to be placed on academic probation varies from school to school, but it’s usually between the 2.0-2.5 range."
]
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[],
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||
1jbyki | how do we know the articles from /r/politics and anything the media shows is actually real? | Who do I believe? If I don't know the proper way to believe something? | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1jbyki/how_do_we_know_the_articles_from_rpolitics_and/ | {
"a_id": [
"cbd5lat"
],
"score": [
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"text": [
"You should treat everything you read with a healthy dose of skepticism. /r/politics is quite bad in that it commonly uses extremely biased news sources. If you read it in /r/politics, chances are it's only one part of the story. Get your news from multiple reputable sources, such as the NY Times, Al Jazeera, PBS/NPR, etc. "
]
} | [] | [] | [
[]
] |
|
43k7v1 | why would a country implement negative interest rates (ie. japan) | explainlikeimfive | https://www.reddit.com/r/explainlikeimfive/comments/43k7v1/eli5_why_would_a_country_implement_negative/ | {
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"text": [
"Yes. That's exactly why they did it. They are suffering a recession right now, and this would stimulate people to take their money and spend it, giving a boost to the economy."
]
} | [] | [] | [
[]
] |
||
1llu2k | why do humans drink so much water when compared to cats/dogs? | I saw a video of a cat drinking water yesterday, and the cat was there for ~2 mins, just lapping up water. The structure of cats/dogs is pretty much the same compared to humans, right? What fundamental difference do cats/dogs have which allows them to survive with such little water. | explainlikeimfive | http://www.reddit.com/r/explainlikeimfive/comments/1llu2k/eli5_why_do_humans_drink_so_much_water_when/ | {
"a_id": [
"cc0i7cn"
],
"score": [
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"text": [
"Humans sweat while most other animals with fur/feathers don't. Obviously you need to replace the moisture lost by sweating. \n\nEfficency of our bodies is another issue. Some animals have more efficient kidneys that concentrate urine stronger than humans. This means they need less water to carry away waste."
]
} | [] | [] | [
[]
] |
Subsets and Splits