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jipcbw | Why do we pay for cable television when they run commercials which can fund them? | Technology | explainlikeimfive | {
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"Originally you paid for cable and the channels didnt have ads. Of course, the companies always are looking for more money, so they just started putting in ads and saying cable was just more reliable signal, not ad free",
"Cable channels actually pay the cable *companies* to carry their channels. Comedy Central writes a big check to Comcast every month for the pleasure of appearing on Comcast's lineup. That, and the subscription fees, is how Comcast makes its money. Comedy Central can either run ads or charge a fee like HBO. That's how they make their money. So, really, what you're getting from Comedy Central is \"free\" programming that is not beholden to the broadcast standards that ABC, CBS and NBC live with. It allows Comedy Central to take risks and do more interesting things."
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jipfy7 | Why do pictures look sharp when you take them, but then do turn out blurry even when the camera is stable? | Technology | explainlikeimfive | {
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"If your photos are turning out blurry either the camera moved or the subject moved. A perfectly stable camera and a perfectly stable/fixed subject won't result in a blurry photo. I have a feeling your question is centered on digital photography with a smartphone camera (though feel free to correct me if you're asking about DSLR or film cameras) so the real answer here is: the preview of the photo on the smartphone screen looks sharp because you're looking not at the end result but a live video feed from the smartphone camera to the screen. When you take the photo there is a fraction of a fraction of a second where, essentially, one of the \"frames\" of that video feed is saved as a high resolution photo. If the lighting isn't perfect for the exposure time and either the subject or the hands of the photographer move *at all* during that fraction of a fraction of a second then it will result in a slightly-blurry photo. The solution to that problem is the same as it would be with any other camera: add more light, if possible, and stabilize the camera by putting it on a stand or leaning it against something and using a shutter release/timer. Even if you feel like your hands are super steady or you've braced yourself against a tree or whatnot, there's most likely a little bit of movement still and that introduces the blur."
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jirspz | Why are “green” screens green? Can they be other colours? Why does it work better if it’s green? | Technology | explainlikeimfive | {
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"The specific shade of green used in green screens is very unusual and highly visible to the human eye. This makes it easier for SFX artists to work on the scenes in production and to lessen the chance that the movie could ship with a green screen accidentally showing."
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jixzfy | When loading a page with bad internet connection, how come the ads are always fully loaded while the rest of the page is struggling to load in? | For example: when watching a YouTube video on a bad internet connection, the video stops every 2 seconds to load/render. But suddenly there is a 30sec ad, and it isn't affected by the bad connection. | Technology | explainlikeimfive | {
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"World wide sides like Youtube use an algorithm where the video you are trying to load is uploaded to the nearest server to the uploader then as viewers go, it gets uploaded to servers that are the closest to the majority of previous viewers. So if you are have issues with the video, chances are you are one of the firsts to wan to see it in your area (or some connection issues). On the other side, the ads are only local ads: so 100 ads are uploaded to the closest server, your video from a random country asks for an ad and the server randomly sends an ad first because they are located in the same servers that sent you the youtube homepage.",
"Because the ads are actually a completely different website. Think of the internet as a series of tube in this case. The flow from Youtube's \"tank\" is slow, but the flow from the ad server's \"tank\" is still flowing smoothly. Both tubes empty into the same webpage, so it's not obvious they are coming from two different places, but they are.",
"On top of what others have mentioned, namely the different contents being served by different providers and thus one may take a significantly shorter route, one also has to consider other factors. First of all, file size: If everything is collected in parallel, meaning no file has to wait for another, then, when considering the same download speed for all files, the smallest file arrives first. So maybe the ad is smaller because it is of lower quality or uses better compression. For example if you had a site with a video in the middle and ads scattered around it, then these ads will most likely be way smaller than the video. Secondly, load order: on some websites some content may not be visible because it has certain dependencies. For instance the content of a data-driven site may not show up because the site has yet to fetch, collect, the data from a different place. So you can't show the markers on an interactive map before you have the coordinates for said markers. Ads however do not depend on the data you're using, whether or not you have your marker data is irrelevant to the ads, unless you load your ads sequentially on purpose, but why would you do that. Thirdly, load priority: I don't know whether or not that can be the case regarding youtube but maybe ads have some form of load priority that basically puts ads first and content second. That could be feasible as ads are usually shorter than the content and provide a means of \"buffering\", meaning they distract the user while the video can load in the background, afterwards the full bandwidth open to be used for the video alone. Those are just some of my thoughts on this.",
"Many large services like YouTube, Netflix, Google ads, etc, use what is called a Content Distribution Network. This is a network of servers distributed geographically around the world/continent. It takes time for packets to physically move through the network. Connecting to a server on the other side of the Atlantic is obviously going to be much slower than connecting to one in the next state over. Content is copied to all the CDN servers (also called nodes) so that almost every user has a server that is geographically close to them. A CDN also helps reduce load on the primary datacenter. If everyone in the world had to get their shows directly from Netflix's main datacenter, that would create enormous strain on whatever internet connection they have. Instead, they use a high speed connection from the datacenter to the CDN nodes to copy content, then users consume the content directly from the nearest CDN node. So, why do ads load before your content? Youtube uses an algorithm to decide which videos are copied to which CDN nodes. It's impractical to copy the entire YouTube library to a CDN node, it simply requires too much storage. Instead, they only copy what users in a particular area are likely to watch. If you request a video that is *not* in your nearest CDN node, the server will request a copy from the main datacenter. The video is streamed to the node at high speed which then streams it to you as it comes in. This process is usually pretty fast, but it does take some time. Ads, on the other hand, will just about always already be in a CDN node near you. That content is always available immediately, so it tends to download before any other content. TL;DR: Ads load faster because they are on a server that is physically close to you, while your YouTube video needs to load from a server far away.",
"The ads are prioritized to load first. You’re the product, and your role is to consume the ads. The YouTube video or whatever else you want to see, that’s what draws you to that particular site — and since you want to see it, you’re willing to wait for it.",
"Imagine you’re at a restaurant and you order pancakes (your webpage content) and orange juice (ads), your waiter will take your order to the kitchen (the origin of your webpage content) for the pancakes and go pickup your orange juice at the salad bar near by (a local CDN). You can order more juice as you wait for the pancakes and the waiter will go and bring you more quickly. If more kids are at the restaurant the kitchen will be busy making pancakes, that will slow down the pancakes. Also the waiter needs to go farther to pickup the pancakes, so a combination of longer distance and busier kitchen will make your pancake deliveries slower than your orange juice.",
"Some great answers, just to add that “ads” generate money for the site owner, and usually they code the loading in such a way to either get them first (they’re generally very small content) BUT also that they have to be loaded for the rest of the page/site to render at all correctly. They do this to protect their income from displaying ads, and they get more income from click through and sales usually.",
"A web page is automatically constructed on the fly from various parts retrieved from various providers. With each part loading from different sites and using different amounts of resources, different parts will load before others. It may take a few seconds for all the building blocks to be assembled.",
"websites can be shitty and use uncompressed images, on the other hand third-party ads implemented on it are compressed by their developers to be low-weight and load very fast. moreover there can be some algorithms on website that prioritize ads to download first because each impression of ad is money that goes to website owner. i’m not a very big fan of adblock but for people with slow internet connection it can become cure. at least use it on untrusted websites"
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jiyvl1 | How does Bluetooth get in sync with videos and sound even though Bluetooth has quite a big delay? | Technology | explainlikeimfive | {
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"Cache. If/when you're streaming over bluetooth it's not in real time. It's delayed just enough to copy enough of the file to the display device so that the program can be relatively confident it will play without errors. With proper transfer speeds and compression, the delay can be almost imperceptible to the viewer, but in computer timing small portions of a second can be more than enough time to \"stockpile\" enough data to present it smoothly **grammar and spelling*",
"Bluetooth has an ideal of 34 ms of latency with an extreme at 100-300 ms. Usually it will be under 100 ms though. Our brain tolerates up to 45ms pre-audio and 125ms post-audio without noticing an issue and we can often tolerate larger numbers while just noticing that there is lag. In short: Bluetooth latency is generally within our brain's tolerances and thus we're good. ;-) Claim 1: [ URL_0 ]( URL_1 ). Claim 2: [ URL_3 ]( URL_2 )."
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"https://www.headphonesty.com/2020/07/fix-sound-delay-bluetooth-headphones/#:\\~:text=In%20a%20wireless%20connection%2C%20Bluetooth,audio%20signal%20to%20the%20receiver",
"https://www.headphonesty.com/2020/07/fix-sound-delay-bluetooth-headphones/#:~:text=In%20a%20wireless%20connection%2C%20Bluetooth,audio%20signal%20to%20the%20receiver",
"https://support.biamp.com/Tesira/Video/Video_and_network_latency#:~:text=In%20general%2C%20the%20audio%20can,and%20distracting%20for%20most%20people",
"https://support.biamp.com/Tesira/Video/Video\\_and\\_network\\_latency#:\\~:text=In%20general%2C%20the%20audio%20can,and%20distracting%20for%20most%20people"
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jj12no | why most software these days take a huge amount of ram more than 60% just to run basic stuff? for example like most browsers? | i remember in 2009 when 2GB of ram was enough to run anything and i had no problem but today even with 12GB 20% of them go to OS by default so what gives? | Technology | explainlikeimfive | {
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"Websites have to be more responsive because studies show that if things hang for more than half a second, the user is more likely to close the tab or click \"back\" and move on to something else. To help be more responsive, some websites are constantly preloading information you might need so you don't wait after you click. GMail is an example; even when not connected to the internet, you can view the first X messages in your inbox despite never having opened them before. All that is in your RAM. Memory leaks can also be an issue. Badly written software may keep storing old data but never release it and free up that RAM space until the software stops. Other user enhancements can be RAM heavy. It used to be that you could only \"undo\" in Photoshop like 3 times by default. The program would have to keep multiple full copies of the last states of the image in memory, which could be massive. Now by default even more past states are kept in memory - at least 20, I believe.",
"I remember when 2 MEGABYTES of RAM was enough to run a GUI OS. Programmers are lazier. Programming languages are heavier. Libraries are larger. Things like .NET Framework and other libraries are enormous in comparison nowadays. People don't really optimise executables for space any more, only speed (which usually means keeping everything in the executable / data uncompressed and ready to just stream direct into RAM). I spent years working on a Linux distro that squeezed all kinds of functionality into a single 1.44Mb floppy disk. It wasn't hugely difficult work, but you optimised everything for space and cut out anything you didn't need. Now you leave it all in in case someone needs it and sometimes even bundle multiple copies of it for different hardware (e.g. differently optimised game textures, etc.). Nowadays, the worst culprits are actually games. 100Gb of game data is not unusual. Sometimes that's just because that's how much the data is (billions of polygons in various models, high resolution textures, etc.) but sometimes it's just because nobody ever optimised the space on disk compared to the load speed / most FPS for dozens of combinations of hardware types. Browsers load a lot of data, especially if they are on an infinite-scrolling web page that never disposes of the resources at the top of the page (\\*cough\\* REDDIT \\*cough\\*). Huge images (even if you only display them small), lots of complex layout information, etc. And a picture is worth a thousand words (quite literally... images are thousands of times larger than plain text), and so a movie is worth a thousand pictures (again, quite literally... a short video ad will take up millions of times more space than plain text). When you have 20 tabs open, with large sites, lots of pictures, videos, adverts, lots of scrolling, all your tab history stored in memory, still, etc. it quickly gets out of hand. All for the convenience of you maybe pressing the back button at some point, or in case you scroll up quick and don't want to wait for that video ad to load back in before you can see the page. We could easily go back to the old times, but you'd lose some features and programming would be a far more expensive and time-consuming process. Simplicity of programming and convenience of the user now means things take up so much more resources than they ever did before.",
"A system using more and more ram is a good thing. The slowest part of your computer is the hard drive. Even when you have an ssd. Ram is cheap these days too.",
"Optimization. It's not that back then 2GB was enough; it's that back then, 2GB was *all you had*. Everything was optimized to run on 2GB. Now that users typically have 8-16GB and beyond, programs are being optimized to use that and more. It's free real estate, essentially. And it's not like modern apps are simply bloated up; you'll find that in having that extra 10+ GB to play with, websites are a lot more robust and responsive than 11 years ago today. Users also have a lot more programs open at once now; most people have Spotify, Discord, Steam, Skype, Teamviewer, and other miscellany open up ***as soon as the computer turns on***."
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jj2r9t | how is a telescope mounted inside of an airplane able to detect water on the surface of the Moon? | Technology | explainlikeimfive | {
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"Well, first off the telescope isn’t so much inside that 747SP as mounted on a bit where half the structure has been cut away, the telescope on th SOFIA aircraft is REALLY big! Second, it isn’t looking at things in optical wavelengths of light, like how you or I see things. It looks at infrared wavelengths which give you a nice clue as to what you’re looking at. Scientists know what a water molecule looks like in infrared, and SOFIA has such a fine resolution that they can really get a good look at the wavelengths coming off the thing that SOFIA is pointing at. In fact, the water SOFIA has seen isn’t floating around freely like you find here on earth. The molecules are most likely locked up in some of the rocks on the moon’s surface. Think of it like the way that when you look at trees, you know that the tree is made of wood, but the flashes of green make you think that there will be leaves when you get closer, the other colours might suggest flowers or fruit, and the odd flash of red or grey might lead you to think that a squirrel or bird is living there. SOFIA needs to be on the aeroplane because there’s a lot of water low down in our atmosphere, so it is flown up high to be above pretty much all of it."
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jj2x5p | Why do most shotguns use a tubular magazine, while most rifles use a box magazine? Also, why do most manual shotguns use pump action, while most manual rifles use bolt action? | Technology | explainlikeimfive | {
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"There are tubular magazine rifles and box magazine shotguns, so we’re basically talking about distinctions in popularity. However, certain high-powered rifle cartridges with pointed-tip bullets aren’t considered safe to use in a tubular magazine since the tip of each bullet would press against the primer of the next. This pretty much invites a round to go off in the magazine and create a chain reaction. The other major factors for shotguns are cost and reliability. Guns have to work properly when your life or dinner depends on it. Pump action shotguns are cost-effective to produce and extremely reliable. Also, under normal circumstances, shotguns aren’t used in situations that demand rapid reloads (5-9 rounds is usually enough) so a detachable box magazine just makes the design more complicated and expensive. Also, box magazines tend to not feed shotgun shells as reliably as rifle/handgun bullets. The popularity of the bolt-action rifle boils down to reliability and accuracy. When a bolt-action’s action locks up, it becomes a very rigid unit with no moving parts, and that makes them inherently more accurate than other designs. This is crucial for the long range shooting that hunters are frequently faced with. Furthermore, bolt-actions are very easy to clean and maintain and practically never malfunction because the design is so simple. They’re perfect for the adverse weather conditions that usually happen during big game hunting seasons."
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jj3xi1 | What is "organic" about OLED technology? | I keep reading and hearing that OLED display technology stands for "Organic Light Emitting Diode". My question is what is "organic" on it? Is it some sort of "life" based material? Or the term comes from a completely different concept? | Technology | explainlikeimfive | {
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"In chemistry \"organic compounds\" are those that are made of carbon and hydrogen primarily with a few other compounds like nitrogen, oxygen, etc (there might be some exceptions) So some of the components in an OLED display will be made from such ' organic compounds ' while traditional LEDs are made from Semiconductors such as Silicon or germanium",
"It's \"organic\" in the \"organic chemistry\" definition of the word: made of a material that has carbon-hydrogen bonds. \"Organic\" as it's used in the common sense of \"alive\" is completely different than the chemistry-centic definition.",
"Organic doesn't really mean what you think it does. So yes, OLEDs use organic molecules, but what are organic molecules and what is organic about it? Think of some other context, say a crowd forms around a police officer choking out a suspect - to use a modern example. That crowd formed *organically*, in other words they organized without an external force or organizing energy making them do it. An organic molecule is just that, a molecule that can and does bond easily under normal conditions. You can make iron bond with other elements and create metallic alloys with it, but that isn't an *organic* process. In organic Chemistry, Carbon is a very promiscuous atom, it will bond with a lot of things easily including itself. It will bond readily with hydrogen, oxygen, nitrogen, and sulfur. Biological processes take advantage of these properties because you can readily change those molecules. This is why we so readily define 'organic' with life, because life is basically a self continuing number of organic chemical manipulation.",
"Organic in this context refers to organic chemicals. Organic chemicals are any chemical that contains carbon (It does not need to come from an organism). To put simply, OLED is made by printing this organic chemical on a sheet. A little more complex than that but that's the idea."
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jj4nbi | Why do Zoom, Skype, Teams, etc all open via the browser first, then the client? | So using Zoom for work meetings and whatnot nowadays. When I click "Join Meeting" it opens a web browser first, which then asks me if it's ok to open Zoom. Why doesn't it just open Zoom directly? | Technology | explainlikeimfive | {
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"The link you clicked on is an HTTP (hypertext) link...your computer is programmed to open those with a browser. All computers, basically, know how to handle an HTTP link. The browser then looks at your machine and says \"Oh, you've got Zoom, let's open that.\" If you don't have Zoom (or whatever) it prompts you to download it. This means that the link will basically work for everyone, regardless of whether you've got the software installed or not. It's possible to write a link that opens things other than a browser; the \"mailto:\" link is also very common and opens your email program. But nobody, so far, has standardized on a link type specifically for telecommuting apps and, even if they did, it would be a while before you could count on everybody's computer supporting them, and they'd be different for every app (we haven't standardized a videoconference protocol that's in wide use...yet). You'd message a link like that to a friend and your computer wouldn't know what to do with it...most computers will ask you how to open things they don't recognize, but if you don't already have the app installed you may not know what to pick or where to get it. Basically, doing it via HTTP link makes it really user friendly for basically everyone, albeit at the cost of an extra click."
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jj7lsm | How does deleting data off a HDD even work? | Technology | explainlikeimfive | {
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"HDDs do not use grooves: they use magnets. Each individual \"bit\" of storage is actually a small magnetic field, and which way the magnetic field is going determines whether that's a 1 or a 0. As for deletion, you're right: just hitting \"delete\" doesn't make any physical changes to the disc: it only designates the data bits as empty, ready to be overridden by whatever new data comes along. The computer essentially just says \"ignore those bits: they're meaningless\".",
"It's stored magnetically, but you're right that it only marks an area as empty in the 'table of contents' without overwriting the actual data. That's why file recovery tools can usually get your files back if they have been deleted recently."
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jj9ham | Why is Wukong so prominent in gaming culture? | Technology | explainlikeimfive | {
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"Wukong is a character that has been passed down for centuries now in various forms of media, from his original appearance in the 16th century, to films in the 90s and now video games. When game devs need to create a variety of characters for their games they often tend to look to other game/history/tropes for inspiration. The Wukong character design is fun and interesting, so it's not much of a surprise that people would want to incorporate it into their games.",
"Journey to the West is one of the great Chinese novels and it's a really interesting story - worth a read if you've never tried it. I suppose by comparison, one could wonder why there are so many Shakespeare adaptations, or for a modern comparison, why there are so many DC/Marvel adaptations/interpretations (not conflating 16th century Chinese literature with comic books but you get the idea). Popular or interesting works are by their very nature consumed by a wide range of people. I guess lots of studios put Sun Wukong in their games for the same reason anyone puts a tribute in their game - they enjoy the source material. Enslaved: Odyssey to the West is a loose video game adaptation of the novel if you're interested. Never finished it myself but it was pretty fun!"
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jjbe6i | Why do virtual reality headsets still require people with poor eyesight to wear glasses if the “screen” is right in front of you? | Technology | explainlikeimfive | {
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"Move your head 5 cm from phone screen and try to keep it in focus. It is tiring. The headset contains lenses that cause the effective distance to the display to be much greater. This way you can keep your eyes relaxed as if the display was further away. But these lenses are made assuming normal vision. So someone with glasses will need to use extra lenses to correc their vision.",
"The headset has lenses (one for each eye) that are designed to allow people with normal vision to comfortably focus at the screen as if it was farther away. In other words, they produce a focused image at the back of your eye, when the screen is at the right distance from the lens, the lens is at the right distance from the eye lens, and the eye lens is at a comfortable focusing state. If you are near/farsighted, or has astigmatism, your eye lenses won't work with that same setup, because it can't adjust the focus (as a normal vision eye can), just like in \"real life\". I've seen VR headsets with focus adjustments, so that for a limited range you can compensate for near/farsighted, but not astigmatism (which is more than just moving the focus away or closer).",
"I mean, there are people that are farsighted and thus require an aid to see things near to them such as a screen",
"Actually focusing on a screen that is two inches from your face is almost impossible, and couldn't be done comfortably for very long, so VR headsets include lenses that cause the screens to appear as if they were 6-7 feet away. So if you have to wear glasses to focus on something at that distance, you'll need glasses when using VR."
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jjeiys | How is it that car companies can create autonomous driving vehicles, but they can’t make a seat belt that retracts consistently. | Technology | explainlikeimfive | {
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"Apples and oranges. A seat belt is mechanical, autonomous driving is programming. Seat belts aren’t meant to snap back like retracting a dog leash. If they did how many law suits about black eyes and broken noses would a car company have to deal with, it would also be more uncomfortable and cause people not to wear them.",
"The mechanism works just fine. It is you that is inconsistent, with how you trigger the retraction. Give it a little tug, let go, and she'll retract.",
"There is no profit to be made in improving something that doesn't require it. If there were monetary incentive, a better mechanism would be engineered."
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jjfzt0 | If a phone screen can have a 1080p (or even higher) display, and are magnitudes smaller than flat screen TVs, why can't flat screen TVs have much, much higher resolutions? | Technology | explainlikeimfive | {
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"They could, they make 4K flat screen tvs, and even 8K ones. The problem with having a 100 megapixel TV is that there isn't any 100 megapixel video to show on it. 4K has been around for years, and it's still not common to have 4K video sources.",
"Viewing distance is another factor. Your phone is usually within a few feet of your face. There's been lots of research on exactly when better resolution becomes meaningless, and at regular viewing distances it only takes roughly a 42\" TV to be able to fully enjoy 4k resolution. A larger TV allows you to sit further away (or alternatively increase resolution) before hitting that saturation point where more resolution won't make a difference, and a smaller TV/resolution does the opposite. That said, on a large (60\") TV with 8k resolution, you would have to sit about 2 feet away before the resolution becomes the limiting factor on quality. Same TV at only 1080p? You can sit 8 feet away and it'll look about the same as an 8k TV at the same distance. tl;dr - TVs could have much higher resolution but there isn't much need for it because you sit much further away. Computer monitors also tend to have high resolution (than equal sized TVs) because people sit closer to them than a TV."
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jjhvpl | This pole was in the way, but when zoomed in I could “see through” it | [ URL_1 ]( URL_0 ) How does this work? | Technology | explainlikeimfive | {
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"Someone explained in the comments. Basically, when a camera with a lens (pretty much all real cameras) looks at an object, the whole lens acts as a ton of tiny eyes that collect light, and that light is then assembled back into the image. If the lens is wider than the pole, then the 'eyes' on either side can actually see *past* the pole, so when the image is assembled using the light from all of these 'eyes', you get the light from the pole (what most of the 'eyes' see from that direction) plus the light from past the pole (what those few 'eyes' on the edge see from that direction)."
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jjijpy | how ssd’s and HD’s don’t loose memory when the laptop dies | I get that the use magnets (at least the ssd’s do) but how? And how does it ‘erase’ programs. AND how does magnetism turn into data? | Technology | explainlikeimfive | {
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"SSD's don't use magnets, HDD's do. SSD's use flash memory which comes in many different forms, but the basic principle is that electricity is applied to a \"cell\" to determine what data (if any) is stored in that cell. There are different ways the data is stored and obtained from SSD cells depending on the type of flash memory in use. Some flash memory is able to store a small electric charge (even when powered off) that can later be detected when electricity is applied to the cell. There are also other methods of storing data in these cells, but generally speaking they all read data by detecting where/how much electricity is coming out of the cell when you apply electricity to the cell. HDD's use magnetism. HDD's typically have 1 or more magnetic plates/disks inside them, and a head (not unlike the head on an old record player) that can detect or change the magnetic charge on a given location of the disk. The disk is spun to read data from the disk (the head detects whether the magnetic field at a given location on the disk is aligned as a + or a - and converts to a 1 or a 0). The head can also flip the magnetic field for a given location on the disk to store data. Larger HDD's use a combination of reducing the distance from 1 bit to the next bit on the disk, as well as having additional disks contained within the case itself to increase capacity. Since neither HDD's or SSD's require an outside electric charge to maintain their data (SSD's store data in the aforementioned cells, an HDD's store it by flipping magnetic fields), the data is safe regardless of the drive losing power."
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jjloy1 | - What other video platforms are available aside from YouTube? | Technology | explainlikeimfive | {
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"text": [
"Ublock origins as blocker for chrome or Firefox can fix that. If on a phone android use Firefox and then ublock extension then use the browser as your main viewer. If on iOS use brave browser."
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4
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jjnvsp | Axle Ratios: Someone I know is purchasing an F250 to tow a 5th wheel - why would they choose 4.30 Electronic Locking Rear Axle vs. 3.31 ELRA? What's the difference? | Technology | explainlikeimfive | {
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"text": [
"The Electronic Locking Rear Axle means that the differential can lock the two output shafts together, splitting the torque between the two. This is advantageous in low traction situations where one wheel might break free- robbing all the torque from the wheel that has traction. So why go go a higher gear ratio? It's about keeping the engine in the power band- the area where an engine can deliver the most power efficiently. 3.31 gear ratio means that the driveshaft needs to turn 3.31 times to turn the axle one time. By bumping this up to 4.30, the engine will need to turn faster to produce the same output speed, but it stay in its power band for longer when pulling a heavy load. This is desirable especially when climbing hills, as an engine might \"hunt\" for gears- downshifting and upshifting - if it can't decide which gear gives it the best mechanical advantage. Picture it like riding a bike. You don't use a high gear climbing a hill- you use a low gear that enables you to use less effort at the expense of pedaling faster. You expend more energy (fuel) but you don't need to exert as much force on the pedals to get the same torque.",
"Very roughly explained: 4.3 rear ratio means the output shaft, in this case, the axles to the rear wheels, will rotate once per 4.3 revolutions of the input shaft, in this case the driveshaft from the transmission/transfer case. This effectively lowers the top speed of each gear but increases the acceleration, which means torque has been multiplied compared to a lower gear ratio of 3.31. This extra torque/acceleration assists in getting heavier loads moving from a stop at the cost of fuel efficiency and theoretical top speed that gearing would allow. Even more roughly explained: You know how it's way easier to get moving from a stop in 1st gear rather than say 3rd gear? That's because 1st gear has a higher ratio than the rest. You're doing same thing by changing the ratio of the final gear that comes after the transmission. Higher ratio = more acceleration / less top speed, and vice versa. Your buddy won't need high speeds when towing, but he will need that extra acceleration"
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jjqzg1 | What is Ray Tracing in GPU | Technology | explainlikeimfive | {
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"gae8mzp"
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"text": [
"An attempt to more accurately simulate light by tracing and bouncing a bajillion lines all over the place similarly to how light would."
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3
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jjs3yi | Why do earphones stop working from one side? In the first few days/weeks, one side shuts off while the other side works perfectly for a long time. Why does this happen every single time? | Technology | explainlikeimfive | {
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"text": [
"This is flex based damage. Continued slight bending of cables very very lightly damages the cable at that point. Since the headphones constantly flail about, no two points will have similar levels of damage and one point had to give in at a given time. For it to break both sides at the same time, it needs to be damaged at the lower end of the headphones, which have a stronger cable since both sides run through it until they split.",
"Thinner wires after the split from the headphone jack, and the kids are they will both fail at some point, so one will fail first. Not sure if that would be confirmation balance or statistical something or other. Same thing like if there are more than 2 lines at the checkout the odds are good one of the other lines will go faster.",
"Everyone has an inherent habit of putting their phone or laptop etc in a relatively similar position most of the time. The same stress on the same part of the headphone will make it more likely that those bits will fail. Edit: autocorrect screwed up the their vs there",
"What a confusing set of answers. The answer is simple. The two earphones have completely separate wires going to them. Wires treated like headphones usually are will kinda inevitably break, unless they're very high quality. It would be amazingly unlikely if they would break at the exact same time. One breaks before the other because anything else would be extremely unlikely."
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jjx09h | The difference between a 256 GB microSD and a 256 GB HD | I'm just curious, disregarding speed and performance, why we wouldn't use a microSD card in something like a desktop when it takes up less space but essentially has the same amount of storage. | Technology | explainlikeimfive | {
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"Speed and performance is precisely why we don't use microSD cards, so it's a bit pointless to disregard those attributes.",
"SD Cards have to use extremely high density flash which comes with oodles of downsides They're notably more expensive per GB, slower by a significant amount, with far less write endurance meaning it'll wear out faster. SD Card interfaces were fast compared to HDDs, but are quite slow compared to modern SSDs. A UHS-III SD card tops out at 624 MB/s while a SATA 3 SSD can hit 750 MB/s, and an NVMe SSD can do 4 GB/s on an older PCI-e 3.0 based M.2 slot. That's about 8x faster and not even the best modern connection for SSDs. Currently 1TB microSD cards come in over $200 making them 2x the price of an SSD, and the one's I'm finding are just UHS-I so only 104 MB/s there The only thing they're better at is being small"
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jjxs3f | How do wireless cell phone chargers send an electrical charge to the phone battery without any wires? | Technology | explainlikeimfive | {
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"text": [
"They send a changing magnetic field, which acts like a magnet moving next to a coil and induces an electric current inside a coil in the phone, it’s not sending charge though the air, it’s moving the charges inside the phone",
"It operates through a principle called induction. A varying magnetic field can be used to transmit power. Running a current through a wire produces a magnetic field around the wire. In the same way placing a magnetic field near a wire causes current to flow in that wire. Unfortunately just placing a magnetic field next to a wire only produces a current for a short time since a steady magnetic field can't do any work. (Imagine the magnetic field like a bike pump, just pushing on the pump doesn't do anything beyond the first pump.)To do work with the magnetic field - you need to move it about. The rate of change of magnetic field and its strength affects how much work you can do (how hard and fast you pump the bike pump). A wireless charger has a coil of wire where the current alternates direction at very high frequency, this produces a magnetic field that alternates at high frequency. A coil is used because this is equivalent to a very long wire in a small space, which produces a stronger magnetic field. In the phone there is also a coil of wire, when that coil is close enough to the alternating magnetic field an alternating current is induced in the phone's coil. This current is rectified to a constant current with the phones electronics and this is used to charge the battery.",
"If you pass a magnet by a wire, the magnetic field gets caught by the wire, and is converted into an electric current. This is strongest when it's first caught. The reverse also happens. When you pass electricity through a wire, it creates a magnetic field. This field is made stronger by coiling wire, overlapping the fields into a stronger one. Now you just power one coil, which creates a field, and it can energize the second coil. Your wireless charger has a coil of wire in it. Your phone has another coil of wire in the back. URL_0 Last but not least, I mentioned the effect is strongest when it's first caught? So you can transmit more power by fluctuating the field very quickly."
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jk002g | Why is working with images in Word/Pages so awful? | Technology | explainlikeimfive | {
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"> It seems to be a symptom across word processing software This is kind of the heart of the problem here. Word is indeed a word processor with all the functionalities necessary to process text in any way shape or form. That you're able to work with images at all is a bit of an afterthought and only includes basic functionalities. > given how critical including text and images is to writing scientific and professional documents. That's usually something that can be easily accomplished with an appendix and a list of tables/figures. For anything that needs to look pretty for *publishing* actual layouting software (InDesign, QuarkXpress, hell, even Scribus might serve) will be used."
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jk0lg3 | How do we measure contents of asteroids and planets without physical interactions. | Just saw nasa found a asteroid made of metal (iron and nickel) worth a shit tonne of money. How do we know it’s made of metal and is it accurate enough to risk time/lives on obtaining in the future? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"All elements interact with electromagnetic radiation. That is just waves of energy that is all around us. These waves make up visible light, sound, colors, X-rays at the hospital and much more. Each wave is a different size (wavelength) and has a different energy value associated with it. A field of science called spectroscopy allows us to measure the way that elements interact with electromagnetic radiation. The great thing is is that each element interacts uniquely with different size waves. Space is filled with electromagnetic radiation and the asteroid is interacting with it constantly. There are fancy tools called spectrometers that can measure the waves after they interact with the asteroid. The information we gain from that interaction let’s us know what elements are present."
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jk20qz | Why does it fell like its easier to type sitting at a desk rather than sitting on a couch? | I find it easier to type at a desk rather than a couch | Technology | explainlikeimfive | {
"a_id": [
"gagk8tm"
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"text": [
"Because on a couch your body is in a different position and is relaxing. While on a desk you are sitting upright and your in the most comfortable position to work"
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jk241y | When securely erasing a hard drive, why would you need multiple passes to fully delete data? | I understand how most formatting just removes the pointers to files and tables on the disk, but wouldn’t doing a single pass of writing all 0s make it so that data is completely unrecoverable? | Technology | explainlikeimfive | {
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"Hard disks specifically are magnetic... although it stores binary data, magnetism itself is analog. If you write once you don’t necessary get rid of all residual magnetism. Also it’s important to write random data not all zeros or ones... Imagine folding a paper in a certain way, make hard creases. Now crumpled it up in a very methodical way. You can still see the original folds... now crumple it in a random way. This is better, but likely can still make out the original folds. Crumple it up randomly over and over, and you’ll find it’s much harder if not impossible to make out the original folds.",
"40 years ago the US Department of Defense wanted to come up with a standard for erasing a hard drive such that they could ensure that it wasn't possible to recover any data whatsoever from that drive. In coming up with this standard they had to take into account that they didn't know what the Soviet Union's capability to read a hard drive was. Mechanical hard drives operate by changing the magnetic field strength on a disk. If the field strength is above a certain threshold then that counts as a 1, if its below the threshold then that counts as a 0. Because there are a range of field strengths that correspond to a 1 and 0, the field strength of any given data sector on the disk can vary. The concern was that if you just write 0's to every sector on the disk then the sectors that previously held 1's may have a stronger field strength than the sectors that had previously held 0's. So someone with the resources of a national government could *potentially* build a hard disk reader that was capable of using that residual difference in the field strength to read what was previously on the disk. And the word potentially here is important - they probably can't, but it might be possible and the DoD wanted the chance of that happening to be 0%. Experiments that the DoD did showed that after 3 wipes, alternating 0's and 1's, that there was no detectible residual field strength. To account for the fact that we don't have a perfect understanding of physics, and that there may be some weird physics thing that is undiscovered in the west but known to the Soviets that would nonetheless let them read a drive after 3 wipes, the DoD set the number of wipes that you needed at 7. In 2001 they decided that 7 wipes were unnecessary and revised it to 3 wipes. 1 wipe on a mechanical drive is good enough for most people - recovering data off of a drive that has been wiped once *probably* isn't possible at all, and certainly isn't possible without an expenditure of resources that isn't practical to expend for someone trying to read your old drive. 1 wipe on a solid state drive should be fine for everyone, since solid state drives operate under different physics than mechanical hard drives. Despite that, most people just follow the DoD standard because it doesn't take that much more time to wipe the drive 3 times and who knows, maybe the Illuminati really is out to get you.",
"With magnetic hard drives, changing a zero to a one flips the magnetic field of a small portion of the disk. But magnetic fields are analog, not digital, and changing a 0 to a 1 will result in a slightly weaker magnetic field than writing a 1 to a location that always contains a 1. Someone with sophisticated forensics tools can extract deleted data by looking at the differences in the strengths of the magnetic fields.",
"A standard HDD (not SSD) keeps latent images of what was on there before. Forensic analysis of HDDs discovered a bunch of years ago that even if you overwrite it once, that with the proper analysis you can find out what was there before. I can't remember how many times you have to overwrite each bit, but in order to ensure that the latent data cannot be read. Think of it like writing on a pad of paper. You rip off the top page, but you can still see the imprint of what was on the top page on the pages underneath it for a few sheets. The only way to ensure someone can't figure out what you wrote is to scribble all over the pages."
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jk39l3 | How does Audible work? I'm old and confused | Technology | explainlikeimfive | {
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"Any book you buy get get to keep! Even if you stop subscribing to the monthly payments for credits.",
"You keep the books forever, even if you stop your subscription. If you have a library card, you can also download audio books free with the overdrive app. You can also use URL_0 to buy audio books and all the proceeds support local bookstores vs audible which goes to Bezos",
"Good answers elsewhere here, but I wanted to point out (in case you didn't know) that you can also return/exchange titles in Audible if you don't like them. I find that sometimes I just can't stand an narrator or I might get 20% into a book and find I can't continue. Audible lets you return them easily and simply get your credit back to use later. I probably return one of five titles I buy and it makes me worry much less about buying a title and not liking it."
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jk4pfe | Why does it feel like software developers change the UI for the sake of changing the UI? | Technology | explainlikeimfive | {
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"As a software engineer myself, I can almost guarantee you that there is always a product team in charge of UI/UX decisions for public-facing apps. It’s almost never the actual developer making these decisions. The exception i can think of is for a new/small company, where they’re just trying to figure things out",
"I am in the industry. These changes can happen for a huge number of reasons which aren't always apparent to the user. Let me list some reasons why: User testing. Users in a lab use the software and they don't understand something. The thing to remember here is that most old users will stick to a product whose UI changes but new users will simply delete a product they don't understand. So, what matters most is that new users understand the UI. Old users will adapt. Also, sometimes A/B testing reveals one design simply tests better than another... For no clear reason why. The cited example is Obama's campaign donation page changed their donate button's color and increased donations by a non trivial amount. Some big UI unification project. This usually works across multiple products where some company visionary wants all products to feel similar to encourage the idea of \"ecosystem.\" I use Excel which looks like Word... I feel comfortable in Microsoft's unified ecosystem and now have brand loyalty. Newness for newness sake. This takes many forms: some new UI designer boss comes in and wants to shake things up. Or they just want it to be obvious when you upgrade that something changed so you feel like you got something for your money. Or the industry trend changes... For example, flat ui is very popular now, but before that pseudo 3d was very popular. People want their UIs to look up to date. Actual added features sometimes prompt a new UI. You'd be surprised how some UIs look great with 10 buttons but adding an 11th button absolutely fucks up the entire layout, leading the UI designer to change paradigms completely. Sometimes technology changes: phone UIs are very different than mouse and keyboard UIs. How much of phone UI do you bring back to PC for familiarty sake even if it makes PC experience worse? Sometimes the engineers are at fault. Some UIs are just too hard to implement well or take way too long to write or the deadline is too soon so the engineers don't completely do everything the UI designer asked for or otherwise compromise the existing design somewhat unintentionally. But in the end, UIs are subjective. People use them and people are weird and unpredictable. The UI designers are also people who want to make their mark and guess what the unpredictable users want: not just in terms of sheer ease of use, but also emotionally.",
"I will probably come back to this later and fill this out more but basically it is a product of consumerism and marketing departments being in charge of projects. You change the UI every major version so you can have some thing to point to when you say \"NEW AND IMPROVED!!!!!!11!!!!\"... Everyone in engineering thinks it is stupid, everyone does it anyways because, well, they are in charge....",
"\"Fix it til it's broke.\" They get their next job by filling their resumes with new implementations. Nobody gets a better job by simplifying and maintaining reliability in something that is over 6 months old. We hates it.",
"I'm a software engineer, and a few times I've seen the management decide that the UI is \"old and stale\" and \"needs a refresh\". I think this is due to their viewpoint in using the thing being radically different from an actual end user's - they're often using it mainly to demo it to new prospects or, more likely, to show it off to potential investors, or just brag to their mates, and so leaping on the latest \"design trends\" probably seems important to them. Wankers.",
"I'm a senior engineer at a FAANG. Projects happen for one of three reasons: 1.) It really needs to happen. Some tea you can schedule these in if it's a big deal (like accessibility), but often you have to just kind of sneak them in under the radar. It's an important change, but often it won't be noticed. I always have a couple of these sitting around for when I'm bored and other people are distracted. 2.) Somebody from above is making you do it. Sometimes you can push back on these, but often cross-functional UX groups can push changes through in a coordinated way and they have the clout to force the issue. I usually push back on these if they're vague because by the time you get it well defined, done, and out the door the person asking for it has forgotten about it 3.) Someone is trying to get promoted. This can kind of be a rider on either of the other kinds, but sometimes a big change just exists so a chunk of the team can get promoted. I'm on two of these projects right now. Nobody asked for the change, and nobody will use it. But it's big and sexy sounding and perfectly aligned with a VP's initiative, so between the two I expect a promotion in about a year."
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jk4pg7 | How come in people’s memories video games looked super good like 10 years ago, and coming back to them now, the graphics really suck? [neuroscience] | Technology | explainlikeimfive | {
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"text": [
"Because you’re not remembering just the video aspect, but the whole experience. We tend to look at things very rosy when it’s surrounded by a great experience.",
"Because they really did look really good ten years ago. Technology changes over time, sometimes very rapidly, so today's good graphics will look terrible 10 years from now. But your memories still record your original in context memories from back then.",
"Video game graphics constantly improves, but it improves *relative to how it used to be.* Imagine you play some title in 2000. Now, a sequel comes out 4 years later with improved graphics. In fact, this new game is the best graphics you've ever seen in a video game! Jump forward 10 years without playing the game. Your memory is \"that game with amazing graphics, way better than anything else\". You don't remember the exact graphics, but you remember how you felt about it, the *experience*. If you then actually compare it to a modern game you will realise how much graphics actually have improved. Another thing is that you might not realize changes if they happen in small steps. Kind of like how you don't really notice your hair growing because you see it each day. Kind of the same with graphics, it constantly improves, and while we can see the difference when new games comes out, it's nothing compared to the difference over, say, 10 years. So we might not really realize just how far graphics have come since that nostalgic game you used to think looked pretty."
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jk7uq1 | Did ancient people technically require glasses as per modern people but couldn’t access them due to lacking technology, or has human eyesight deteriorated due to increased literacy and life expectancy? | Technology | explainlikeimfive | {
"a_id": [
"gah7wqg"
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"text": [
"Glasses are old and human eyes change with age. It’s not a modern phenomenon. One of the first ever operations was a treatment for cataracts. They basically stuck a needle in your eyeball and wiggled it around to break up the cataract. Apparently it improved things....a little"
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jk8v4u | What is GitHub? What is a Git? | Technology | explainlikeimfive | {
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"text": [
"Git is a version control system, which is used when you're working a project (usually a software project) with multiple people. Version control systems provide two main features: 1. It keeps track of all the files in your repository, and their histories. Whenever you make a change and commit it to the repository, it stores what changes you made. This way you can easily look up each file's history and what changes were made to it, and by whom. If there's a problem with a certain change, you can just revert it. 2. It lets different users work on a project together. There's a central repository on a shared server, and every programmer has their own copy of the repository on their computer. Whenever a user wants to make a change, they need to push their change to the shared server, and then all the other programmers can pull the change. If two people are working on the same code, then this would required them to *merge* the code manually. Github is a website that hosts Git repositories (i.e. Github is the shared server in the last paragraph).",
"Git is a version control system. It lets multiple people modify different versions of the same file and then merge their work together. This is extremely useful in coding, since even if two people need to modify the same file, they don't necessarily need to modify the same section of the same file. GitHub, well.. GitHub is to Git as PornHub is to Porn.",
"ELI5 answer: Git is a system that people who write code often use. But it can also be used for other projects. It's called \"version control\" because it saves all previous versions of your work. It saves as many files as you want to make sure your whole project is included. It's great for working in teams, because it has tools for combining your version with someone else's version. Git uses special commands like push, pull, merge, etc to use the tools it offers. There's a lot to learn if you want to use it! Most people type these commands in a terminal, but there are also graphical Git programs that let you use your mouse to do the same things. One key aspect of using Git is uploading your work to a server or somewhere the rest of your team can access it, so that you can share work easily. GitHub offers their server space for that purpose. You can \"push\" your work to GitHub to save a copy of it there, and you can \"pull\" work that other people have done to your computer."
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jk9j0i | Why do some captchas have to be solved several times before letting you proceed? | It's usually the "select all the bicycles" type of captchas. You solve it correctly, then another one pops up, then another...sometimes five or more times. And there's no question that I'm solving them all correctly. | Technology | explainlikeimfive | {
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"You keep getting new ones because the system is still not sure whether you're a bot or a human. The images are just a small part of all the parameters that are being considered in the background.",
"I have a similar question: why do the images sometimes feature a large image and you have to select say all the stop lights, but half the stop lights are in different squares? Seems like impossible to solve ones shouldn’t exist.",
"Typically this is because either you got the Captcha wrong, or because something thought you were solving it programmatically and not as a human. Captcha's watch things like mouse movements to see how human you are. If you moved the mouse directly to the appropriate boxes and clicked them in order, it might be questioning how human you are since that is similar behaviour to a script that might be made to look human.",
"Captchas are used for AI training, so they sometimes give you ones that it doesn’t know the answer to build a dataset of people’s answers. Basically, the first one isn’t to prove you’re human, it’s there for your free labor, so it has to give you another one to verify you’re human.",
"Probably you are not solving them correctly. If you are on your phone, try sliding your finger around over the captcha before selecting the pictures. On a laptop or pc, move your mouse around in circles before selecting the pictures. These movements can help prove that you are human because it would be difficult for a robot to mimic them. These tricks work especially well for the captcha that just has you check a box saying you aren't a robot. However, the most likely issue is that you didn't solve them correctly."
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jk9jb8 | What is middleware? | I was searching for clear definition on this can't seem to find it. Some times it is comunication between layers and other times its something with networks. | Technology | explainlikeimfive | {
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"It is essentially a broad term for anything that sits between two different pieces of software, enhancing their connectivity or functionality. And yes, it is a very vague term."
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jkayf8 | Do advertisers know when I've bought their product? If so why do they continue advertising? | Technology | explainlikeimfive | {
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"Advertisers do not know whether or not you bought the product. What they do know is exposure to thousands upon thousands will get people to expose their products and brand. As long as a couple people buy the advertised product its a win. Companies don't advertise expecting everyone to buy. Its all about exposure. More people know about a product or brand the higher chance it will get talked about amongst the viewers.",
"When marketing a product one thing they want to avoid is what's called 'cognitive dissonance' aka 'regret buying it' - the belief is that repeating the advertisements reinforces the buy decision."
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jkcf2l | Why do dishwashers take so long to clean the dishes? | This question sounds stupid but I am serious. Sometimes I open the dishwasher halfway through a cycle and everything looks pretty damn clean. Why does something that takes me five minutes to do by hand take two hours to do with a machine? It feels like a waste of resources. | Technology | explainlikeimfive | {
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"The point of a dishwasher is that it uses harsher versions of chemicals than you would be able to use when hand-washing. The little tablets aren't just soaps, they are abrasive salts and alkalis, more akin to bleach and strong chemical acids than the bubbly soapy stuff that you pour on your plates to wash them normally. This is why they a) can damage some decorative items, b) can scratch your glasses (it's the salt that does that, mainly, because there's nothing else to \"scrape\" debris off your plates in a dishwasher except water and salt), c) some things aren't dishwashable. In effect, the dishwasher is cleaning with heat hotter than you can stand to put your hand in, with chemicals that would burn you if you held them (often contained in little packets so they don't hurt you!), and fires pressurised water and salt and chemicals at the plates to wash them. The dishwasher cycle is thus more complex - usually the plates are rinsed in cold water first while the water tank inside the machine is being heated. Then the cold water is discarded and the hot tank water is brought in. The tablet / powder is released into the hot water and then the main cycle of heat / water pressure / salt / chemicals strips most of the stuff off your plate. That water might well be reheated and go through many such cycles to make the most of the chemicals in it. Then that water is drained, and plain hot water is used to rinse all the plates. This is mainly to get rid of the debris that's still sticking to them, but also to water down all the chemicals that are left on them. Hence removing them at this stage might mean they \\*look\\* clean, but they probably have chemicals on them still - chemicals that could result in chemical burns, bad smells/tastes on your plates, etc. After a couple of rinse cycles, fill, wash, drain, with plain water the plates are probably clean and don't have chemicals on them any more. At this point you might have a cycle of rinse-aid. That's a chemical designed to make the water \"non-sticky\"... so it doesn't stick to the plates in droplets. So another cycle of water, with rinse-aid, which makes the water \"slide-off\" the plates. That rinse-aid chemical is more akin to soap, so it's not as bad, but that probably needs a \"rinse\" afterwards too, to actually put the water on the plates to let it slide off. Then you'll have a drying cycle. While the plates are wet, clean but still have water sliding off them (rather than collecting in droplets, remember), you'll have a cycle where the inside of the machine is just kept hot. This evaporates whatever water is left (hopefully without stains from individual droplets), which then hits the side of the dishwasher and then drips/slides down to the bottom. This can be the longest part of the cycle. Then a \"drain\" cycle to finish, to get rid of all that extra evaporated water that's collected in the bottom out of the machine by now. You can take your plates out in the drying cycle, they'll be wet and hot. You \\*could\\* take your plates out in the rinse-aid cycle, but you'll get spotting on them and water stains. You \\*shouldn't\\* take your plates out in the main wash/rinse cycle, as they'll have chemicals on them still, and they'll spot and stain. Pretty much, there's a reason for all those different parts of the cycle. Unlike washing machines which I just don't understand how/why they are so god-damn complicated and take so long.",
"Dishwashers don't use very much water. Basically, they spray the same water around over and over again. You'd get the same effect on a sink full of dishes if you just loosely dragged a washcloth over everything a few thousand times. Yeah, the first few times you've gotten off maybe 95%, a few dozen times 99% of the junk, but that last 1% takes a lot of passes to work off, especially if its zero contact just using low pressure water spray. Or same thing if you have a spray attachment in your sink and you're cleaning a casserole dish. Yeah the first few sprays get most of it, but that last bit you could spray for hours and it won't come off.",
"Back in the 70s dishwashers had a big huge motor and a quite large heating element inside of the dishwasher. They used a bit more energy but would only run 45 minutes. Nowadays most dishwashers on the market are energy star compliant, which means they have to use a certain percentage less energy. How the manufactures get around that is by using small Motors and directing water flow at certain areas of the dishwasher during certain cycles. The dishwashers also don’t heat the water to near the temperatures that they used to so we have to use more chemicals to break down the fats and solids that are attached to the dish. So through the combination of low volumes of water and minimal heat and lots of chemicals the dishwasher cleans the dish. however The byproduct is poor washability. One of the recommendations in the new dishwashers to clean properly is to never use the normal wash cycle. This is the cycle that is used to judge whether the dishwasher is energy star compliant or not.",
"There are two ways to clean dishes. One is a lot of hot water, moderate chemistry, and a whole lot of mechanical agitation. Which was the old way, except it wasn't energy efficient and used a lot of water. The second way is more efficient chemistry that uses warm but not hot water and a lot of dwell time to let the chemicals do the work. So modern dishwashers run for a bit, let the detergents and water coat everything, stop and wait a while and repeat. The end result is less water and energy usage but longer wash cycle",
"Industrial machines wash a load of dishes in under a minute. They also cost at least 10 times as much as a home dishwasher and use different chemicals. The reason your dishwasher takes 2 hours to wash a load of dishes is because it is a slow dishwasher."
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jkdski | How is Electrical Energy actually Generated? | I know it's sometimes made via kinetic energy rotating magnets but that might be to complicated an explanation. Trying to figure out an easy way to explain the generation part to some kids! | Technology | explainlikeimfive | {
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"Electricity and magnetism are related forces. If you take a conductor, and a changing magnetic field, it will produce current in the conductor through a process called electromagnetic induction. Essentially what happens is that the electrons are attracted to the magnetic field, and that causes them to move - and current is just moving electrons. So if you take a bunch of wire and subject it to a changing magnetic field, you get electricity. The simplest generators are a static loop of wire with a rotating magnet inside of them. All you need to do is provide some sort of energy to make the magnet rotate - like a human turning a crank.",
"Kid-friendly explanation: if you move electrons near a magnet, the electons get a push. If the electrons are free to move, the push gets them moving and moving electrons is electricity. Easy source of electrons that can move: a wire. Metal has lots of electrons that are pretty easy to move around. If you hold a wire and wave it past a magnet you get electricity in the wire. Give a kid a coat hanger and a bar magnet and have them go to town, they're making electricity. A conventional power generator is just a way of moving a \\*lot\\* of wire past a \\*lot\\* of magnets, but the physics is exactly the same."
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jkec69 | What exactly is computer hacking? | Technology | explainlikeimfive | {
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"There are many ways to \"hack\" your way into a computer system. Sometimes the simplest way is to use the right password or getting direct access to the machine. The way to do this is through what is called \"Social Engineering\". Social Engineering is when you \"hack\" the people and the way people naturally are. Let me ask you, if you saw a person wearing a hard-hat and a vest on a construction site with a clipboard, do you think he belongs there? Most likely you would say yes. Here is the catch, this person could NOT belong there and is only pretending to belong there. A lot of times people are very trusting, or don't want to falsely accuse people. So some people that use social engineering are just acting the part. They will pretend they belong there, and ask very pointed questions, or be in places that are supposed to be secured because they are acting the part. Because they have gained entry to an area or near a computer, they can get physical access to a machine. It is often considered that if someone has physical access to the machine, that the machine is now considered compromised (because of ways to bypass the security of the computer). Sometimes people will write down passwords near their computer, or will use passwords that are relate to them. Social Engineering is very helpful for getting more information about a system or getting inside access. In addition to social engineering, there are other methods of attacks. Commonly, people will \"port scan\" to try and identify a computer system and/or determine what software is running and available to the outside world. Often times, specific ports numbers are used for specific programs. So when you call that port number of a computer, you can be fairly sure that it is running that program. You can then try and identify what version of the program is running. From there you can determine if certain vulnerabilities might be available to the system. If you're more advanced, you may try to discover/write your \"exploits\" for vulnerabilities that you have discovered just doing research. This is just a machine level style of hacking. There are other methods and ways to gain entry into systems. Some involve faking (spoofing) connections to systems. Others involve listening in over unsecured channels. And others involve causing confusion in systems (e.g. making 1=0 and the system then means false = true). Guessing passwords is generally a poor way to try and \"hack\" into a system because systems are getting smarter at locking those methods out. Now, as you get older, there is such a thing as ethical hacking. Applying your knowledge to helping people, and not hurting people. There are professional \"hackers\" that work for IT security teams. As more and more people use computers, the more need for secure systems. There will never be a perfectly secure system, but with good ethical hackers, you can try and stay ahead of the bad guys. Another item, hacking is about understanding the systems you are using, and how to bend those systems. It is a very creative endeavor. The more you know the rules, the more you can find loop holes in those rules.",
"There's lots of ways to get in. Sitting there guessing passwords would be a 'brute force attack' or some variation of it. This is why most systems will lock you out after a few incorrect guesses. It's an easy way to stop people from entering random things and hoping for the best. In any case, hacking is a pretty big topic, but the general idea of hacking is that it's accessing data not meant to be accessible to you."
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jkndft | If I bought a brand new laptop and didn’t use it at all, how many years later would I still be able to plug it in and have it work? What causes laptops to degrade in just a few years as we use them? | Technology | explainlikeimfive | {
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"I have a 2009 asus laptop that still works, can still run team fortress 2 and counter strike. Only the battery stopped working. Just wanted to pump up asus",
"Hard drives degrade over time and can get especially slow as they're about to fail. This is less of an issue with SSDs, which generally maintain read/write speeds until they just can't write anymore. This issue isn't so much that the physical hardware degrades (laptop batteries excepted), but is more related to how demanding programs and web content becomes over the computer's life. Content-heavy sites like YouTube or Netflix are more demanding now than they were 10 years ago and they'll be significantly more demanding 10 years from now. As new OS updates come out, they're tailored towards modern hardware. Of course they'll support older hardware within reason, but each year that passes the experience suffers bit by bit because of your machine's lack of processing power compared to more current hardware.",
"The battery would be the thing to go first as fluctuations in the ambient temperature would cause its chemistry to discharge slowly but surely, and once its so low, it damages itself by not having a charge within it, but also leaving it fully charged for the entire time can cause damage as well, so to retain its health, you'd want to cycle it down and recharge it every so often. Thermal paste applied by the manufacturer would be next as I'm not certain they thermal-cycle them from the factory, so it would dry up and crumble away like a stale cookie, making the thing run slowly and very poorly when you eventually do start using it. I'd say a year or two for the battery, three to five for the paste, and thirty for the whole thing if you just put it away and broke it out 30 years later and happened to find a working battery and reapplied thermal paste and got a storage device with the proper connections, where if you immediately used it when you bought it you might be lucky enough to get five to ten years out of it out of the box with daily heavy use, or fifteen with extremely light use, and obviously a gentle touch and probably replacing the hard drive or SSD within 3-10 years depending on its quality(higher end for the SSD, lesser for a thin laptop HDD).",
"I've had some of the earliest laptops ever made come through my shop working like a charm. I've also seen PCs from 1982 looking as fresh as the day they were made. It's clearly a bias, as only the ones built to last would live this long, but I believe they have higher-quality components (especially capacitors) likely because PC manufacture wasn't as advanced and they were being built by electrical engineers. More recent laptops are being built with lower-quality components that are expected to fail after a certain amount of time. It may not always be planned obsolescence, but consumerism drives quick device replacement so it's in the best interest of a laptop-selling business to tweak their product to the earliest acceptable failure. Many manufacturers have had whole product lines plagued with failing capacitors or other similar issues, as well. They often try to sweep these under the rug or secretly extend warranties to customers, but it would be a real risk here. So, to answer your question, it depends on the quality of the laptop you buy. As others have mentioned, the battery will be useless after as little as a year being undercharged. The first capacitor might blow after 5-10 years, but that might not be enough to kill it. I'd be willing to bet you could power it up after 15 years, but I wouldn't wager much on 20.",
"Capacitors wear over time and cycles . Tin whiskers can happen to old electronics rendering them useless",
"I accidentally leaned my laptop against a heater and it still works to this day even with its front half melted and the screen warped. So I guess depends on the laptop?",
"Most people don't clean their laptop fans. Dust build up inside beetween the fan and the heat sink. To a point where the fan is totally useless. This usually takes about 2-3 years. At that point the laptop overheats which makes the components age faster. Then the computer fails.",
"If you kept it in the box, sealed, and stored in a temp controlled environment, it can potentially be decades... the ONLY thing to worry about are the batteries. Depending on the quality and defects within the battery, lithium-ion batteries can last from a few years to decades as well. If you take it out of the box, that’s a whole different story. Depending on humidity, and temperature of the stored location, oxidation can occur. I’d say on average, it can last 5-20 years. I mean, the laptop I’m using myself is 8+ years old. Still works great.",
"Depends on how well the laptop was kept. If it was in a dry place not exposed to any elements at all. 2-5 years given what most batteries are made out of these days. Now if you are asking about just plugging it in and it working, that adds another 10+ years. One without a cmos battery installed .... indefinitely, or at least as long as you'd be around to use it I'd wager. Thought Id add that a laptop made today vs a laptop made in 1985 are two different beasts as far as build quality. 80s machines were built like brick shit houses. Closest comparison I could make today would be like a better quality 'Tough book' Today's portable PCs are made as cheaply and quickly as possible, they aren't crappy, just less planning was had during the longevity stage of conception. They do have many benefits over their predecessors though, namely weight, and power.",
"What do you mean degrade? I've used laptops for years and they perform the same. I think you are blaming this on hardware degradation when the more likely explanation is that if you plugged that laptop in and updated it, it would still run slow. You would think as technology improves that everything runs faster. Except that that capacity ends up being taken up anyway. Back in the old days of the web, webpages were pretty simple. Computers advanced, but sites run even slower now because that capacity gets squeezed even tighter. If you take a pristine laptop from 10 years ago and boot it up today, upgrade the OS, and even just load up Chrome and try to browse the web, you'll find it slow as balls. It's not just web but anything. It will still work for a while (I've heard of hardware almost 20 years old \"working\") but some things related to compatibility might not work, mostly due to software being unsupported and things being obsolete."
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jkopdw | how do smart phones know where you’re tapping on the screen? | Technology | explainlikeimfive | {
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"There are two major types of touch screens, Resistive and Capacitive. Resistive: Very cheap, old style touch screens. Imaging two thin pieces of paper very close to each other. When you press down on the screen it pushes the top layer into the bottom layer. That's how it detects touching. Not very accurate, can't do multitouch or gestures. Capacitive: More expensive, commonly found in phones today. Essentially it sends electricity through the screen in a grid like pattern. When you touch it with your finger your skin changes the electricity on the screen my conducting that electricity, which is measured, and tells the device you're touching it."
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jkpyai | Why are 32-bit PCs still being made when most programs are now strictly 64-bit? | Edit: wow that was fast | Technology | explainlikeimfive | {
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"Legacy support mostly. It's not really an issue in the consumer space, but you'd be surprised the kinds of legacy crap enterprises carry forward because upgrading would be \"too difficult\" or \"too expensive\". I know of one group in my org who still uses Access 98 databases for business-critical functions. And until recently another group used a homebrewed DOS-based application to track the last 30 years worth of worker's comp claims.",
"The comments about legacy support are correct but I can provide an additional specific: x86 Windows actually has a feature x86_64 doesn't, namely a compatibility mode for 16-bit applications. This covers most software from the 90s and early 00s. Most people who try to retain such software mistakenly conclude that the Windows iteration is the limiting factor and that Vista and XP were just more compatible, but the real issue in most cases is that the software is 16-bit and XP and Vista were overwhelmingly rolled out in x86 while 7 onwards were overwhelmingly x86_64. You can test this easily(?) by installing Windows 10 20H2 (the current release) x86 and popping in a few 90s CD-ROMs (or, in many cases, because of their lack of registry dependencies, just copying the program directory across from an existing install elsewhere). Many will still work fine. I have to to this often for retro enthusiasts with old games. (Interesting sidenote: the ones that don't work any more usually fail because of installer compatibility rather than software compatibility, that is, if they could install they would run fine, but the esoteric homebrew installer has weird dependencies that no longer function.)",
"I am having trouble finding sources, but 32 bit PCs really aren't being made any more like they used to be. [according to this article]( URL_0 ) microsoft has stopped offering the 32 bit version of their operating system for sale, meaning that last PC manufacturers are being forced to update. A good time to ask this question would have been back in 2013 after Intel's Atom branded \"Lincroft\" series was discontinued, the last 32 bit processor from Intel to be produced for desktop or laptop usage. Since then, no PC has been sold with a 32 bit processor, although some have been sold with a 32 bit operating system installed. In the peak of the transition between 2010 and 2015 there was one main reason why a manufacturer might opt for a 32 bit OS when a 64 bit one was available and that reason was disk space. There were a number of differences in size between 32 bit and 64 bit edition of Microsoft Windows, some of these were due to somewhat larger 64 bit files, but also decisions to add or remove legacy support with some features being removed or others being kept requiring duplicated 32 and 64 bit versions of parts of windows needed to run 32 bit software. The combination of these factors meant that 64 bit versions of windows would require more disk space and more memory to run. Sticking with 32 bit windows meant that manufacturers could ship less expensive systems that could run more smoothly than they could in 64 bit. In some cases netbooks would be sold which did not even meet the minimum requirements for the 64 bit edition of windows which was higher than the 32 bit edition. A minimum of 2gb of RAM and 20gb system drive was needed for the 64bit edition of Windows 7 instead of 1gb of RAM and 16gb drive necessary for the 32 bit version. Over time the capability of entry level PCs rose to 4gb of RAM where the benefits of 64bit Windows outweighed the cons and 64gb system drives where the file space became negligible. The twin introduction of the Chromebook and iPad also helped eliminate the Windows netbook market but that is another ELI5 entirely.",
"They aren't. No modern PC is 32-bit only. Probably the last Intel 32-bit stand-alone CPU was the [Intel Quark]( URL_0 ), and that wasn't really PC compatible nor meant to run PC software (it can only run some small stripped down versions of Linux and Windows). That is now discontinued. I think the only place you will find 32-bit Intel CPUs these days, is inside other Intel chips where they are using this old architecture as a small management or embedded CPU. For example, some Intel mobile modems use this, including the ones in some recent iPhones (yes, your iPhone XS/XR has an Intel CPU and runs Intel 32-bit code in there, believe it or not - in the cellular modem). If you look hard enough, you might find some ancient 32-bit processors still being produced for industrial machines, but I'm not so sure that's even still a thing. If what you're asking is why 64-bit processors can still run 32-bit software, the answer is backwards compatibility, that it is required by the 64-bit specification (the CPUs actually still boot in 16-bit mode), and that it doesn't really cost much to have 32-bit support, so there isn't much to gain by removing it."
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jkqj6j | What stops a bot from clicking the 'I'm not a robot' button. Is it just speed or something else? | Technology | explainlikeimfive | {
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"Thats the thing... nothing. Bots will usually click the box far to quickly, in a straight line (the OS doesn't actually track mouse position but it's relative movements over time). Most humans don't drag a pointer super fast, or super straight. It's not a really rock solid anti-bot, but it usually at least weeds out a majority. Making a computer move a cursor not like a computer is trickery than you'd think. Source: Self taught programmer and gaming addict what can totally click that button fast and straight enough to fail many of these \"I am not a bot\" tests. I literally just sit there and make a few circles with the mouse before clicking..."
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jkqqzd | ! What is a particle accelerator? | I remember reading in a meme on Instagram that there is one in Switzerland or something. What exactly does this do, and what purpose does it serve? | Technology | explainlikeimfive | {
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"A particle accelerator is exactly what it sounds like. It accelerates particles to near the speed of light. We do this using powerful magnets, and let the particles (neutrons, protons, electrons or whole atoms) race around in a ring several kilometers across getting faster and faster, with other particles going the other way. Then, we make the paths collide, so they smash into each other. When subatomic particles smash into each other like that, they can break into more fundamental particles. By observing what flies away from the crash, we can learn about the building blocks of the universe, and potentially make amazing discoveries.",
"It’s a big metal tube that makes little particles go super-duper-fast so that we can make them run into other super-duper-fast moving particles to learn science things.",
"It's like a big gun that shoots a tiny piece of something (a particle) really fuckin fast. Iirc It's basically a big circular track under near vacuum conditions (to eliminate air resistance) and then it uses magnets to accelerate an itty bitty piece of metal super fast around the circle",
"The Large Hadron Collider in (under) Switzerland has been well covered by u/Xstitchpixels, but smaller particle accelerators are also used in everything from old TVs (cathode ray tubes) to extremely powerful electron microscopes to x-ray and radiotherapy machines. This is because when an accelerated charged particle (usually an electron) hits a surface the \"stopping power\" releases energy in the form of visible light in a CRT-TV or x-rays/gamma rays in medical equipment."
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jkqrmj | Why can't telecom companies be compelled to stop phone scammers? | Technology | explainlikeimfive | {
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"A lot of it has to do with the underlying technologies the phone system runs on. Several of the systems were designed where trust was implied because it couldn’t be abused. From there IP dialing hooked into the older phone network and people figure out how to abuse a system that was never designed to handle all the crazy kinds of abuse scammers try to wring out of the phone system these days. The fundamental backbone of the phone system would have to result from the ground up. It isn’t just a matter of passing laws. It’s like telling someone: “that hundred old bridge that was designed for cars isn’t handling bullet trains very well. Make the existing bridge better without disrupting car or train service.” - the solution ends up being replacing the entire bridge."
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jkr3o5 | I just read an article that says scientists found a new molecule on Titan, one of Saturn's moons. It says that they saw it through the Atacama Large Millimeter/submillimeter Array of telescopes in Chile. How can this telescope see molecule that far away? | Here is the link to the article I read incase it says something that helps the explanation: URL_0 | Technology | explainlikeimfive | {
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"They used a technique called emission spectroscopy. All chemicals emit light in specific wavelengths based on their chemistry, these tend to be different from chemical to chemical. These have become pretty good markers for visually figuring out what something is made of. Even if we get a lot of other wavelengths of light by observing titan, we can still look for only the ones emitted by that chemical and if they are present, it is very likely that chemical itself is present. Fun fact: Helium was discovered this way. Helium is pretty rare here on earth and only exists trapped underground, it has a nasty tendency of escaping the Earth's atmosphere if let free. Using emission spectroscopy on the sun gave strong readings for spectroscopy of an element that no one knew anything about. This unknown element was named after the Greek god of sun Helios. Soon it was found on earth as a byproduct of radioactive decay and the emission spectrum from our experiments here matched."
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jkwefu | Why are older electronics more durable and last longer than newer ones? | Wouldn't it make sense if they kept making them strong? | Technology | explainlikeimfive | {
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"As things get more components, they have more potential points of failure. Imagine an old style coffee maker that just has the heating element in the base that powers the whole thing. As long as that heating coil works, everything works. Now get a nice fancy coffee maker that has an automatic water dispenser, bean grinder, WiFi enabled, etc. That is more parts that can fail. If every part has an average lifespan of 10 years, then the basic coffee maker has a 50% chance of working after 10 years, but the complex one has a 6.25% chance of working (each part independently only has a 50% chance of working, and you need all of them to still work).",
"A company's reputation used to be based very heavily on the durability/longevity of its product- Japanese electronics used to be revered partially for this reason. During this period, it wasn't uncommon to provide detailed schematics of the product and a parts list in the box, to help the consumer troubleshoot and repair it. Modern culture has shifted to the consumer demanding more features for less cost, and this combined with knowing that the consumer is almost always going to throw the device away instead of repairing it has given companies incentive to cut costs by scaling back the durability, longevity, and repairability of the product. It no longer has to last for decades, only for the period of time the consumer will use it before replacing it with a newer product.",
"This is impacted by survivorship bias. The old stuff you see today clearly survived, so it creates a perception that everything lasted longer, which isn't true. Quality standards have also changed and things are cheaper to make today",
"Sadly not. It makes more financial sense for the likes of Samsung to sell products with shorter lifespans because if they sell a product with half the lifespan, they can sell twice as many throughout *your* lifespan. And, while your next product might not be branded as Samsung, being such a huge manufacturer, there's a good chance your next product will feature their components, making it win-win for them.",
"Unfortunately most customers seem to prefer cheaper products over ones that last longer. The manufacturers could try to do marketing in order to change that, but they are actually making more money by selling cheaper products more often than more expensive more durable products more rarely. There are also other trends such as having slimmer phones and tablets and laptops instead of bulkier more durable ones. Old Nokia phones were indestructible, you could use the thinkpad laptops of old to bludgeon someone to death and blackberries could be thrown at the people who survived being hit with the laptop. Unfortunately nowadays we have replaced all those by devices that are much lighter and thinner. The modern stuff breaks more easily due to those limitations alone. Using cheaper materials to make them cheaper only makes them more flimsy. There is a niche market for \"ruggedized\" phones laptop etc, for people who use these devices in less than ideal environments, but even those are more flimsy than their predecessors from a generation ago, because they are built based on the normal flimsy models. Cramming more functions into devices and increasing their computing power only added more ways for things to go wrong. If all your phone could do was make phone calls that was only one function that could break. If you have a device that has taken over the job of a dozen different devices from a generation past that is just more stuff that could break. There is also a small issue that by making processors on a smaller and smaller scale, you make them susceptible to problems that older devices didn't have as much. Power consumption and heat generation also seems to have increased along the way. On the other hand devices have also increased in robustness in some ways. The almost complete elimination of moving parts in most modern devices makes them less likely to break. Stuff like more modern USB connectors like USB-C also help since the earlier version like USB micro weren't deigned to be plugged in as often and were more likely to break. All the wireless stuff like inductive charging or Bluetooth accessories also help reduce mechanical stress. If anyone really wanted to they could built some quite robust electronics with modern technologies, but that would create something few people would want to buy and fewer could afford and it would not make the device makers as much money. If you are in the rare position where you need some really robust stuff and money is not an issue you just buy some old hardware. NASA apparently is (or was) using some rather ancient ThinkPad laptops on the ISS, as they are less likely break or to fall victim to radiation damage than newer ones."
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jkwptq | When you store something in the cloud (a remote server that you can access via the internet) does it mean that if for example hypothetically the server were to be destroyed you would lose your data? | Technology | explainlikeimfive | {
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"This depends on the cloud provider and exactly where in their services the data is being stored. If it’s a service made for doing data storage, then it’s backed up. So no, a server failure of any kind will not cause your data to be lost. For services like AWS they’ll even have the backup at separate location so even the entire building could be destroyed. On the opposite side if your data was on a virtual machine meant for temp storage that you, yourself, spun up and that machine was terminated, then the data would be lost.",
"Professional cloud providers have multiple backups of all the data at multiple physical locations specifically so no single datacenter randomly blowing up/getting washed away by a tsunami causes unrecoverable loss of service. In fact if a copy server keels over, it is not unusual for the automatic systems to make another copy from the remaining ones to maintain the safety buffer. But yes, hypothetically if you clobbered all the physical servers with replicas of a specific data block at the same time, then it would be destroyed.",
"An actual cloud service, as opposed to a remote file server, should have redundancy. here is google describing their redundancy options for one of their cloud products. [ URL_0 ]( URL_0 )",
"There are three things that people can mean when they say \"The Cloud\". The first is Software As a Service. Rather than maintain your own infrastructure to run some application, you just use one that is maintained by the software vendor. Whether or not the software vendor is actually using highly available systems to ensure uptime and prevent data loss is out the window. The second are cloud providers, such as Amazon Web Services or Google Cloud Platform. These are providers that rent out basic web services such as virtual servers or storage arrays, and can do so programmatically. It is possible to set something up to be highly available and redundant in this system, and it's also possible to setup something that is not. The third are cloud native applications. These are applications designed with cloud providers in mind. The software sits on top of something that manages the cloud resources below it, and can programmatically manage resources based on the need of the application. For instance, if there is a peak in traffic to a web application, it could actually rent out more virtual servers to add to a workload cluster and spin up more instances of the application. So tl;dr: It really depends on how the software you're using is setup."
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jl2ner | What is that fuzzy feeling you get when slide your hand across one of those CRT TVs ? | Technology | explainlikeimfive | {
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"Static electricity. Those old TVs used electron guns to fire electrons at the TV screen. Sometimes this would charge the screen like a balloon rubbed against your hair and give it a slight charge which feels kinda fuzzy when you touch it."
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jl4wzq | How come new phones come out yearly but it takes games consoles 6/7 years to be developed? | Technology | explainlikeimfive | {
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"Phones generally get incrementally better every year. Consoles get several orders of magnitude better every generation. This is important because it allows game developers to know that if they spend years developing a game for the Xbox Z, it will run on every Xbox Z that is sold for the next 1-5 years. They don't have to make changes for XBox Z.1 or Z.2. They have a solid consistent target they can aim at for years at a time. They can focus on tuning their game to run on XBox Z's specific hardware because EVERY XBox Z sold for the next 1-5 years is IDENTICAL.",
"Money. Sony/Microsoft dont actually make much money from console sales. All the money comes from the games.",
"It doesn't TAKE 6-7 years. They choose to take 6-7 years because consumers won't buy a console every year and developers don't want a yearly console either. PC video card manufacturers release new cards every few months, because that model works for them, but that system means you have to make games for a dozen or more cards which is more complicated for developers. The longer a piece of hardware is out the more perceived value they get and the better devs are able to utilize it.",
"Most people wouldn't buy a $500 console if they thought it was only going to be active for a year or two. The companies take a loss on the console to put a game-delivery system into your home. But also remember there are upgraded versions of the console too, People know there was the PS4, PS4 Slim and PS4 Pro But I don't think people are aware PS4 actually has 11 different models and Xbox One has at least 9, and that's not counting just the cosmetic differences like a special Edition Spiderman case or whatever, its different hardware that came out over time."
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jlgh8b | How does a camera take long exposure photographs? I'll really need thisbecause every article I've read on it doesn't sink in! | Technology | explainlikeimfive | {
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"The shutter stays open. A usual picture, the shutter opens and closes super quick. On a long exposure. The shutter stays open longer exposing the picture to the film for a long time. Hence...long exposure.",
"The sensor is covered by a shutter. The longer the shutter is open, the longer light is hitting the sensor. Most cameras with manual controls can take exposures in preset increments up to 30 seconds, or in Bulb mode, essentially as long as the photographer wants - the shutter is held open by the photographer. Since long exposure times, especially in daylight, usually result in over exposure, you usually need a neutral density filter to limit the amount of light coming in. This is essentially just a darkened piece of glass. You also need to use a tripod to hold the camera still, otherwise the motion of the camera will blur the shot."
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jlo1fb | How do barcode scanners work? | Technology | explainlikeimfive | {
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"The scanner gun has two elements in it - a laser and an optical reader. The laser hits the bar code, and the white parts of the code reflect the laser back to the scanner to be read by the optical reader. The combination and width of the white space is very specific, so the scanner knows that a specific combination/width means a specific number. The last digit scanned is a checksum, which ensures that all previous digits were read correctly. With the number read correctly, the number is handed back to a database, which pulls up a specific record associated with that specific number."
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jlsg9n | Given the enormous difference in speed between sound and light, how is it possible that when watching a movie the audio and video are in sync? Shouldn't the light from the TV reach my eyes nearly 900,000 times faster than the sound reaches my ears? | Technology | explainlikeimfive | {
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"Yes, the light does reach your eyes faster than the sound does. However the difference in timing isn't something you can notice unless you are sitting a great distance away from the source; most people aren't viewing their screen from half a mile away. To complicate matters your brain doesn't even process visual stimulus at the same speed as auditory stimulus. Vision is much more complex so it takes slightly longer to process than sound, meaning if you are anywhere near your television that likely overshadows any difference in travel time anyway.",
"At a few meters distance, both take roughly jack all time. That is, one is pretty much zero and the other is pretty much zero*er*. Go sit a couple kilometers away from your TV with binoculars (and a pretty dope sound system) and you'll notice the difference.",
"It's an enormous difference when you're talking about enormous scales. If your TV is, say, 10 feet away from you it'll take the sound fractions of a millisecond to reach you, and it'll take the light nanoseconds (1 millionth of a millisecond) to reach you. Your ears/eyes can't distinguish that difference.",
"Never mind a movie, the same thing is true in real life. When you see lightening flash, you don’t hear the thunder till later. In fact, for every mile away that the lightening is, the thunder is delayed by five seconds. (Time it with your watch and you can tell how far away the storm is!) You can also see the same thing if you watch someone swing an axe in the distance. Fortunately, the difference is too small to notice for really close things. And even if it were noticable in theory, your brain would fix it for you because your brain is awesome at that kind of signal processing.",
"It takes light 0.0000000100069 seconds to reach you over three meter. It takes sound 0.00874635568 seconds to reach that same distance. You can't notice that difference."
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jlwhs6 | Why does 59 FPS and 60 FPS look drastically different to your eyes but in theory is just one frame apart from each other? | Technology | explainlikeimfive | {
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"Technically they don't as long as the original source is shot in a multiple of the framerate. It's barely detectible if you have very good vision. Essentially if you just double the framerate of the source video its easy as just duplicating every frame. But if the original source video needs to be converted to a slightly different framerate it has to have frames added or subtracted somehow to fill the gap, which is going to be more noticible."
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jlz578 | how is it possible for my phone to show me ads for things I’ve only ever thought about and never spoken of or searched? | So for context, I was at a club over the weekend and saw someone with a cool phone case which I recognised from a popular website. I didn’t mention it to anyone or Google it. The next day, I was on my phone and I thought to myself “what was the website the phone case was from” and remembered instantly. Seconds later I was shown an ad for that website on Instagram. How is this possible? I literally didn’t not speak or search for this website, only thought about it for 2 seconds! | Technology | explainlikeimfive | {
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"This is one of those areas where faults in human thinking take over. There is obviously no way, if what you've said is true, that the ad companies know enough about you to target you with that specific advert. So, it's likely that it's entirely a coincidence. However, human brains are not well-equipped to handle coincidences and so your brain is naturally trying to find a pattern or some meaning to this event (where none exists). As invasive as tracking and data-driven advertising is, nobody is that good at reading your mind... yet.",
"In short, your algorithms know you better than you know yourself. By using [dataveillance]( URL_0 ), companies can track and predict your activities, even down to what you might be considering purchasing. It’s scary stuff and we’re way behind on regulating how/what we allow big companies to do with our algorithms. I hope that explains it a little bit. edit to add: by scary, I mean unknown and unregulated. We are the product and companies will do anything they can to collect our data."
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jlzhni | How do computers work by using a system of zeros and ones? | Technology | explainlikeimfive | {
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"You have a small combination of 1's and 0's that make up what we call 'bits' where a combination of these bits form \"bits of information\" or \"bytes\". 01110100 for example is the letter T. A processor on a motherboard (the 'brain') has millions or billions of tiny \"doors\" that can either be opened to let through a tiny bit of electricity, which is a 1, or be closed, which is a 0. This way we can tell the computer what he has to do, and by calculating billions of these bits per second on a loop, he can translate all of these 1s and 0s into something we can see on the screen",
"On a very low level, what a computer is a is a collection of switches. The switches can be on, or off. We can store values with different arrangements of on and off switches - off off off on off off, or off off on on on on could represent different values. To make things easier though let's say 1 represents on and 0 represents off. That's where you get binary code. Binary code can represent all numbers in the form of just ones and zeros, which in computer terms translates to these switches being on and off. At the very low level, all a computer is doing is representing values, and applying instructions with those values. This is why we call it a computer - literally, it computes, it does math with numbers. But if we found a way to cram a colossal number of these switches onto a small space - say, by printing them on a tiny piece of silicon to the point where we're getting into the molecular scale - we could do basically anything we wanted with these numbers. We can do so many calculations so fast that we could have the computer represent all sorts of things, videos, software, simulations, e-mail, you know. It's more complicated than that but that's the basic gist. binary code exists at the very low-level in the processor but we don't really use it to make any programs, we have higher-level programming languages that the computer is built to translate into those very low level instructions.",
"If you're as curious about this as I once was, I strongly recommend you read the book \"Code\" by Charles Petzold. It's not too long, and it explains this concept from the ground up, starting way outside of computer science.",
"Not too sure about computer code, but I do know about data storage. Photos are actually a big spreadsheet of pixels, where each pixel can display any colour by adding different brightnesses (0-255) of red, green and blue. Each pixel then can be represented with 3 numbers 0-255, called RGB. The picture is then a very long list, of very long lists, of RGB values. Videos (without audio) are a very long list of photos."
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jlzk5c | We can stream and upload super high quality audio to and from our phones, at super high speeds, but why is actual phone call quality so much worse? | Technology | explainlikeimfive | {
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"Because calling goes over a very low speed network across the world. These other high speed networks have much higher frequencies or vibrations in the air, making it carry a lot more data. In general, higher frequency means lower range. The \"calling\" frequency has a low frequency, meaning it can only transport a little amount of data at a time, meaning your voice will be lower quality because it simply cannot process your voice in a higher quality in that limitation. This is the same reason that if you're put in hold when calling a company and they have music on the line, it sounds so awful. Try calling over Whatsapp, Facebook, FaceTime or whatever and you'll see that the quality is much better"
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jlzmvx | How do DLL-files work and what was the (historical) problem they solve? | They seem very important to a lot of software, and they are mysteriously inaccessible to the normal user. What are they about and what is the benefit of using them? Although I'm a fairly experienced computer user, I do not have much programming background and dll-files are just those weird things that I only have to deal with if a program breaks because a dll is missing, and then it's a nightmare (looking at you, cgywin). Thank you all for your insights! :) | Technology | explainlikeimfive | {
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"They are shared libraries. It's just ordinary code, like you end up with in any executable file, but put in one place that \\*any\\* program that goes looking for them can find them. The only difference with a DLL is that it publicly says \"Hey, I have a function called DrawOnScreen inside me, and another called PlaySound\" or whatever. Executables don't normally do that, but DLLs have to so that you know how to use them. This means that you have one place to go to, and everyone can use that same function inside that same DLL, without having to duplicate code. When you're programming, and you want to interact with something that's common to a lot of programs (like opening and closing files, etc.) then you would generally use a DLL. The DLL can be closed-source, it can be different for each graphics card / sound card / architecture / whatever. You very likely have no idea how it works, because it's something written by someone else and you probably won't have the source code (e.g. to Windows DLLs). But it will tell you what it has inside it, and it will have documentation that tells you what it can do and how to use it. This prevents repetition of code over and over again in every program. It stops you having to code your program against EVERY possible combination of hardware, OS, etc. (you just have Microsoft provide a standard DLL interface, and how it actually PlaySound's on that particular computer, that's Microsoft's problem, not yours). And it means that you can interact with a system that you don't know the internal details of, and don't need to know. But they are, in particular, DYNAMIC libraries - shared libraries that are loaded at run-time (rather than have to be around when you compile the program - you do need SOME parts of them at compile-time, the bits that tell you what functions they have inside them, so that the compiler knows what's going on). So your program starts and one of the first things it has to do is locate the DLL on disk, ask it what functions are available, and then work out where those functions are inside the DLL. At the lowest level, the LoadLibrary C function on Windows (dlopen on Linux) will find the library and load it into memory. And the GetProcAddress (dlsym) function will let you find out where the code you're looking for actually is in the DLL, and lets you call it directly from memory. It's more complicated than a static library, but now you can \"upgrade\" just the DLL on its own and fix problems in, say, networking, graphics, etc. without having to actually recompile every program that uses them. Imagine having to send out a new version of your program every time a driver or Windows DLL changes! So you can have a program that's 20 years old but always using the very latest \"OpenGL32.DLL\" to play games, or whatever. Historically, DLLs would cause all kinds of problems on Windows, because it didn't really lock down how to use them properly enough. So a central, core DLL that everyone uses might be in use, and then someone bundles that same DLL - but a different version - with their program, and then you end up with two different versions, and only one could be in memory at a time (because they're called the same thing), and one might be up-to-date and bug-fixed and have different code inside, and the other doesn't. One might even crash your machine because it's old and out-of-date, and the other doesn't. This used to cause MERRY HELL with programs, and installers had to learn to check versions of absolutely everything, and sometimes there was little you could do to fix it that would work on EVERYONE'S system (you want to use A.DLL... your customer has v3 installed. You need v2 for your program. v2 and v3 aren't compatible - what are you going to do? Delete his v3 and replace it with v2? You just broke some other program or even his entire system. Or leave his v3 and then your program crashes and never works because it needs v2?). Microsoft eventually fixed that, so now programs each have their own idea of what DLL they are using, so you can have multiple versions of the same DLL in memory at the same time, and one program will use v2, while another will use v3. This instead gives you security problems instead where you think you've upgraded that dodgy DLL that has a security issue, but in fact some programs are still using the old, insecure version! Cygwin, especially, suffered enormously from this. Cygwin1.dll was not on anyone's machine, obviously - Microsoft don't exactly put it into Windows. So each program that uses Cygwin MUST bundle the DLL with it. But the DLL, though versioned, was always called Cygwin1.dll. And anyone could make a Cygwin1.dll from their machine and they were often very different depending on who made them and on what machine. And say your programs loads a DLL that interacted with other DLLs that were also built with Cygwin (often badly!), and often those DLLs tried to load Cygwin1.dll as well in order to work! So you had a mess of different versions of the same DLL all trying to load for just one program, and they often interacted badly or just didn't work at all. This leads to enormous problems where vastly different versions are required, often decades different, and programs are built with the expectation that they are running on a particular version. Upgrade the system version of Cygwin1.dll and you might well break other programs. Don't, and your program won't work. If the user detects that Cygwin1.dll was the problem, they might well try and find a \"new\" version and copy it into your program folder... same problems occur. Most of the time, the fix was \"just delete all other files called Cygwin1.dll and reboot\" and then it would try to use one central shared version rather than the version bundled with the program. And the reboot was often necessary to clear out old versions of Cygwin that were still in use by other programs. DLLs exist on Linux and other systems too, where they're called shared libraries (and the same code can be inserted into your program \"statically\" (i.e. you put the code in as part of your program and it stays inside it and you never need to load a DLL), or \"dynamically\" (where it looks for the library on the computer that you run the program on every time you run that program). They work much better on other systems, which is why Cygwin in particular struggled - people programmed them as if it were a Linux shared library when in fact it ended up as a Windows one and you had problems because of the difference in the way each system handles things. Linux has well-organised shared libraries. They tend to be backwards-compatible, and they never use the same name if they're not backwards-compatible (e.g. libc5 and libc6 are entirely different shared libraries and you can't accidentally load one if you meant the other). They are generally stored in a very specific place so that they are indeed shared (and not like on Windows where almost every program has its own copy of the shared library, which defeats the point!). They can also be upgraded while programs are still using them (which Windows can't do!) - the code is replaced on disk, and the next time a program asks for that DLL, it's given the new version, while all the existing running programs that still have it open still get the old version. There's not anywhere near as many problems with shared libraries on other OS because of things like that. DLLs / shared libraries are a great idea, but if you're sloppy they turn into a problem with your program which can be a real pain to resolve (and usually the resolution is to try to \"fix\" your customer's computer so that it has the right software on it to start, which can break other things). Cygwin is a particularly sloppy example, they really should have handled it better, but they are far from alone in having DLL programs on Windows. But MinGW never had similar problems. And they were the cause of years of \"Well, it works on our development machine, there must be something wrong with your computers, you should reinstall\" problems with lazy programmers and their support departments. Source: I code cross-platform using Cygwin, MinGW and port my and other's code to/from Linux and Windows. And I manage networks, so I came across all kinds of lazy programming nightmares.",
"A lot of functionality that programs use can be shared. Things like how to read/write a file, draw something on screen, for games the entire physics engine, and so on. Instead of having to build all that code for every separate application, you put it in a pre-built *library file* (DLL stands for dynamic link library) so that programs can use that. They're basically a file with functions that other programs can use. Benefits of doing this are: * build-times are smaller, as you don't have to compile all that extra code, * the exes are smaller since you don't have to include what can be hundreds of MB of functionality. * Maintainability can be increased, since you can update the DLLs without having to rebuild every application that uses it (usually; there are exceptions). Can you imagine having to re-build and reinstall *every program* after every OS update? But the downside is the one you ran into: if a required DLL is missing, programs that use it don't work anymore. *Usually* installers include their required DLLs in their installers, but unfortunately sometimes they don't. And then you have to find out where you can get it from :(",
"A DLL is a dynamiclly linked library. This opposite to a static linked library. The difference is that a DLL can have the underlying implementation changed (say file#Write) versus statically assigning the literal writing of a file to disk in the code itself directly with file#Write. The difference is it's dynamic, which means as long as the signature is the same (call file#Write with 2 parameters, first being the filename, and second being the content), that ANY implementation that handles that could be swapped out and the program doesn't care. Write to a HDD. Write to a wall. Write text in the sky from a plane. The program only cares that it called that write fiction and it returned success. It's up to the DLL to do the underlying parts to actually write. Given a stable DLL interface you can abstract away lots of the work and focus on what your program is trying to do, and upgrade itself later as needed (cd-rw for example) without having to code the actual writing with a laser."
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jm1ml3 | How do Polygraph Tests work? | Technology | explainlikeimfive | {
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"They monitor physiological indicators such as heartrate and blood pressure. They basically measure how nervous you are. They are not reliable lie detectors.",
"Here's a summary from [ URL_1 ]( URL_0 ): > The dirty little secret behind the polygraph is that the \"test\" depends on trickery, not science. The person being \"tested\" is not supposed to know that while the polygraph operator declares that all questions must be answered truthfully, warning that the slightest hint of deception will be detected, he secretly assumes that denials in response to certain questions -- called \"control\" questions -- will be less than truthful. An example of a commonly used control question is, \"Did you ever lie to get out of trouble?\" The polygrapher steers the examinee into a denial by warning, for example, that anyone who would do so is the same kind of person who would commit the kind of behavior that is under investigation and then lie about it. But secretly, it is assumed that everyone has lied to get out of trouble. > > The polygraph tracings don't do a special dance when a person lies. The polygrapher scores the test by comparing physiological responses (breathing, blood pressure, heart, and perspiration rates) to these probable-lie control questions with reactions to relevant questions such as, \"Did you ever commit an act of espionage against the United States?\" (commonly asked in security screening). If the former reactions are greater, the examinee passes; if the latter are greater, he fails. If responses to both \"control\" and relevant questions are about the same, the result is deemed inconclusive. > > The test also includes irrelevant questions such as, \"Are the lights on in this room?\" The polygrapher falsely explains that such questions provide a \"baseline for truth,\" because the true answer is obvious. But in reality, they are not scored at all! They merely serve as buffers between pairs of relevant and \"control\" questions. > > The simplistic methodology used in polygraph testing has no grounding in the scientific method: it is no more scientific than astrology or tarot cards. Government agencies value it because people who don't realize it's a fraud sometimes make damaging admissions. But as a result of reliance on this voodoo science, the truthful are often falsely branded as liars while the deceptive pass through. > > Perversely, the \"test\" is inherently biased against the truthful, because the more honestly one answers the \"control\" questions, and as a consequence feels less stress when answering them, the more likely one is to fail. Conversely, liars can beat the test by covertly augmenting their physiological reactions to the \"control\" questions. This can be done, for example, by doing mental arithmetic, thinking exciting thoughts, altering one's breathing pattern, or simply biting the side of the tongue. Truthful persons can also use these techniques to protect themselves against the risk of a false positive outcome. Although polygraph operators frequently claim they can detect such countermeasures, no polygrapher has ever demonstrated any ability to do so, and peer-reviewed research suggests that they can't.",
"Basically What polygraphs do is measure your heart activity. When a person tells a lie their heart rate alters from the norm or in a different pattern. This is why you are asked ‘baseline questions’ they measure your heart to see how it beats when telling the truth. Later on if you are asked a question and during your response your activity changes it can be an indicator that you may be telling a mistruth. This is also the reason why polygraphs are rarely admissible in court given the fact that after training these tests can be fooled."
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jm1rq9 | What is purpose of YouTube video having 50-60fps in resolution section? | Technology | explainlikeimfive | {
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"The higher frame rates are mostly for streaming video game footage or sports which were captured and/or broadcast in a higher frame rate. ABC, FOX and ESPN broadcast in 720p 59.97fps (sometimes called 60fps). [As for why 29.97, this old eli5 tread gives a good explanation]( URL_0 )."
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jm3s0l | What does computer hacking actually look like? Movies make it seem action-packed — a lot of fast typing, on-screen visuals, and tight deadlines. But that's fake, right? Is actual hacking just writing code for hours on end? | Technology | explainlikeimfive | {
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"Not even that. The vast majority of \"hacking\" is social engineering. That is, convincing gullible people to give up their own access credentials so you can just log in like a normal employee. It's stupidly effective, AFAIK 20% of a company's employees *not* falling for a fake email from IT/a fictional guy from HR/etc. and giving out their password is considered a pretty decent record when doing a security audit.",
"> Would it just be them typing code into a terminal window? Or running scripts? More or less that. Mr Robot has a pretty decent representation of how it is in reality if a bit dramatized for the screen. However for the most part hacking is pretty boring. It's akin to trying to solve a puzzle where all you have is a terminal window, cryptic error messages, and a few scripts that may or may not do anything useful as you try to figure out how the system in question works.",
"Most hacking attempts are aimed at the weakest part of the system security. That part is the squishy sack of meat sat in front of the keyboard, particularly if they use weak passwords, use the same password for everything, send out passwords to other people, or leave them written on post-its stuck to their monitor. So if you were sat next to a “hacker” breaking into a corporate server, they’d probably just use a VPN and the regular login interface that company employees use, just with a login and password they’d acquired by social engineering. It’d be pretty boring really.",
"IANAH, just a mere software developer, but let me try to tackle this: > Would it just be them typing code into a terminal window? Or running scripts? Or navigating through folders like in a regular operating system? Yes, yes, and yes. \"Hacking\" in general is a very broad term, like \"fixing\". Alright, let's scope it down to \"fixing a car\" - there are still a lot of things that *could* be happening! In essence, though, much like fixing a car, hacking is about using either already known, or freshly acquired knowledge about how something works to reach the goal. Much like cars, computer systems are made of interplaying modules of varying complexity; and each module can be implemented in whole slew of different ways. Take wheels, for example - they can have varying width, diameter, tread, bolt pattern... Same thing, for example, with a file system - it has structure, folders and files, metadata (what was last accessed when, etc); but the details of the module is what hackers are really interested in. By exploring (majority of the time beforehand) various modules of computer systems, how they function and where their flaws lie a hacker can prepare scripts that will execute an attack - exploits, as they are called. By exploring the organization of the network during the attempted hack a hacker can figure out where sensitive data may lie, and what may be possible options/point of attack to get there. For example, accounting data of some firm may be stored on the same physical machine as the one that hosts their website (horrendously stupid, but happens!); so by attacking the website they *may* get access to the files. Or they may chose to start bombarding some poor accountant with scam emails with malware attachments, hoping it gets executed by the user and grants the attacker access. & #x200B; For faithful representations of hacking on TV, I think \"Mr. Robot\" does good enough job. It's not a fast process (at least not without due groundwork and intelligence gathering), a lot of it is automated with scripts and tools, but there's also exploratory part to the process and some decision-making involved."
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jm4g7d | explain how intel 10900k which only has 10 cores and just slightly faster single core can match the performance and sometimes outperform ryzen 3950X that has 16 cores? | Technology | explainlikeimfive | {
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"Having 16 cores doesn't help if an application is only designed to use a few of them, which describes most games. It's uncommon for consumer-level applications to make efficient use of the 32 threads that a 3950X can provide (or even the 20 that the 10900k offers). I'm typing this on a computer with a 3950X that I built for a heavily multi-threaded workload, where the 3950X handily outperforms the 10900k.",
"Can you provide an example of where this happens? Probably it's a program that doesn't use all the cores."
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jm52y6 | Why do monitors reverse colors when you look at it from an angle | When you look at a monitor close to sideways it reverses colors, why does it do that? | Technology | explainlikeimfive | {
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"For older monitors, new technology has changed this, the basic idea is that you have three layers. At the back is the backlight, which is a plain uniform white light. In front of that you have the actual LCD, which is effectively a grid of little squares that can be electronically controlled to let more or less light pass through. Finally you have the colour filter, which makes the light from each little square either red, green or blue, in an alternating pattern. One pixel contains three of these, one for each colour. For older panels, the switching layer and colour filter layers were separated by a short distance. This means that if you don't look at them straight on, some of the light intended to go through one of the colours can be visible through the filter of its neighbour, and if you look from a very sharp angle, it is only visible through the neighbouring colour, hence the colour reversal. Modern LCD panels use a different construction that brings the colour filter and switching layers together, and OLED displays use an entirely different method that generates red, green or blue light directly rather than filtering white light."
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jm53nw | When tech support tells you to power something off and wait a number of seconds (i.e; 30 seconds) before turning it back on, what is the purpose of this delay? What could possibly be happening in this waiting period, considering the item is without power? | Technology | explainlikeimfive | {
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"30 seconds is usually excessive. However, many electronic devices rely on something called a capacitor which stores electricity, and keeping the device powered off for a few seconds allows the capacitors to drain and ensures the device fully powers off. You’ll notice that sometimes when you unplug a device, the power light can stay on for a second or two. This is especially common with devices that have external AC adapters, where the adapter itself can still be discharging power for a few seconds. Other times, it’s purely a stall tactic while the tech support representative does additional research.",
"A lot of people have mentioned capacitors which is correct, but also some network connections take some seconds to timeout. So like when you restart your modem it's good to wait 30 seconds or so to make sure you have a fresh connection when turning it back on.",
"Capacitors hold a charge even after the power is off. They will usually have a bleed off resistor that drains that charge away. That's what you are waiting for. You can do a little experiment to see it in action. Plug in your phone charger in to a power socket, but don't plug it in to your phone. Now unplug the charger and then quickly plug the chord into your phone. You should see that your phone will charge for a brief second. That is from the capacitor. If you wait longer to plug your phone in nothing happens because the capacitor has been drained.",
"The item being without power is exactly what IT/Tech Support wants. So, to preface anything, you have to know that machines, any machine, from your computer to your coffee brewer, from your cellphone to your TV... Doesn't know \"innately\" what each button does. There is a piece of \"firmware\" telling it what to do when pressing each button as needed. That piece of firmware is loaded onto a \"volatile memory\", that is to say, a memory that requires constant electricity to keep what is stored on it. You may have heard from a computer the word \"RAM\", which is one of the best example of that. Removing all electricity from the machine, will force that volatile memory to lose all its data, and have to reload the firmware as it was the last time it was working great. Doing that, if it succeed, it means that something went wrong while the machine was powered on, and the RAM itself got something wrong as it was moving data around, and it caused a situation where the firmware needed to be reloaded to worknproperly again... And if it fails, we know the issue is either hardware, or that the firmware that the machine boots was corrupted in some way. Usually, both of those requires in-deoths fixing.",
"It takes a little bit of time for power to fully drain out of the capacitors and other electrical components. The delay ensures it fully powers down.",
"Let's try ELI5 Your device has some things like tiny batteries (capacitors) that just lose charge over time, as well as parts that store information temporarily (memory). So the batteries are like a tiny bucket of water with a hole in it, so when you stop pouring water (electricity) in it, it slowly leaks out to empty. The memory is like lots of tiny buckets, with tiny holes, that have either clear or nothing in them. Generally your device \"knows things\" based on how these buckets being filled or not. So if you turn on your device before these buckets fully drain it might think it knows something still (rare but possible). So you let it all drain to fully reset everything."
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jm79jb | Why do noice cancelling headphones allow you to hear yourself but not other people? | Technology | explainlikeimfive | {
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"You hear others through the sound waves entering your ear from the outside. The noise cancellation can deal with that. Your own voice is made inside your own body, by the vibrations of your vocal chords. Those same vibrations can travel through your body and reach your ear from the inside. Noise cancellation cannot stop that."
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jmh8b3 | How did armies in the past make so many weapons(swords,spears...) with their primitive technology. | Technology | explainlikeimfive | {
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"Calling the technology of the past \"primitive\" is technically correct, but it paints an inaccurate picture of how adept people of the past were at doing things. Forging techniques have been under development for thousands of years, and while the industrial age certainly made metalworking far cheaper and more precise, lots of advancements were made in that time period before industry, enough to make really good metal weapons, swords for the wealthy, spear-heads, that used relatively low amounts of metal, and we're quite effective, and other things.",
"I'm no expert, but I can speculate. The weapons were simple to make, especially spears which are very common due to how easy they are to use. And I would guess that a spear tip doesn't take long to Smith due to how small and simple it is. In war time, I would assume that blacksmiths are working all the time to produce for the ear effort. Smiths producing spear tips, and I assume it isn't all that difficult to make the shaft. Having a ton of Smiths and a ton of people making the shafts ensures you have a steady supply. Swords have the same idea, blacksmiths working full time on them, but they're a little more complicated to make. Additionally, young boys would go to a battlefield after the battle was over and collected all the weapons and armor and anything else that's useful, so it would be hard to run out of arms and armor. That's all I got.",
"Brute manual labour really. Plus you have to remember that not every weapon is equal. Swords are a rich man's weapon for instance. They require a lot of metal and work to make. And a lot of training to use well. The same amount of metal could make a lot of spearheads or arrowheads. The most common weapon throughout history is the spear. It's simple to make. Simple to teach and very effective in large formations. In the early dark ages, peasants conscripted for war often made their own polearms by mounting the tools of their trade on top of a pole. Butcher's cleavers, farmer's implements. They'd just march off to war with a motley collection of homemade weaponry. But yeah, if you're looking to make a lot of weapons at once, it's basically just a ton of manual labour. And people planned for that. In medieval England, it was mandatory for men to practice the longbow at least once a week for instance. And it wasn't uncommon for people to make some extra coin during the winter making enormous numbers of arrows. We've found purchase orders for tens of thousands arrows. So to sum up your question. Half the answer is dumb hard work and lots of it. And the other half is that the fancy weapons were pretty rare. The majority of soldiers required smaller items like arrowheads and spearheads that could be produced much faster."
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jmkp7g | How do stealth boats/planes/submarines hide themselves from radar? | Technology | explainlikeimfive | {
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"Planes and boats have carefully designed angles to their surfaces, along with special materials, to reduce the reflection of radar waves. Planes also have things like internal missile storage to reduce the surfaces that radar can reflect off. Submarines are not detected by radar (at least underwater) but sonar. They use similar ideas to reduce reflection, but mainly rely on quiet propulsion systems and sound proofing the interior, to reduce their chances of being heard by hydrophone systems.",
"> How do stealth submarines hide themselves from radar? Can only talk about subs here. Submarine detection isn't done with RADAR. RADAR is RAdio Detection and Ranging, and radio waves don't travel well in water. Instead submarine detection tends to be done with SONAR (SOund NAvgation Ranging). There are two modes to SONAR - active and passive. Passive: Essentially the detecting ship/boat has very sensitive microphones which listen for noises in the ocean. They try to filter out natural sounds like fish/whales/ground movements. Anything mechanical sounding or rhythmic gets flagged up and reviewed. It's possible for the systems to identify specific types of ship/boat by the noises they make. As you're only listening, it's not possible to detect that someone is listening, but it's quite difficult to do this well. Active: The detecting ship/boat sends out a very powerful audio 'ping' which is reflected by anything nearby and those reflections are detected by the same equipment. The same as RADAR/LIDAR etc. The big disadvantage with this is that this immediately broadcasts the location of the sender to all boats/ships in the vicinity. Submarines are coated with special sound-absorbing tiles to try and reduce the amount of noise they broadcast and reflect, all mechanical equipment (such as propellors) is specially tuned to be as quiet as possible, and the crew are trained in how to manoeuvre the boat quietly and efficiently."
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jmlnrf | What is Raspberry Pi and why do people care about it? | Technology | explainlikeimfive | {
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"It's a small/portable computer board. If you hook it up to an external storage (HDD), mouse, keyboard, and a monitor, it basically becomes a cheap, portable computer (even more so than traditional laptops). It's famous because people who like to tinker with computers often use it for personal projects: creating a file server/backup for your personal stuff that you can access over the internet, creating a media center for your TV/computers, hooking it up to a camera and creating a monitoring system... Those are all things that can be done with a Raspberry Pi for a relatively low price and very good portability.",
"It's a small little computer. It's cheap to make and can therefore easily be bought for less privileged communities for leaners who never have access to proper computers. I have 2 Pis myself, connected to my 3d printers. It allows me to connect to them from my house and monitor/control the prints.",
"It's a small affordable bare bones computer that can do a myriad of things from simple alarms to fully developed arcade systems. It represents a new direction into automation in your own life. The fact that you can build these things for under 50 bucks in many cases makes the possibilities much greater than your standard build. It is also the size of your palm which makes it highly portable and can be setup to run in almost every situation.",
"Another nice thing with them is that because they're so cheap, you can have lots of them. Someone else mentioned having one for a 3D printer. That's a very common use. I have one of those as well. I have another one that does nothing but act as an adblocker for my entire network (and one doing the same thing at my work). If you want to try that, it's a pretty easy project. Look up how to make a Pi-Hole. In fact, if you're really interested in learning what a RPi is and how to use one, your best bet is going to be to buy one. They're not expensive. You can get a Pi3 for like $35. More if you get it with a case and some other accessories. Just make sure you have an SD card laying around or you buy one (or it comes with one). Also, if you don't have a keyboard/mouse/screen to connect to it, you can set it up 'headless', but it's extra work. It's not difficult, just more work since that vast majority of tutorials for setting them up don't include how to do a headless set up, and the tutorials that show you how to set up a headless RPi, assume you're familiar with setting them up to begin with. (IOW, trying to learn both at once makes for a steeper learning curve, but very possible, it's what I did)."
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jmlscc | Why does transistor size matter for PCs? | Technology | explainlikeimfive | {
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"The smaller they are the more we can fit on a chip. Also smaller transistors are faster because they need less charge to open them (wich also reduces power consumption). A very simple example to explain why more transistors are better: to build a circuit that adds binary numbers you can build one that adds them bit by bit and carries the overflow to the next circuit. So adding numbers of length N takes N timesteps. But you can also split it in 3 parts, where 1 calculates the first N/2 bits, and the other two calculate the second half assuming the First half has an overflow of 1 or 0 and then you select the correct result. In total you doubled the speed, at the cost of 50% more transistors."
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jmo6k5 | Big brands like Apple, Samsung, OnePlus and Google just so happened to all put a focus on budget friendly phones this year. How do tech companies know what products to produce/release every year in order to compete with other companies? | Technology | explainlikeimfive | {
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"As far as competition goes there are tech spies and people working on the inside everywhere. There’s too much at stake to not be spying on the competition.",
"Market research is a big part of it. These companies will gather a cross section of people together and ask them questions about their preference in relation to various products. They can then take the answers to those questions, and predict what type of product will be effective, and what will not. In addition to that, these big brands have been producing similar products for a very long time, it's probably easy for them to read trends based on what has worked in the past and what has not. And even further than that, the state of the world certainly helps determine what kind of product a company produces, especially an every day item like a cell phone. This year has been a financial struggle for a lot of people, and a lot of people who may have spent a lot of money on a phone last year will not be able to this year. The big brands want to make sure they have some sort of revenue at the end of the year, so they focus on making the product more accessible to a wider group of people: this year that wider group of people are clamoring for budget friendly options."
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jmqmrv | How is it possible that we don't have a system set up that allows voting electronically in 2020? | Technology | explainlikeimfive | {
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"Security. Such a online ballot system would be an extremely valuable target to anyone seeking to manipulate an election. Without some system to assign every eligible voter some form of unique online authentication that can't be easily stolen (which would be massively opposed for political reasons), it would be extremely difficult to reliably prove that each person who submitted a ballot is actually the person the ballot was intended to be sent for. Many states use electronic voting machines for convenience, but for example, in my state, a printed ballot is printed as a paper backup, and that paper record is scanned and stored securely as another backup. If the voting machine totals differ from the electronic ballot storage totals, the paper ballots can be manually counted.",
"With paper ballots there’s a hard copy backup if any funny business occurs. If ballots *only* exist in the digital ether, that’s a recipe for absolute disaster when the Chinese government wipes out California’s servers in a cyberattack.",
"No system is hack proof. Even the largest, best equipped and best staffed companies get hacked fairly regularly. Also, even creating such a system would cost more than decades of paper ballots and poll workers (who are generally volunteers)"
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jmrw0g | What exactly does a router do? | Technology | explainlikeimfive | {
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"A router does what it sounds like...it routes data to the appropriate part of a network. The internet backbone cables don't handle anywhere close to the total traffic on the internet, no physical cable can do that. Data only runs over those parts of the network necessary to communicate between any two computers. Routers are the \"gateways\" that figure out which data should go which way. You can't plug your LAN cable into your telephone outlet because those are different protocols (different agreements about what wire does what and how signals get transmitted). The thing that translates between protocols is a modem. With the right modem, you can plug your LAN cable into the modem and your modem into your telephone outlet. Just to confuse things, in a residential setting it's \\*really\\* common for the modem and router to be one piece of hardware, but it's doing two functions. The modem function translates protocols; the routing function determines what requests go out onto the internet and which stay on your home network. For example, you streaming from your PC to your TV has no need to leave your local network.",
"Do you mean an actual router, or a modem (or some combination modem/router which is pretty common these days)? In home networking a router typically connects *multiple* systems to a single internet connection. It *routes* packets from one device to another...in this case, from your computer to your modem, or from one computer on your network to another. The reason you can't plug your lan cable into a telephone outlet is because your computer can't translate a signal into something a device on the other end of that phone outlet can understand. This is where a modem comes into play. It takes the signal from your computer and turns it into something that can travel over the telephone outlet (or cable outlet if on cable internet). It also turns an incoming signal from that outlet back into something your computer can understand. Generally speaking it'll go something like this: transmission medium (phone/cable outlet) - > modem - > router - > computer Outbound is the same as above but in the opposite direction, and often the modem/router are combined into a single device for home use. In very simple terms, a router simply tells your data where to go, but by itself it can't translate your data from English (computer-compatible signals) to French (electrical signals) or back - that's what the modem does."
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jmtg4z | If I enter a password wrong thrice, the system locks me out. How are hackers able to attempt millions of combinations of passwords without the system locking them out? | Technology | explainlikeimfive | {
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"They typically aren't just entering passwords into the website like a normal user. Here's an example of a different way that they could be doing it. Good websites don't actually save a list with people's passwords written on them. That way, hackers can't just steal that list and know everyone's passwords. Instead, the website will run your password through a \"hash function\". A hash function is basically a thing that, if you put a word in it, will mix it up and garble it in such a way that it is impossible to undo. So, the website runs your password through the hash function and saves the resulting garbled version. When you enter your password into the website to log in later, the website takes what you entered, runs it through the hash function as well, and if the resulting garbled stuff matches the garbled password they had saved, then they know you must have entered the right password, or else the two garbled things would have been different. Websites do this because even if a hacker steals their files, all the hacker will have is a list of garbled passwords. The hacker can't ungarble the passwords to get the real passwords, so they are kinda stuck. However, they can use the garbled list to guess your password. If the hacker also knows what hash function the website is using, the hacker can run millions of password guesses through the hash function themselves, and then check to see if the resulting garbled guesses match any of the garbled passwords on the list. If they find a match, then they go to the website and actually enter it. The analogy would be, instead of trying a million keys on the lock to the building they are trying to break into, they steal a copy of the lock, take it home, and try a million keys on the copy at home where nobody will see them. Once they find the right key, they bring it to the building and get in on the first try.",
"The hacker may have found some exploit that allows them to run code on the web server, or otherwise have gained access to the database where hashed passwords are stored. The restriction you mentioned is implemented in the website itself, not by the database holding hashed passwords.",
"On systems with lockouts, hackers are not attempting random passwords in to try and access accounts. The main way they would get in is with a leaked password database that contains usernames, email addresses, and passwords that they can crack at their own leisure. They then try those passwords in other sites and hope that the user reused the password.",
"Let's say you have an iPhone you want to hack into. You can keep trying passwords, but the phone will lock you out so you can't try anymore. What you CAN do is download the phone onto your computer and have your computer try millions of passwords trying to get into the phone. This bypasses the lockout."
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jmwg4j | Computers. How do they... work?? | Technology | explainlikeimfive | {
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"Your computer is millions and millions of tiny switches. The configurations of those switches impact other switches. If you could control your computer at the most basic level, you would tell it which switches to turn on and off, and it would give you results. The \"lowest level\" code is called machine code - and it directly instructs the CPU to do extremely specific things, at the level of individual switches. But it's pretty rare to write programs in machine code, mostly because that would be incredibly tedious. So if we want to write programs, and we don't want to use machine code, we need a \"middle man.\" And that middle man is called a compiler (or an interpreter, depending on the language.) We write our instructions to the compiler in a language that we understand, like C++ or Python or whatever, and the compiler translates those instructions into machine code.",
"I can give you a very simple example on how computers do something like math. In binary, 1+1 = 10 since it's base two. When the ones place reaches 2, it overflows to the twos place just like when you add 1+9 in base ten it overflows to the tens place to equal 10. So how do we add two base two numbers in binary using circuits? Well we use [logic gates]( URL_0 ). Pass two electrical signals into a logic gate and it will give you a certain electrical signal back. For instance, an 'and' gate returns 1 (true) only if both signals passed to it are 1. (In computer speak, binary 1 and true mean the same thing, while 0 and false are also interchangeable.) Putting variables X and Y into an and gate is like saying \"Is X and Y true?\" If either X or Y are false, then the statement isn't true and so it'll return 0 (false). \"Or\" gates will return true if either value passed to it are true, and only return false if both are false. It's like asking \"Is X or Y true?\" I'll need to tell you about one more gate before I can get to solving math though. And that's an \"exclusive or\" gate. It only returns true if X or Y are true, but will return false if both are true. So (1,1) or (0,0) return 0, but (0,1) or (1,0) will return 1. So think back to adding in base two and you may notice something, if I add 1+1 in base two I get 10. 0 in the ones place and 1 in the twos place. If I add 1+0 or 0+1 in base two I get 01. 1 in the ones place and 0 in the twos place. Plug the numbers into an exclusive or gate and you'll get the same results for the ones place. Plug in the numbers into an and gate and you'll get the same results for the twos place. This is just a very simple example of doing very simple math, but you can build off addition to do multiplication. You can even build off of addition to do subtraction. With creative use of logic gates, you can add even bigger numbers more efficiently. When you drill down to the very core of what computers do to make decisions or get results, it comes down to bits being passed through logic gates. That's the magic of it."
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jmxzb4 | How did we come up with Bread? | Technology | explainlikeimfive | {
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"Both yeast and salt is optional. Bread can be as simple as mixing flour and water. This is very similar to how you make porridge or soup. It all just depends on how much water you use. And it does not take much of a genius to figure out that you can make certain plants eatable by crushing them and boiling them in water. As for the yeast it exists in the wild and will coat the grains in the fields naturally. Even to this day wild yeast can be found in the flour you buy at the shop (as long as it is not bleached). If you do not wash your cookware then the yeast might grow in the old dough and infect any food you are preparing. In fact this is the principle behind sourdough and is not far from how commercial yeast production happens. So it is easy to stumble upon the discovery of yeast in bread to make it more fluffy. If you do the same with porridge or soup you might end up with something similar to beer.",
"Eating grains most likely came about from desperation and curiosity. Grains, however, are quite hard, so they are easier to eat if they've been soaked, like porridge or oats. Grinding the grains also makes it easier to eat, as the hard shell is broken down and the nutritious insides are easy to access. Combine these together, and you have a thick porridge (probably not the right proportions to make a dough). However, if you make too much of this porridge and leave it out overnight, the yeast in the air will start to colonize it and grow in it. The porridge will start bubbling, because the yeast inside is digesting the ground grain (flour) and making some carbon dioxide. One person who's a bit curious cooks it and finds that it tastes better. If the porridge was left out too long, it may have dried up some, which brings it closer to bread. Then, the porridge undergoes some magic and puffs up when cooked! The texture is also different, as the water is replaced by some air. This would be the first bread; sourdough fermentation of ground wild grain in water."
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jn0oul | Why do power banks charge phones instead of sucking power off of phones? | Technology | explainlikeimfive | {
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"In addition to what everyone else said...diodes. Diodes only permit electricity to flow in one direction.",
"It outputs at a higher voltage. Let's pretend it's a few years ago for simplicity: The bank puts out 5v, just like a USB charger. The phone runs at 3.7v. 5 > 3.7 so that higher potential wins and the bank \"pushes\" current into the phone's battery. Current charging protocols for phones futz around with the traditional usb 5v/3.7 voltages so banks and charges may be putting out 9v or 12v, but the concept remains the same."
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jn6w1m | How does radio work, what's the difference between AM/FM, and how can one block/interfere radio trasmissions | Technology | explainlikeimfive | {
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"AM -- > amplitude modulation. The information (music, speeches) are modulating the amplitude for a defined carrier frequency. The receiver needs to tune the oscillator that is matching the carrier frequency. This can be done with a capacitor. The low quality of AM comes from the modulation. Any disturbance of the amplitude will be hearable. Advantage is longer range and you may hear some noise even on very weak signals. FM -- > frequency modulation. The signal (music, speech) will shift the carrier frequency. To provide two channels for stereo, the main frequency transmits the sum of both channels. At an offset to the carrier, the difference between the two channels will be transmitted. The modulation allows an higher quality of the transmitted signal. However, since there is no way to distinguish between the signal and the disturbance, it can be also jammed by other signals. E.g. usually the carrier frequencies between 87 MHz and 107,5 MHz as defined range, allows carrier on each 50 kHz step. That is too close and so in a specific area, the carries are more far away. One radio broadcast is sending at 89,2 MHz and the next is on 90,1 MHz. The range is not so far and as said, the stereo transmission will be cut firs, since the pilot signal would be too weak. But you could still hear the Mono (=Sum of both). Again, there is no way to distinguish the signal from disturbances and so the signal is also vulnerable to it. How you can block/interfere transmission: - send a broadcast on the frequency and apply noise. The receiver will mix it up and the signal is jammed.",
"A radio works by sending or receiving an electromagnetic wave. The transmitter makes the wave and sends this field out at a particular wavelength, and your receiver - when tuned to that wavelength - picks it up and changes it to sound. Unshielded electronics can also send out signals all over different wavelengths, which is why things like microwave cookers (and for me - a machine used to stop bleeding during surgery) can interfere with the reception quality. AM stands for Amplitude Modulation. Basically the information in the signal is sent by varying the strength of the signal. Think a bit like normal data where everything is just 1s and 0s with a low strength being a 0, and a strong signal being a 1. It's far more complex than that - but thats the idea! FM is Frequency Modulation. The information is sent by the number of waves per second, rather than by their strength. AM is a lower quality, and is more affected by other sources or electromagnetic waves, but carries much much further. FM is high quality, but doesn't travel as far, and is affected by physical barriers such as buildings or hills. As to jamming - generally you need to transmit another signal on the same or close wavelength. If your signal is more powerful from the point of view of the receiver then it will add so much \"noise\" (randomness) to the original that the receiver cannot distinguish the bits of information for AM, and for FM it just completely overwrites the information. Signal strength is *inversely proportional to the square of the distance* (if you double the distance the strength is divided by 4, triple the distance and it's now only one ninth as strong, etc.) so a fairly weak signal can override a strong transmitter as long as it is much closer to the receiver. Anything that uses or generates electricity can be a source of interference (which is the same as \"blocking\" on a lower scale) which is why you cannot use your phone on a plane! (Which has been shown to have no affect on the modern electronics of today's aircraft... but it could in theory anyway!) It's also why you can't use your phone at a petrol station - it's not a fire risk (which is what they say) but because, in theory anyway, it might affect the electronics in the pump and you get free gas! On a slightly different note - once the aviation industry gets an idea it never lets go. For example, sphygmomanometers (blood pressure machines) are banned on aircraft as the old one's contain Mercury, which if it leaks will \"dissolve\" the aluminium of the aircraft. Airport security were refusing to let me take my electric one (without any Mercury!) on a plane where I was going on a medical mission to a disaster zone... because it was banned. And they had no idea of why. Not sure that made sense anymore! Ask if not!"
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jn7ihl | Why can't bad guys, rogue nations, hackers commandeer Voyager 2, et al? | I haven't found a comprehensive look at what sorts of layers of security go into safeguarding these vessels. I read an article of some antennas being used to communicate with Voyager 2 while her usual terrestrial antenna is repaired. Ok, but what's to stop anyone else from communicating in the interim? Or ever? Is it locked frequencies? Very specific API requiring perfect names, function calls, encryption keys? What exactly do space-level security and encryption mean? How does this age? & #x200B; Thanks!! | Technology | explainlikeimfive | {
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"To communicate with Voyager, we have to use very big radios. These radios are run by the NASA Deep Space Network. They are in Australia, Spain, and the USA, because then, at least one is on the side of the Earth that can see the part of the sky you're talking to. The telescopes they have to use are HUGE. The Madrid station has several that are 34 meters across, and the main one is a big bowl 70 meters across! That's as big as a jumbo jet! Nobody else can communicate with Voyager because radios that large are very expensive, and they're the only way we can.",
"Space is big. Really big. You just won't believe how vastly hugely mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist, but that's just peanuts to space. Voyager 1 is about 22.5 *billion* km out. At that distance the 3.7 high gain antenna is a target about .339 nano-arcseconds \"big\". That's half a hairs width on the moon. So \"security feature\" 1 is being very hard to actually get to. Next is power. Sure, you could just spam random binary it out there, but that won't get you far. Voyager 1 transmits at a power of ~23 Watts, and for 2014 – when at a distance of \"only\" 15 billion km – [it was calculated]( URL_0 ) that the arriving signal had a strength of about an *attowatt* (10^(-18) W) left. That's not something you pick up with a simple [Yagi-Uda]( URL_1 ), for that you need a pretty big dish with enough power. So \"security feature\" 2 is specialized hardware requirements Level 1 (Level 2 being the computers from the 70s actually able to speak the special dialect used). Then there's \"security feature\" 3, brute force protection by the simple fact that the comms delay is currently 1.75 days & growing. And last but not least is a simple cost-benefit analysis: all that effort to get access to a scientific instrument, similar to a microscope, that's on a no-return path, has no propulsion, and can barely keep its instruments heated & powered? Nah, pass.",
"Part of its security is that you don’t know what security protocol it uses :) you also can’t really brute force or throw everything at it to see what sticks, since there’s a high risk it just stops responding and you just turned a communicating brick in space into a dead brick in space. The main thing is, it requires a tremendous amount of resources and global coordination to get a stable signal to the voyager. There’s also not much to be gained by “taking control” of it, apart from maybe some press coverage. Finally, at the transmit powers you need, your operation will be found out really soon, so you only have a short window to even try.",
"Well, I guess the first obvious question that occurs to me is: why would a governmental organisation bother? What benefit does hacking a probe millions of miles from Earth get them? As for amateur hackers, the sheer size of antenna and transmission power required to communicate with something so distant makes it completely impractical for them to have a go, no matter how much of a \"feather in their cap\" it would be."
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jn84wy | where/how is the data on the internet stored? | all the youtube videos, blogs, photos etc. | Technology | explainlikeimfive | {
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"Servers with a ton of hard drives inside warehouses called data centers, it’s really not much different from how data is stored in your hard drive, but multiplied thousands of times.",
"On servers. A server can be your own computer, or it can be a massive warehouse kept very cold and filled with hundreds of servers stacked one atop the other in towers. Either way it's a computer whose primary function is to store and allow access to whatever information for websites. Some companies build and run their own servers while others rent server space from a server farm (the giant warehouses). These huge server warehouses are found all over the world and are the infrastructure of the physical internet."
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jn8thp | What exactly is the difference between UHD(Ultra-high-definition) and 4K? | Technology | explainlikeimfive | {
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"**UHD** 3840 x 2160, always. **4K** There are two variations, and the definition is usually dependent on what industry we’re talking about. In the film/TV/video industry it typically refers to *4K DCI*, which is slightly wider than UHD at a resolution of 4096 x 2160. In the gaming world, 4K is typically used more as a marketing term in place of UHD. Where it gets confusing are when certain videos that are listed as 4K -don’t- use 4K DCI, but instead UHD, as people from that world usually expect 4K DCI and those extra 256 pixels in the width. Resolution mismatch can lead to issues with the recording and broadcasting of video, hence why the difference matters in film/TV/video production, but not really in everyday gaming. Edit: No matter how hard I try, I can’t spell while on my phone.",
"UHD is a resolution of 3840x2160. 4K was a term originally used in cinema to refer to an image with 4,096 lines of resolution, so slightly higher than UHD, but in current general usage the terms are interchangeable."
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jnawzq | What's the difference between a Microcontroller and a Microprocessor? | Technology | explainlikeimfive | {
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"Microcontrollers are normally fully integrated systems on a single chip designed for embedded systems. They'll have onboard memory, serial lines, etc. - everything you need to automate a small device in a low power system. Microprocessors are generally just the processor and are intended to be connected to external peripherals.",
"A microprocessor is just a processor (the micro is kinda redundant nowardays, nobody is making macroprocessors). It can do math and logic and can talk to memory but not much more, it needs that memory and any peripheral controllers you want to use wired to it externally to do something. If you look at lets say a C64 board it has a 6510 microprocessor and a whole lot of other chips that are necessary for it to work. Same on a modern PC, you have the CPU and then RAM, Chipset, Usb controllers etc. that it needs to work, the CPU alone wont do anything. On a microcontroller you have a processor together with memory and some types of peripheral controllers built in. This makes it much easier to work with, since you may only need the microcontroller and a powersource to get it running, with the drawback beeing less flexibility, since you can't easily add more memory or peripheral controllers to it.",
"Both of those terms may refer to the same thing, depending on who you ask the definition might be blurred. Some people might argue that a Microcontroller already has a program installed on it and then only expects input while a Microprocessor requires a program to be loaded into it do to anything."
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jnb29f | Why websites want me to install their app even if it's same as the website? | Technology | explainlikeimfive | {
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"Sometimes they can offer a more optimized experience on an app than they can in the browser, such as by allowing phone calls and notifications directly to your phone vs email. It's also easier to collect your personal data and target ads to you with an installed app.",
"The theory : apps can do more than websites : they can control or take advantage of your hardware, for example filters on your camera, or the accelerometer. In practice : apps give the editors the ability to track you better and to send you notifications you drag you back in.",
"A dedicated app also works as a \"foot between the door\". If you have the app installed, you are more likely to interact with it.",
"Because you have to agree to all the conditions to installing the app, which means (usually/potentially) your location, camera, microphone, search history, can all be used by said app. (You haven't had video games pair you with teammates/enemies that have names of topics you said in vicinity of your phone, but never on a call or never searched it on your phone? Almost like companies build a digital avatar of your personality and things/people you are in contact with, and they can exchange this information between companies.)",
"Track your usage and sell more of your data to other parties, especially if both are free to use.",
"Not sure why the obvious \"data tracking\" answer isn't near the top. Apps give GPS coordinate data, Websites get rough inaccurate IP based locations. Apps can use the devices microphone and camera, a pure browser based website can not. Websites can find out what other websites you visited, apps know what other apps you have installed and how much you use them. Websites will require you login to profile all this data, apps profile you automatically through your phones account.",
"It may look the same, but an app puts 90+% of the static content, code/scripts and other resources needed to create the user experience on your device ahead of time. When you use the web, all of that content needs to be served up by a web server and sent through the owner's Internet connection. Web servers and network capacity cost money. Putting it all on your device cuts down on server and network utilization, saving money. If the site/app has millions of users, we're talking millions of dollars saved every year.",
"Sometimes an app can actually give you a more rich experience. For instance, think if your cell phone providers support portal. It could use information from your phone and its network to authenticate instead of having to go through a login process. Apps like Amazon can use it to send you push notifications for delivery notifications. Other times, it is done because they want to create a captive experience. If you open a web browser, there's not as much preventing you from going to a competitor. If you open an app, you're not going to go to a competitor instead. And finally, the most likely reason for a random website to want you to use their app that wraps the website is because some exec-level idiot decided \"We need an app\".",
"Websites make money through ad-sales. There are two main types of web-based ads: ad-network, and direct-sale. In an ad-network, the website makes money by showing ads and getting people to click on those ads. In this model, advertisers buy impressions through the network and bid/compete with eachother to get the right types of eyeballs on their ads. The website and the ad network both get a share of this In direct-sales, the website negotiates directly with the brand or an agency representing the brand. In the process of negotiation, one of the (many) factors that is used to sell holistic ad-products is statistics on their viewership, which includes app usage numbers. The more app downloads, the better the sales story for the salesmen who are responsible for convincing brands and agencies that buying ad products from their publication is a good idea. In short: app usage is a helpful metric for sales."
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jne50a | How do banks know that it’s not you using your card when they send out those fraud alert messages? | So I just woke up this morning, made my coffee and was scrolling through Reddit.. And I got a Fraud Alert text from Chase telling me they declined a purchase of $153.60. I buy stuff *all* of the time with my chase debit card.. online, in store, sometimes run it as credit.. and I never get those fraud alert messages. But, the first time that someone somehow stole my card numbers and tried to make a purchase, they declined it and flagged it as fraud. And thank god they did.. but how did they know it wasn’t me? | Technology | explainlikeimfive | {
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"The credit card company knows a good deal about you. They know where you live, where you usually shop, what you usually buy, etc. If they detect a purchase that deviates from your patterns, they will flag it as potential fraud. So, if you normally buy food, gas, groceries, etc. on your card in one particular part of one city, then someone buying electronics in a different city is going to raise flags.",
"Usually those kinds of fraud detection occur by looking for simple patterns. For example suppose you live in New York City and regularly make purchases there or to be delivered there. One day they see you make your normal purchase at the Starbucks down the street, then 20 minutes later you supposedly purchase a bunch of cigars in Cairo, Egypt. Did you learn to teleport? Even if you had planned to travel there, which you haven't before, it is physically impractical that you traversed that distance in that time. Or suppose there is an online cigar seller who suddenly gets 100 orders from various credit cards. The credit processing company already knows that some of those cards have been stolen so they suspect the entire batch is fraudulent.",
"It could be the location. If you use your card in Alabama all the time and then someone used it in Scotland somewhere they will flag it because it's not likely that you went to Scotland.",
"Their exact methods are propriatary and secret. This is both to get a competative advantage over other banks but foremost so that people who steal credit card information can not use this information to avoid getting detected. What is known is that they look at a vast number of different parameters. They do have your entire transaction history and is able to build a very accurate profile on you. For example we do know that they look at flight times and gas station purchases to try to find out where you are or at least where you could possibly be. If the physical credit card is used outside of this area they mark it as potential fraud. To the anoyance of people speeding. They also collect data on what you typically buy online as well as what typical frauds will start buying and mark transactions as suspect. And although it is not confirmed it is suspected that banks buy data from Facebook, Twitter, Amazon, Google, etc. and other websites you visit or have embeded advertisement or share buttons on websites in order to track your every movement online and therefore find out when you visit a webstore, how long you spend in the store, what you are looking at, etc. and only confirm the payment once this information is established.",
"I use my credit card to make big purchases here and there. I use it for cashback. But I never got flagged. European trip, furniture for the house, business costs, etc. No issues. Then last month I went into sally's, a beauty supply store, to buy some fancier hair care stuff. I spent $10. My bank sent out fraud alerts and called me. I guess they know my patterns. So $10 at a beauty store was enough to raise eyebrows.",
"For a time I worked at American Express and handled quite a few fraud calls (card members with alerts and calling about fraud we missed). A whole lot of AI/machine learning. Basically it looks for patterns about you. Also, as others have said, card companies know a boat load about you and your shopping habits. That said, they still miss \"you\" buying a plane ticket for someone you've never met from Kenya to South Africa while you're still in the US or $12k in chocolates and flowers in Paris while you're still at home in NYC (both real calls I've had). Nothing is perfect but, card companies are liable for fraudulent charges so they've got some incentive to cut down on it.",
"They look for all sorts of things... was it used in a geographic location you aren't in, ie. you used your card where you live and then an hour later it was used halfway across the country? Was it used at a store you never shop at, ie. you always grocery shop at Kroger and it was used at Publix? Maybe the person committing fraud used multiple fraudulent cards at the same store and that triggered a review of transactions -- I once had 2 different legit credit cards declined trying to buy gas once at a gas station in a kind of sketchy place but still in my metro area, when I called about it I was told it was a high fraud location I hadn't transacted at before."
],
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jnf27x | why do new British reality TV shows look like they're filmed in 2002 | Technology | explainlikeimfive | {
"a_id": [
"gb100nt"
],
"text": [
"If it was filmed in 2019, it was the American show: URL_0 Ramsey was also involved in the original British show, but that was back in 2004: URL_1"
],
"score": [
13
],
"text_urls": [
[
"https://en.wikipedia.org/wiki/Hell%27s_Kitchen_(American_TV_series)",
"https://en.wikipedia.org/wiki/Hell%27s_Kitchen_(British_TV_series)"
]
]
} | [
"url"
]
| [
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]
|
|
jnfa27 | How are thatched roofs waterproof? | I can see how they would keep heads dry at first, but all that water must soak into it and drop through eventually, right? | Technology | explainlikeimfive | {
"a_id": [
"gb109zd",
"gb0zjwc",
"gb0zyln",
"gb12gaw",
"gb1eshf"
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"text": [
"> all that water must soak into it and drop through eventually, right? *Eventually* can take a long time. You just have to lay the thatch right, and thick enough, and it's longer than any rainstorm.",
"They are very, *very* thick and built in a way that all the thatch points in the right direction to direct water off the roof.",
"If you take a piece of thick grass and put it under the faucet at an angle with the water on just a bit, some of the water will stick to the grass as it's flowing down because of surface tension. Thatched roofs use this principle with many layers of grass to move the water to the outside of the building by the time it as made its way through the layers.",
"Thatched roofs are usually installed with a significant. Slope to minimize water infiltration.",
"If it has a steep enough angle, the water just runs down to the eave. If you pour out a full glass of water very slowly, some of the water will \"wrap around\" the edge and run down the side."
],
"score": [
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11,
9,
3,
3
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| [
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|
jng8jg | How do search engines like Ecosia work? | Technology | explainlikeimfive | {
"a_id": [
"gb1akji"
],
"text": [
"Ecosia shows ads to its users. It uses some of the profits from those ads to fund tree planting programmes."
],
"score": [
8
],
"text_urls": [
[]
]
} | [
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| [
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|
|
jngela | pgp, keypairs and the likes. | Can someone explain tthese things to me? they don't make a lot of sense. I am also puzzled by plan 9's facotum/secstore, how do those work? | Technology | explainlikeimfive | {
"a_id": [
"gb1u5xc"
],
"text": [
"Imagine you want to send a secret message to me. You could write it in code, but the problem is you first have to tell me how the secret code works, which isn't easy to do because we don't have a way to send secret messages yet... So, what I can do instead is I can send you an open, unlocked safe. You receive the safe, and then put your message inside and lock it. You don't know the combination to the safe, so you can't get your own message back out, nobody can. You then mail the safe with the message inside, and I use my secret combination to unlock and open it. That way, you can send me a secret message without having to first send a secret code. Of course, mailing safes back and forth is difficult and expensive, so it would be easier if I just put a secure dropbox on the outside of my house. Anybody can slide a message in through the slot, but only I who knows the secret code can get those messages out to read them. Anybody who knows my address can send me secret mail, and my address doesn't have to be secret information, that's publicly available. The only thing I need to keep secret is the code to the dropbox. This is how PGP and other public-key encryption schemes work. Your public key and private key are mathematically linked so that your public key only \"locks\" secrets, while the private key only \"unlocks\" them. That way, its safe to share the public key around to everybody so they can all send you secret messages, but you keep your private key secure and secret because only that allows you to read those secret messages. This of course means that you need to know the public key of anybody you want to send secret messages to."
],
"score": [
3
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| [
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jnkloz | When the “restart” option is pressed on a console, how does it know to turn itself back on? | Technology | explainlikeimfive | {
"a_id": [
"gb1yrcg",
"gb1yw98"
],
"text": [
"Think of it more like an interrupt of the power. For example, you turn a light on in your house and it says on until you turn the switch off. Now add a button to the circuit between the switch and the light bulb. When you push the button the light turns off and when you release the button it turns back on because a spring pushed the button back out so the power can flow again.",
"It may vary from device to device, but generally speaking, powering something on and off and using a \"reset\" button to instruct the device to turn off and then automatically turn back on are completely separate functions and don't use the same mechanism. For many devices, the power button is closing a contact that provides electricity to a circuit that begins the process of turning something on. It's like turning a light switch on (in fact, it's almost exactly like that). A reset button can be a software function or control a contact the way a power button does. If it's a software controlled shut down and restart, then the power contact never opens (the light switch is on the whole time, but a computer decides to close down certain tasks and reinitialize). If it's a contact controlled reset button, then pressing the button turns the power off, but when you let go of the reset button you're restoring power. That is, pressing the reset button is a bit like turning the light switch off, but when you let go of the reset switch you're turning the light switch back on. In the console itself, you're actually flipping a different switch off and when you let go, it turns back on. For the console to work, both the reset and power switches have to be on, so the reset switch powers off the console just like the power button, but it turns back on as soon as you let go."
],
"score": [
10,
5
],
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| [
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jnnbyx | How is closed captioning (subtitles) produced accurately and quickly for live events? Is it hand typed or computer generated? | Technology | explainlikeimfive | {
"a_id": [
"gb2fso0",
"gb2fzll"
],
"text": [
"It depends. It used to be done by a skilled stenographer to be done as fast as possible with as few omissions as possible. Nowadays it is usually done with voice recognition.",
"It’s still done quite often with a live person typing away. But AI has started to gain a ton of steam in this. My company will use either with the live person being more expense, but also more accurate...for now. It’s literally just someone typing into a program that is layered over the program in the video switcher and/or processing."
],
"score": [
5,
5
],
"text_urls": [
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} | [
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| [
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|
|
jnoo9b | Why is volume rarely 0-10 on most electronics? | For example, my truck's volume goes from 0 to 55 but my PC counts from 0 to 100, but in increments of two. Why is this? | Technology | explainlikeimfive | {
"a_id": [
"gb2q6u9"
],
"text": [
"The greater the range the more precise you can be with the volume. If your volume counter goes from 0-10, 6 might be too loud and 5 might be just a little too quiet. If your volume counter goes from 0-100, 60 might be too loud and 50 night be too soft, but now you have 10 increments in between to fine tune the volume level."
],
"score": [
5
],
"text_urls": [
[]
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} | [
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]
| [
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|
jnp1rk | How does vinyl and CD works? | Technology | explainlikeimfive | {
"a_id": [
"gb2sdem"
],
"text": [
"Vinyl is a disc with one big spiral groove running from the outside to the inside. The groove is rough, with various jaggedness in it representing the sound of the music. You put a needle on it, and the movement of the needle within the groove is translated to sound. A CD also has a groove. But instead of jaggedness, it has a series of microscopic pits that represent ones and zeroes, which represent the digitally-encoded music. A laser reads these based on the differing reflectivity of the pits, and translates that back into digital music."
],
"score": [
9
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| [
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|
jnr424 | Why is the sound quality of a phone call via cellular so different from the sound quality of a voice chat via data (I.e. discord) on the same device? | I’ve noticed as the internet has grown that voice calls/chats using wifi or 4/5G have significantly better sound quality than a regular phone call, when using the same device and the same speaker. I know that they are using two different methods of data transmission but I have no idea how they work and why they transmit data differently. | Technology | explainlikeimfive | {
"a_id": [
"gb37slm"
],
"text": [
"Tl;dr: because the bandwidth and compression techniques used by the call are different. Traditional analog cellphone calls were *extremely* low bandwidth. As a result, calls on traditional cell networks (in the 80s and early 90s) only transmitted a fraction of the sound frequencies and compressed them very heavily. They made huge leap forward in quality when we moved from analog to CDMA in the 90s. More bandwidth meant more frequencies and less compression, although moving from analog to digital initially meant more dropped calls moving between towers. After CDMA came 3G, a data transmission method either piggybacking on CDMA or using the updated GSM format. GSM sounded better, but both still used packet compression phone transmissions that were still pretty low bandwidth. Neither were really suitable for transmitting phone calls using internet protocol (IP). The current generation of cell phone connections, 4G LTE, used CDMA audio for phone calls at first (and sometimes still does depending on your carrier and local tower capabilities) but once smart phones came out with VoLTE (voice over LTE), the bandwidth was greatly increased. Most phones call this \"HD Calling,\" but basically it routes your call over your LTE data connection instead of a traditional cellular connection, allowing for wayyy higher compression bitrates and more total audio frequencies. A VoLTE phone call isn't really traveling over the cell network, it's travelling over the internet. VoIP services like Discord never had this limitation. Even compared to LTE, VoIP calls have virtually limitless bandwidth, limited only by your internet connection. More bandwidth = more audio frequencies and less compression = better sound quality. Apparently, VoIP on 5G means cell calls should sound just like Discord. Here's to hoping that happens in real life and not just in their ads."
],
"score": [
9
],
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| [
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|
jnv2cb | why older cars need long extendable antennas for radio reception, while modern cars often only have little stumps on the top but still good reception | title | Technology | explainlikeimfive | {
"a_id": [
"gb3vk9d",
"gb3vg02",
"gb3y414"
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"text": [
"Sorry for my English. I ll try to be as short as possibile since it's in this subreddit. I think you are referring to fm am frequency, The answer is, it's a compromise for aethetic and more import cause GPS satellite antenna need to be protected. So ideally the antenna must be the same of the wavelenght but since you can't have 3 meter antenna even the 1/10 fraction can work. And now you also need antenna for GPS plus sometimes more satellite type. So we can do 2 things. We can use the back window of the car and hide a longer antenna around the borders that actually work better and stick the GPS in the little fin on top, or we can stick even the fm antenna inside the fin, bend it a lot and stick a rear inductant coil to try to gain more power, and be almost as good. In most case both solution are good enough. But again ideally even today, if you want to receive fm and am, best solution would be an antenna around 3 meters or ten foot on top of your car. Hope I was clear enough. Bye",
"Those stumpy antennas are often called Shark Fins, and they can also do satellite radio, cellular data, and GPS. For regular AM/FM radio, that antenna can be hidden elsewhere, such as embedded into a window. On my car, it’s located in the right rear side mini window. Advancements in technology have packed a lot more function into a much stumpier antenna. \\--- **EDIT** Adding a Google link to show what they look like inside .... [HERE]( URL_0 )",
"Essentially, it's because the AM/FM radio antenna is hidden - much like the WiFi antenna on your phone or laptop. In a laptop, the WiFi antenna runs [ around the perimeter of the screen]( URL_2 ). This gives it a decent antenna size while remaining completely hidden. Same for your phone, if you look at pictures of old phones they all have [huge aerials]( URL_0 ). More modern phones still have an antenna, it's just [hidden inside]( URL_1 ). In a car, the antenna might run around the windscreen or along the roof. The little stump on some cars doesn't usually hold an AM/FM antenna, it'll be for onboard GPS, satellite, or the DAB radio."
],
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"https://www.google.com/search?q=inside+a+shark+fin+antenna&newwindow=1&rlz=1C1GGGE___US535US535&source=lnms&tbm=isch&sa=X&ved=2ahUKEwia7Yj8wunsAhUCUt8KHRMhA9oQ_AUoAXoECAcQAw&biw=1097&bih=575&dpr=1.75"
],
[
"https://images.techhive.com/images/article/2015/11/old_nokia_phones-100625503-large.jpg",
"https://www.scionlife.com/forums/attachments/tc-tech-diy-1818/102337d1501486427-shaved-relocate-hidden-antenna-dsc02184.jpg",
"https://i.stack.imgur.com/yFAUo.jpg"
]
]
} | [
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| [
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|
jnvrk7 | How do people upscale old videos to almost crisp 4K? Old movies and music videos. | Technology | explainlikeimfive | {
"a_id": [
"gb3zzi5",
"gb3zgbu"
],
"text": [
"Film doesn't really have a resolution, it's just some chemicals spread on some paper or celluloid, the chemicals will change color right down to the molecule by molecule level. If you zoom in too much eventually the structure of the film or the quality of your lens means you can't zoom in anymore, but you basically have 'infinite' resolution on film, instead of a grid of a certain number of pixels. Like every single molecule of the film coating can change color in light.",
"The \"resolution\" of the 35mm films that were used since the 1930s is higher than 4K digital video. Lots of old TV, music videos etc was shot on film because the picture quality was better than the video cameras of the day. It is stuff shoot on videotape, lower-cost 16mm film or early lower resolution digital cameras that are hard to scale up. So a movie shoot in 2000 with a digital camera had worse resolution than a movie shot on film from the 1930s"
],
"score": [
4,
4
],
"text_urls": [
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]
} | [
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| [
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|
|
jnwd2e | if we can squeeze plenty of high tech pieces into a laptop then why desktops are still bulky ? | Technology | explainlikeimfive | {
"a_id": [
"gb4212a",
"gb42g3c",
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],
"text": [
"One huge aspect: increasing the clock speed of a processor (keeping everything else largely the same) increases power consumption and heat output dramatically. Space and power consumption aren't critical for many situations a desktop might be used, but the additional performance from a faster processor is desirable. In a laptop, the opposite is true: power consumption and heat output are very important details to minimize.",
"Think of it like a person can ride a motorcycle, but most choose to use a much larger car. The extra space opens up a lot of options.",
"Desktops are more modular. They have more internal space for extra graphic cards, hard drives and fans. Also desktops often still have disk drives. There are also smaller desktops.",
"Laptops make compromises. Processors that can't be running as fast as they could because there is not enough cooling, and often even so they still struggle with overheating. 95°C is not an unusual temperature for a laptop doing some work. My desktop PC doesn't exceed 75°C when going full tilt -and overclocked- rendering a video for a day and it is about as loud as whispering. Why? Because I can fit a 12cmx12cm tower cooler with two large, slow fans, while a laptop has to make do with a thumb-thick radiator and tiny fans that run at thousands of RPM. Same with expansion. I have 3 3.5\" hard drives and two SSDs in my PC - with still room to spare for one or two more. I have a full size graphics card that has its own cooler instead of mooching off of the already struggling CPU cooler. If I wanted, I could plug in a whole other video card to use for mathemathical computation, or a 10gigabit network card or a couple more SSDs. Can a laptop do that?"
],
"score": [
16,
10,
6,
3
],
"text_urls": [
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[],
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]
} | [
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| [
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|
|
jo6vs9 | iPhone Labeling | Technology | explainlikeimfive | {
"a_id": [
"gb62nfa"
],
"text": [
"iPhones are status symbols, showing a big version number is like placing the year on a BMW. The user doesn’t want it, and they’ll buy the newest one just because they can."
],
"score": [
4
],
"text_urls": [
[]
]
} | [
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| [
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|
|
jo8l03 | Why is a CPU dead after one tiny pin is deformed, and why does it have so many pins? | Technology | explainlikeimfive | {
"a_id": [
"gb6d8z7",
"gb6ddma"
],
"text": [
"Not all the pins are used, but every pin that is used for data will cause non-function if it's deformed. There are so many because there are many, many parallel address and data pathways, hence the 64-bit term. If one of the 64 pins carrying your data is bad, one out of every 128 bits of program will be wrong. That's an error every few instructions. You can run like that.",
"Those pins are the only input and output from the cpu. Each pin has a specific purpose and if one is broken then some thing will go wrong."
],
"score": [
4,
3
],
"text_urls": [
[],
[]
]
} | [
"url"
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| [
"url"
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|
|
jo8q8x | Why do print newspapers like The New York Times have page numbers written like A30 A40 instead of just the numbers from 1 to 200 or 300 as the pages may be? | Technology | explainlikeimfive | {
"a_id": [
"gb6en4n"
],
"text": [
"The sections are designed and printed in parallel. They don't know how many pages the A section is when they print the B section as the A section has late breaking news and the front page. Some features sections are printed days before. Restarting the numbers makes for many fewer mistakes."
],
"score": [
7
],
"text_urls": [
[]
]
} | [
"url"
]
| [
"url"
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|
|
joe2yg | Why does a video open faster in the YouTube app than it does in the Safari Version of YouTube ? | Technology | explainlikeimfive | {
"a_id": [
"gb7uorl"
],
"text": [
"When you open a video in the YouTube app it only has to download just the video itself. The app already contains the code for the YouTube site, the player, etc. (also possibly because the app can use more optimizations by virtue of being native code, but not positive on that) When you open a YouTube video in Safari, before it can even start loading the video it has to first download the code for the YouTube site/player/etc as well, that code then has to load the video, etc. so there are more network requests involved."
],
"score": [
3
],
"text_urls": [
[]
]
} | [
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| [
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|
|
joeeod | How in the living hell does a camera work in a way that my common folk brain can comprehend? | Technology | explainlikeimfive | {
"a_id": [
"gb7gled",
"gb7t47s"
],
"text": [
"Light goes through a lens which concentrates it onto a small light-sensitive area at the back of the camera--in old cameras that was a chemically treated photographic film, nowadays it's more likely to be an electronic sensor. There's a shutter in front of the light-sensitive film which opens (briefly) when you press the button, allowing the light to reach it and imprint the image onto it, or the sensor is switched on briefly on electronic ones to have the same effect.",
"camera sensors are like small solar panels, they convert light to electricity. If we measure the electricity, it's like counting photons."
],
"score": [
9,
4
],
"text_urls": [
[],
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]
} | [
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| [
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|
|
joge6a | Why NASA is so much concerned about finding water on other planets or moons? | Technology | explainlikeimfive | {
"a_id": [
"gb7rlju",
"gb7r7vg"
],
"text": [
"It makes possible stations on those places a lot easier if we don't have to bring all of our water. Also, more importantly, water can be turned into rocket fuel, making it easier to set up those stations as waypoint onto even farther destinations.",
"On earth, wherever there is water there is life (sometimes extremely weird life). The working hypothesis is that, if we can find water on other planets, there's probably some form of life there. It's inductive reasoning, sure. But so is the basis for the belief that the sun will rise in the east tomorrow."
],
"score": [
9,
3
],
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| [
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|
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