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ec79gs | When you make a money transfer from one bank to another and the money has already left one account but hasn't appeared in the other, where is that money exactly? | Just wondering... | Technology | explainlikeimfive | {
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"Its my understanding that while it is debited from one account, until it actually posts (is credited) to the other account, the original bank still has it. However, its marked as debited as to ensure you can't use those funds that are being transferred during the transfer process."
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ec7ugc | Why do broadband boxes need resetting so often to get the best speeds? | Technology | explainlikeimfive | {
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"Speed for cable modems is generally determined by \"channels,\" each channel can carry a certain amount of data, and your total speed is determined by how many active channels you have up. When you power up the modem, it negotiates with the ISP side to determine how many channels you're allowed to have, and how many are actually usable (that is, no interference or other problems on that particular channel frequency). After that initial negotiation, if one of those channels does develop a problem, the cable modem drops that channel, which has the effect of slowing the max speed down. I'm not an expert on DOCSIS protocols, but I don't believe they're particularly great at re-establishing on the fly, so the overall effect is that if there are occasional line problems, you'll likely slowly lose channels until you reach a point where you just reset the modem as the fastest way to restart the negotiation from scratch."
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ec812g | Why are batteries in electronics usually placed next to each other with their charges at opposite ends? (ie. +- /-+) | Technology | explainlikeimfive | {
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"By connecting the +- they get connected in series which increases the total voltage You can also connect them in ++/-- manner they are called parallel which increases capacity. For instance in an ebike increasing voltage given to motor increases its speed but increasing current capacity by connecting in parallel increases its range",
"When connecting batteries in series, so their volatges add up, you connect the negative of one to the positive of the next. This is easier if they're alternating directions. Then you just run a short metal strip between the positive of one and the negative of the next, which are now right next to each other and almost touching. If all the positives were at the same end, you'd have to run a wire all the way down the length of the battery and over to get from one positive to the next negative. Why do we have to add them up in series? Batteries have a set voltage, like an AA is usually 1.5 volts. If the electronics need 4.5 volts, they just require 3 AA in series (end to end, positive to negative). This way they don't need a separate unique battery for every electronic device that needs a different voltage, they can just add up existing batteries in the numbers needed. What does connecting batteries in parallel do? Instead of adding voltage, they keep to voltage but add current capacity(how long they can stay on) So if you had a type of battery that was 1.5 volts and lasted for one hour drawing a specific amount of current, 3 of those in series (end to end, positive to negative) would provide 4.5 volts for that one hour, where as 3 in parallel (all positives hooked together and all negatives hooked together) would only provide 1.5 volts, but for 3 hours.",
"It's about the layout of the connections _between_ the batteries. The goal is to get one end of the battery to connect to the other end of the other battery (+ touching -). But...if you're space limited and don't want them in a long line, you have the installer place them in the fashion you describe and you have a short-path for your connection between the + and - ends. This is because to get the overall desired charge from the batteries you've got to run them in a serial configuration.",
"Most batteries put out 1.5 Volts while most electronic devices require higher voltages to operate, like 6V. The easiest way to get 6V from regular batteries is to put 4 of them in series, like so: -+ -+ -+ -+ with the positive terminal of one battery touching the negative terminal of the next one. But since that would make the battery compartment too long, they put them like this instead: -+ +- -+ +- and then add a little metal strip that connects the positive terminal of the first battery to the negative terminal of the second one and so on. This is easy to do because the terminals you need to connect are right next to each other. If the batteries were all facing in the same direction, like so: -+ -+ -+ -+ then you would have to run wires from one side of the battery compartment to the other side to connect them in series. This would make the assembly process of the device more complicated."
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echd5g | How does the camera’s autofocus know when the image is sharp? | Technology | explainlikeimfive | {
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"It's sharp. OK, that's not going to be good enough. The autofocus computer examines adjacent pixels as it adjusts the lens. Some adjustments make them more alike, and others make them more different. The lens position where the pixels are the most different from their neighbors is the sharpest, so that's where the picture is taken."
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ecide4 | Why can computers delete all data and where does it go? | Technology | explainlikeimfive | {
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"Something can be truly gone on a hard drive but not quite how we are shown it to be gone. If you delete something you have told the drive that that space is free for something new, however, until something new is written over it it is technically still there just not accessible any longer, at least not easily. For example, if you want to delete evidence simply deleting it from the drive leaves that information there to be recovered by a professional, however, if you delete it and then fill that drive with new data that deleted data is now completely gone and as far as I know can it be recovered.",
"Imagine a bunch of tiles on a floor. That is your data. Then imagine a notebook with information saying file A is in tiles 1,2,3 and file B is in 7,8,9. When you delete file a, those tiles didn't change. You simply erased the line in the notebook. That's why the fbi can recover deleted data sometimes. The tiles are still there unless a new file was added (new notebook entry C) taking tiles 1,2,3. The thing is, when the new tile is placed, the tiles are modified. There are apps that can \"clean\" unused tiles for security purposes.",
"When a program is \"deleted\" the section of the hard drive it took up is marked as \"safe to overwrite\" and any links to that data is removed from the computer. Then when the computer is writing info to the hard drive again if it needs to it will overwrite the data that was there. At that point the data is truly gone because what was once there is now actually removed. If the computer hasn't gotten around to overwriting it yet then it can be recovered which is what happens when someone says an expert recovered deleted data from a hard drive. It is possible to run programs that overwrite the deleted data with just zeroes or with jumbled words. This is called \"data erasure\" and there are multiple techniques to achieve this but they all operate on the same principle of overwriting the data marked as deleted. There are some exceptions with specific older formats or solid state drives, but in general this works."
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ecil9z | How do they give 3D printed organs functionality? | Technology | explainlikeimfive | {
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"text": [
"The organ printing is just a framework around which they can then grow the cells an \"organ skeleton\" if you will."
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ecjcth | How did studios able to upgrade old MV to 4K on Youtube (especially Last Christmas by Wham)? | How difficult is the conversion? | Technology | explainlikeimfive | {
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"Actual 35mm has a expected resolution of approximately 4K so it's just a matter of doing a new transfer from the film to digital media. So there's really not a whole lot involved it's just a matter of scanning the film in at the higher resolution."
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ecjj6i | With the release of Last Christmas in 4K, how are old music videos that are so low in resolution remastered in 4K? | Technology | explainlikeimfive | {
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"The original was shot in very high quality to physical film (35mm probably) and then was compressed for the media standards and capabilities of the day. They just get the original footage and compress to 4k instead of whatever the first release was. They may haved digitally altered the colours to make it more saturated etc"
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ecklb8 | How does "on-board WiFi" work for buses while there are rural areas that can't get internet at all? | Technology | explainlikeimfive | {
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"I'm no bus expert but I assume it's a [mobile hotspot device similar to these]( URL_0 ). They work like the data on your cell phone, routing traffic through nearby cell phone towers. I know some people that are in rural areas or live in an RV etc. use these instead of the usual hookups.",
"WiFi is a way to connect computer devices together via radio / without the computer cables that were common in the 1990's (and still are). In order for the WiFi network to \"get internet\", the bus must have a mobile hotspot, similar to a cell phone, but for data, to basically connect to \"the internet\". So if the bus goes through a rural area without cellphone tower coverage, the computers and phones on the bus can still talk to each other / play a LAN party game, but they lose connection to the internet. It is possible to get internet access via satellite, but it's more expensive and unlikely that the bus will have something like that."
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ecqawm | How does a camera's focus work? | Technology | explainlikeimfive | {
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"Picture the classic 'light through a lens' diagram of lines converging after passing through the lens. At the point where the lines converge you have perfect focus. Either side of that, before they converge or after, is out of focus. Moving the lens back and forth alters where the focus point falls. Camera autofocus systems move an element (a lens consists of multiple glass elements) back and forth in increasingly fine degrees until the point of convergence, and thus sharpness, falls on the sensor itself."
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ecrep0 | Why do you not need RAM equal to the size of a program to run it? | I'm thinking of games, mainly. Why is 16gbs of ram enough to play a 130gb game, like Asgard's Wrath? | Technology | explainlikeimfive | {
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"Because the only entire game is not loaded into memory, only the executable or game engine and game assets needed for what you are looking at.",
"Ram is like a high speed but low capacity storage system so basically it only stores what the computer is going to need next and not the entire game once that data has been processed the memory wipes itself and loads the next lot of data",
"A game is not a single file. The executable (i.e. the code) is loaded into RAM and based in your actions loads resources (e.g. textures, music, ...) only when they are needed. In other words, you do need enough RAM to load the whole program, but that is only a small fraction of the size of a game.",
"Most games load all the data from a level into RAM, so the designers have to make sure that each level only contains as much stuff as they can fit in there. That is the main reason most games come with level transitions: as you enter a new level, all the new assets that are needed in the level are loaded into RAM. With open world games where you can travel without loading times, developers need to be a bit more tricky. For example, Minecraft divides the map into cube shaped \"chunks\", loading only nearby and visible chunks into memory and discarding distant chunks if they occupy too much memory. The Elder Scrolls uses a similar approach, dividing the map into what they call \"cells\", loading them into memory as the player comes close. If this does not happen fast enough, objects can suddenly pop into view as you come close. GTA IV for example had this problem when driving fast cars, with cars and other obstacles appearing out of nothing, sometimes right in front of the player. The older GTA games even often unloaded things from the memory to make space for new things, for example cars and people vanish if you look in a different direction.",
"Because why load level 8 when you're on level 2?"
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ecrzvp | What are AMP pages and what's bad about them? | Technology | explainlikeimfive | {
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"AMP has two basic components: 1. A way of writing small web-pages 2. A way of caching/loading those small web-pages to make them quicker to load. Most web-pages nowadays are large and bloated. For example i just refreshed the home page of reddit and it made 168 requests and download 18MB of data. This is usually okay, but for mobile phones, especially in less built up countries that can be troublesome. Both data limits, and also battery life can be affected by constantly loading these large pages. AMP provides a tool-set for making very simple, quick and small web-pages. To prevent bloat AMP is deliberately limited in what it can do. An example; [this]( URL_1 ) article transferred 2MB of data from 50 total requests. [this AMP]( URL_0 ) article transferred < 1MB of data from 32 total requests. However No.2 is where the controversy comes in. In order to use the AMP tool-set you also need to agree to allow anyone to \"cache\" the AMP versions of you web-pages. This means that they can take a copy of the page and direct people to that copy, rather than the original version on your web-site. The reasoning in here is that it can be quicker to access a cached copy of a page that's included on a site you're already visiting, rather than having to go to an entirely new site. This reasoning is true, but skips over the main detail which is what most people are concerned about. AMP is essentially entirely Google-driven. When you click on an AMP link on a google search result they're showing you the page directly from Google. You never even visit the web-site you think you're visiting. In this way Google as access to more of your total browsing data. AMP pages also make it easier to \"get back to Google\" and click on other Google links, whereas if you've clicked through to a news organisation's web-site then you're more likely to stay there and click on more things for them. You'd think that if AMP was so bad for the other web-sites they just wouldn't participate it in, however because Google has a monopoly on search. And because they prioritise AMP links above non-AMP links the other web-sites feel forced into it. One final thing. AMP is written by Google, but it is an open standard. Anyone can do the same caching of AMP pages that Google does. However some see it as abusing their monopoly in the world of search to gain more control over the web.",
"This [post]( URL_0 ) from /u/amputatorbot explains it well, I think. The short version: it’s a threat to the open web.",
"My understanding is that the bad-ness is Google continuing to abuse their monopoly in search and reshaping the wider web to their desire. AMP pages will be loaded from big-G's severs so 3rd parties will see fewer hits which may make whatever corporate structure that governs them see them as less successful and could cause them to be discontinued. Eventually there could be no source material for Google to effectively steal?",
"Leaving this here for people to find: Firefox has a \"Redirect AMP to HTML\" extension URL_0"
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ecti3p | Wham's last Christmas in now in 4K, how is this possible? | Technology | explainlikeimfive | {
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"35mm film is generally estimated to be somewhere between 4k and 8k in resolution. So you scan a new copy from the archived film footage, at 4k resolution. Not all old footage was filmed with 35mm film. Some stuff was shot on 16mm (generally estimated to top out around 2K) other was shot on video (worse perhaps between 480p and 720p). Scanning a new copy doesn't add information that wasn't captured originally, but one of the most popular media to capture video was film so in many cases you just scan a better copy.",
"Up until quite recently movies were shot on film instead of digital cameras. Film does not have a pixel resolution like digital cameras but it does have grain which is similar in nature. So comparison of digital resolution and film grain is not directly possible. And they might have used different types of film depending on lighting conditions as lower grain film is better in dark scenes. But the film used in movies which usually had very brightly lit studios or were filmed outside in the bright California sun with reflectors to get it even brighter were usually very high grain film stock. This gave a very good quality picture which really showed off when projected on big screens in movie theaters. Even today with 4k scans of this film you get more artifacts from the \"low\" resolution of 4k then from the film grain. And this is why film studios were slow to adopt digital cameras before they could get good high resolution cameras as film were able to capture more details."
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ecwmju | How does nuclear early detection work? | I know thermal detection looks for high temperature spikes that are equivalent to a nuclear launch, but how does it tell the difference between say a saturn5 rocket and a nuke? Do they make a spaghetti model on possible targets? How would we know what their target is? | Technology | explainlikeimfive | {
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"Launch site, direction, and publicity. A civilian rocket will come from a space center and be advertised beforehand. It will then immediately start to curve and pick up horizontal velocity.",
"The weapons are called Intercontinental ballistic missile for a reason. Ballistic that they are for most of the time unpowered and will just follow the path that gravity dictates. It is not that different from if you throw a ball, fire a rifle or even better a bottle rocket. What you hit depends on what speed it has and in what direction they move. The principle is the same when you throw a ball to hit a target. A US Minuteman-III ISBM is powered for around 3 minutes and would take around 30 minutes to hit a target in Russia. So it is the only powered for 10% of the flight. They have multiple-warhead that can hit multiple targets but there is a limit of how far apart they can hit the ground. Even during the power part you need to point in the correct direction. So if you just had the launch direction you get a single line with a potential target. You could likely see the difference between a Saturn V and an ICBM because an ICBM is a lot smaller. The main way to tell the difference is where they are launched from, in what direction and how many were launched. Launches is in general not secret and since 1971 US and Soviet Union had an agreement of notification of all launches. The location is also relevant because a launch from a space center is normal but launch from a missile field or a sub out at sea is not. For a test, you do not launch stuff that will hit \"enemy\" terror but a missile test range. Russia test from north of Moscow the Kura Missile Test Range on Kamchatka, north of Japan. The US launches from Vandenberg Air Force Base in Califonia to Kwajalein Missile Range in the Pacific Ocean. So test-launched is not in the direction that could the the \"enemy\" The launch direction for most satellites is towards the equator so the orbit will not be directed toward the target. In most cases, an ICBM is too weak to launch in payload into orbit so US Minuteman-III ICBMs have to be launched over the pole to hit Russia. It is also unlikely that you would fire a single nuke against the enemy with the exception of perhaps North Korea the might not be able to launch more. If Russia launched a Nuke towards the US and it was detected at that or in the worst case when it hit the target. The response would be the launch of a lot of missiles. So you would not start a nuclear war with just one missile as you loos any element of surprise on all other targets. Any first strike would likely be massive.",
"> how does it tell the difference between say a saturn5 rocket and a nuke? It doesn't. This is why all space rocket launches are announced in advance. Early space rockets were ICBMs, there was no difference between them so the systems just treated all rockets as potential nukes Once the rocket is going up it's quickly tracked by radar to figure out it's course and speed and determine potential targets",
"it doesnt if you wanna launch a rocket into outer space you have to disclose the information about it to your nuclear \"adversaries\" in advance specifically to avoid tripping their early detection systems.",
"Rocket launches are disclosed, precisely to prevent this sort of confusion. If you see a rocket launch that's not on the published list, that's cause for concern right there. During the boost phase, while the rocket motor is making a lot of light, observation satellites can track it and figure out where it's going. The path is controlled by ballistic physics, go really fast and you end up at the ISS, go slower and you drop back on Washington. Nobody's going to buy the \"don't shoot down our scientific rocket just because it has a ballistic path toward your capital\" story. That's what the missile defense folks have been itching to demonstrate for years.",
"There's no way to tell an ICMB from a normal rocket just from the launch. You have to look at the launch site (i.e., if it's launching from Cape Canaveral or Baikonur, it's probably just a rocket. If it's coming from a known ICBM silo, you're in trouble), and to know in advance when countries plan on launching rockets. Rocket launches disclosed and highly publicized specifically for that reason. Countries *want* other countries to know when they're launching rockets so there's no confusion (with the exception of North Korea). Once it's been in flight for a bit, you can plot it's trajectory and see if it's going to orbit or if it's on a ballistic trajectory, and if so, to where."
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ecykdi | All things that happen in Internet are generally instant, why then changing DNS configuration can take up to 48h? | That's ages in web timeframe! Is human factor to blame? | Technology | explainlikeimfive | {
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"DNS records have a TTL (time to live) value. This value is the number of seconds a server that caches the record should wait before rechecking the authorititive server to see if it's changed. If a DNS change is taking 48 hours, that means the person making the change did not lower the TTL value first (of course this change would take 48 hours to propogate, but the subsequent change would then be quicker.) The usual low value people use is 300 seconds.",
"This is called \"propagation\" and is a thing whenever caching is involved. Caching is just storing information in a quickly-accessible manner to improve performance, but in order to make it high-performance it is only updated periodically. DNS cache information can be stored locally as well as on DNS Servers (such as those operated by your ISP). The DNS entries stored in cache have a TTL (time to live) value, during which time the server will use the value from cache rather than looking up any updated value from somewhere else. Once this expires, any new DNS query will have to be completed normally - it's at this point that any new, updated value is used and then stored in the cache again. DNS changes can take up to 72 hours to propagate fully because of this."
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ecyz0p | Back in the day when watching scrambled porn (Playboy channel, etc) why did the white backgrounds/white scenes result in almost no scrambling vs dark scenes (which were extremely indiscernible). | Technology | explainlikeimfive | {
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"Back in the day it wasn't true scrambling. It was messing with the video sync or something along those lines. The white background had a higher signal level which improved the signal.",
"Wow, takin' it BACK son. Haha oh man. Me and the homies, some Jolt cola, turn it to channels 98 and 99 baby. Flip between the two of those and pray like hell for some magic to shine through. Sometimes, it sure did. It sure did."
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eczo4a | How does Windows Explorer copy, move, and replace files? What would happen to the files if the operation was interrupted? | Technology | explainlikeimfive | {
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"This is a tough question to answer, mostly because \"files\" and \"folders\" are abstractions built to make data access easier for humans, and also because there are lots of variables that come into play, and many levels of abstraction that are all accomplishing something different. At a very low-level: If you move data across hard drives or logical partitions (basically from one drive letter to another), the file will get loaded into RAM and a write instruction will be issued to the controller of the new storage medium which will take the data out of RAM and store it permanently; it will then be marked on the original storage medium that the space taken up by the file is OK to re-write (aka: deleted) If you're moving to a new folder on the same drive, Windows just updates the metadata of the file to say that the correct file path for it is the new path, rather than actually changing anything physical on the hard drive with regards to the actual file data. Copying is the same as moving across hard drives, except that it is the same no matter if you're copying to a new drive or to a new place on the same drive, and at the end the original file isn't deleted. Replacing is *kind of* an erase and immediate overwrite, but since the erase doesn't change the underlying data, it really just adds or changes the bits in the data that changed with the updated file. All writes to a hard drive follow the same basic process: for each bit in the raw machine data, check the bit the read/write head is on (in a HDD this is a tiiiiny area of a metal disc that is rotating), if it doesn't match what the file calls for, flip it from what it is to the only other option (because binary), then move to the next bit and repeat, until we get the command for \"end of file\". Reads are similar, but it's basically \"from start of file flag to end of file flag, read each bit and stream it over to the RAM and CPU so that it can be used\". If the operation is interrupted, depending on which operation and where it was when it was interrupted, you would probably corrupt one or both files (though both is very rare)."
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ed110n | if RAM is ridiculously faster than even the fastest SSD then why aren't we using RAM for storing all of our data instead of hard disks and SSDs? | Technology | explainlikeimfive | {
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"text": [
"1. Nice idea to store your data in a device that requires constant, completely uninterrupted power to not lose it's *aaaand it's gone*. 2. Type | Price ---|--- 1TB HDD | 44$ 1TB SDD | 110$ 1TB DDR4 RAM | 3120$ See the issues?"
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ed3pft | How do the PC WiFi USB sticks work. | I was looking on amazon and noticed these WiFi usb sticks. They boast high speeds for low costs, so I was wondering if they actually have $30 high speed WiFi with no additional cost or simply provide a faster connection to my previously existing WiFi. | Technology | explainlikeimfive | {
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"text": [
"Uh......before OP goes out on shopping spree. WiFi doesn't get you internet. WiFi gets you connected to the base station which has landline internet access. WiFi is not a magic no cost replacement for celullar internet",
"Nothing will make your speeds faster than what your provider/bandwidth allow. That is, of you get 10mbps at your modem, nothing will make that faster. Now, the USB sticks are basically external wifi antennas. They can be more powerful than built-in antennas in older computers, but are generally meant to be used with devices that don't have built-in wifi capabilities (like desktop and tower units). When they say high speed, they simply mean that the USB device can transmit and receive data at a rate comparable to a Ethernet (or Hardline) connection."
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ed4biq | What does a CPU actually do for a computer? | Technology | explainlikeimfive | {
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"text": [
"The CPU IS the computer. In other words, it is the component responsible for all the computing.",
"All programmed instructions have to go through the central processing unit (CPU). It handles all of the computations and can instruct other programmed instructions to go to other sub-systems like your memory, storage, video cards. It’s speed is dictated by how fast it can perform these commands denoted in its clock cycles in this modern era of computing we call GHz or gigahertz or billions of cycles per second. That’s what the cpu does. It’s the brains of your computer.",
"The cpu is the central processing unit. It's the brain that all other parts is connected to. Everything else is done at the instructions and data generated by the cpu. All of the above and everything is the weight answer."
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ed4bjr | How does an automatic cash counting machine works? How does it identify the different denominations for different currencies? | Technology | explainlikeimfive | {
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"Machines that verify that bills are real often make use of a light that shines through the bill so that all the layers and watermarks blur together into one image. And then they \"snap an image\" and compare that image to a set of known bills. The comparison process works something like this: the bill is divided into ten strips that are compared individually. If all the strips are similar enough to one or several reference images, it counts as a pass. If all the strips pass, the bill is approved. Some safety details are more important, and those sections are more important to get right. How do you create the reference image memory? Reasonably easy. You call your central bank and order a set of \"reference money\". Basically a wad of cash that shows varied, acceptable wear. Because if there is one thing people are not, it's careful with their money. The machine wants to accept worn money, and refuse counterfeit money. It needs to be taught what newly printed money looks like and what old, worn money looks like. It's taught by looking at approved, worn, money. One at a time. If it should be able to handle different denominations of different currencies, it's basically a matter of having a larger reference image library so that the machine can handle all kinds of shit at the same time.",
"I believe by the location of the strip inside the bills. If you hold a bill up to the light, you’ll see a strip running down it. All bills have them in different places (I think dollar bills don’t have them at all). Someone correct me if I’m wrong !"
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edbhql | How are game engines and text editors for them made? | Technology | explainlikeimfive | {
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"text": [
"They're coded just like any other program. In the case of game engines and the like, usually with some flavour of C."
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edfr2o | why we changed from old fashioned battleships to modern day destroyers? | Technology | explainlikeimfive | {
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"text": [
"Until about the mid 1930s naval gunfire was the primary way to attack ships. In the 1930s and 40's naval aviation surpassed guns as the best way to blow shit up from the sea. Planes are more flexible, and have much longer range than guns, and by the 1960s cruise missiles could do anything a big gun could do better and cheaper. Because battleships were *insanely* expensive to produce and operate pretty much everyone immediately scrapped theirs after WW2. The big guns were no longer worth what it cost to keep them at sea. Modern destroyers, frigates, and cruisers usually maintain one or two small or medium caliber (75-130mm) guns for engaging aircraft, small boats, and providing shore bombardment, but missiles are now their primary offensive armament.",
"1) carriers. Pre WW2 the longest range and there by way of projecting force was shooting things. Then when we got planes we could go further from our ships to hit things. So gun boats are primarily support ships now 2) missiles. We no longer require huge tonnage ships to sport massive guns to get range or impact. We can fit just as good of a strike package on many smaller ships and not have all of our eggs in one basket, so to speak. 3) defensive capacity. Until around WW2 a ships defensive capabilities were measured by how many hits it could take, so that meant bigger ships to displace for thicker armor. In the modern Era speed, and small profile, is much more of a defensive tool (thanks to computerized tracking weapons) than thick armor. And many other reasons that fit the bill similarly."
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edi2b7 | How do debit cards instantaneously receive funds via online transactions? | Technology | explainlikeimfive | {
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"Your card is just a tool to access your account, it doesn't know how much is there or anything apart from some numbers that link to your account. So when you use cashapp, that tells your bank account that theres more money gone in. Then when you use your card, the retailer's machine contacts your bank and asks if there is enough money available."
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ediiqw | How come sometimes if a video isn’t loading at the beginning, if you just move the cursor a couple of seconds to the right it will start immediately with no lag? | Technology | explainlikeimfive | {
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"Typically what happens is your web browser will abort its current request for the video file and start a new one offset by the amount you seek by. The new server you connect to is performing better than the one you were at before - or maybe the other one had just crashed - and you get your data quicker. When you're a big company, you can provide the illusion of an always-working web site, but things still break. They've just got it down to the point where this is what goes wrong rather than the whole site being down or whatever."
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edk8p3 | Why does Google Chrome use up so much RAM? | Looking at my task manager, it shows Google Chrome (21). Is it that it is operating 21 different things in the background, or is it hiding every instance except my own? Truly I would love to know for the sake of my PC. I launch Google Chrome and sometimes my fan starts kicking up hard. | Technology | explainlikeimfive | {
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"text": [
"Each tab runs independently so that a crash in one does not crash the browser. It is like each tab you open is a new application.",
"because you have RAM to use. there's no reason to not use more ram if its being put to good use. it's better performance to load everything into memory for best fast responsive access. every tab runs on its own. there is no shared memory. that's for security sake, not speed or memory."
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edn5my | How do languages with many characters like Chinese or Japanese fit them all on their keyboards? | Technology | explainlikeimfive | {
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"text": [
"They don't. They type syllable or simple radical to spell out the characters. It's like if you want to show the character β you spell 'beta' and there's drop down menu listing possible character for the word 'beta'."
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edooe8 | What are gamma values in pictures and why does it affect png (aka make it worse than jpeg?) | Technology | explainlikeimfive | {
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"This comes from the days when computers were much slower and monitors were huge and heavy boxes with thick glass on the front of the screen - the CRT, or cathode ray tube, uses intense electromagnets to shoot tiny bits of stuff at a screen that glows when hit by this stuff. That's how it makes colors and pictures, by changing how the stuff is fired at the screen and by aiming to make flat lines to cover the whole screen down from the top, 30 or 60 times every second. When this was going on, in the earlier days of computing, we hadn't figured out how to make colors exactly the same from Mac os and Windows and other computer operating systems. When we tried the normal way they looked different, and that did not work for us. So we tried to use this gamma value to preserve the color we would see on the screen from one device to another to make them match. But something went wrong when not everyone agreed on how or even if they wanted to use it at all. So all sorts of things happened, some devices used it right and others did not. It was a mess! The gamma value specifically tells the computer how much of the color to show, from none to all of it or possibly even more. That's because the gamma was used to say 'this device is already showing more green and red and blue than the one that made the image, so turn down the colors of this image so it looks right on this device' or 'this device naturally shows less green and red and blue than the one that made the image, so turn them all up to match'. Over time we realized how silly this was and fixed the problem in a better way so everything matched all the time outside of gamma images. Now the gamma value is a leftover of what was tried before, and most browsers don't use it or have a default set up to work in most cases. Better or worse depends on what you're doing. PNG is designed to be good on websites, so it can get smaller than a jpg or gif with the same picture. But not all browsers support it the same as jpg or gif formats, there are still old browsers out there still using the gamma values or trying to. Because of that it is a matter of knowing who will be using your site and images - if you need to use the old stuff jpg may be a better bet. If you have all new stuff png may work better. When you make new png files, the gamma can be left out to make it like a more efficient jpg format. Great question!",
"Your eyes don't work on a linear scale, what that means is that your eyes are much better at picking out slight differences in the shadows, than they are are picking out slight differences in highlights. Let's say that your eye perceives the same change in intensity of light every time the light level is doubled. Imagine yourself in a pitch black room with a small birthday candle as your only light, and imagine how much light it casts on the walls. Now light another birthday candle and hold them besides each other. The amount of light has now doubled, and it'll be fairly easy to tell the difference in brightness between the one candle, and the two candles. If you want to add more candles to perceive an equal increase in brightness once again, you can't just add one more candle (3) you need to double the amount of candles you have lit, so you would need 4.... then 8, 16, 32 etc. If you brought in a powerful torch and pointed it at the wall, and then lit a small candle as well, you're not going to see a difference, even though there technically is one. So that's the human perception bit covered... On to computers... We store images in bytes, typically 3 bytes per pixel, one byte for red, green and blue, but for the sake of discussion let's just deal with green and treat it as if it was converted to greyscale. 1 byte gives us 255 different possibilities we can use, ranging from 0, which is the darkest dark, to 255 which is the brightest bright, and we have to somehow map every other brightness into that range. If we stored it linearly and said... the top half brightness, we allocate to 127-255, and then whats left over, we divide by 2 and use the second half of that for the next top half of brightness... so 64-127... and then divide whats left by two and use the second half... 32-63. Notice how every time we try to store a number representing a darker brightness, we have less numbers we can use to store it. But if we go back to the top, that's not how our eyes work. we can see much more detail in the shadows than we can in the highlights, because in the shadows, the perceived change is much more apparent, because it only takes a small amount of extra light to double the amount. If we stored the value as originally described, we would be dedicating the majority of our storage space to differences in brightness that we can't tell the difference of very well, while starving the most useful ranges in which we can tell a difference. And finally, this is where gamma comes in. Gamma is a mathematical function that either compresses or expands the brightness so that each doubling of brightness gets roughly the same range of numbers to store its data in. So instead of the top half of the most bright colours getting half of the entire range, they might instead get a range of 24 numbers allocated to it, and the range between that, and half as bright, might itself only get 24 numbers allocated to it, and the half as bright as that... 24 numbers, so on and so forth. That means that when you get to the really dark bits, what might have previously only had a range of 1 or 2 numbers, now has a range of 24 numbers, that means it can store much more detail... but here's the important thing to remember, your eyes can *perceive* that detail. That's storage.... when it comes to displaying the image, it goes the other way, and your monitor applies a gamma factor in reverse, a change of 64 to 88 (using the 24 range for a doubling of light) actually does end up as a doubling of light coming out your monitor. I feel like I have rambled and not been particularly clear so... tl;dr - Storing information about the shadows is more useful to the human eye than storing information about the highlights. Gamma is a way of allocating more data for those useful shadow values than we otherwise would if we stored the absolute value of brightness instead."
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edqq83 | Why aren’t there more alternatives to plastic water bottles? Is it entirely economic or are there no good materials? | Technology | explainlikeimfive | {
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"Plastics were the revolutionary space-age material when they first became ubiquitous. They provided the answer to the analoguous question people were asking at the time: \"Why aren’t there more alternatives to glass water bottles? Is it entirely economic or are there no good materials?\". A PET bottle is extremely lightweight, low-cost and almost unbreakable under normal circumstances. It is a true marvel of modern materials science.",
"It's almost entirely economical, just because plastic bottles are VERY cheap. Also they are incredibly easy to manufacture and have a lengthy life span",
"Reusable water bottles are the most economic and environmentally friendly choice. There are bio plastics that are much kinder to the environment but there hasn’t been much widespread implementation. As of now plastic is actually better then a lot of other materials, for example glass has a much larger carbon footprint to produce.",
"Because it is very very good for the purpose of making water bottles. Cost certain factors into how popular and good a product is. Plastic is strong, flexible, resists shattering, can be tinted, is relatively easy to manufacture, safe (mostly). Plastic liquid containers have saved a lot of lives (think about things like plasma bags and saline solutions in emergency vehicles or packaging and preserving food/drinks for people who go to difficult places) There are good reasons glass replaced metal, clay and wood and also good reasons why plastic supplanted glass containers. There is a lot of work that can be done to improve plastic but dollar for dollar, it is also fairly energy efficient in terms of production. Hence it isn't easy to find alternatives."
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edu7de | What does actually happen inside a computer when it crashes or buffers? | Like if a program freezes, why does that happen How does it actually manage to get stuck and reacts with a blue screen of death? | Technology | explainlikeimfive | {
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"Crashing can occur from many things but usually occurs when the program encounters 'exceptions.' Modern programming often has 'functions'. Think of a program making toast. You rarely write a program to make the toast all in one go, you instead split it into functions. First you get bread. Then you get butter. Then you put the bread in the toaster. Then you turn it on. Then you wait. Then you take it out. Then you butter the bread. If any of those functions encounter an exception, it disrupts the flow of the other functions. What if there's a power cut - you can't turn the toaster on, which means every step beyond that is now useless - that can be thought of as an exception. In programming, most of the time exceptions are planned for and the program should know how to handle them. If it doesn't, that's when it'll crash. It simply crashes because at one stage of a process, something unexpected happened and the programmer didn't implement anything to let it recognize that. Buffering is very different from crashing. A buffer in programming is just a medium between data when you move it. Think of the toast example - the plate is essentially a buffer - it's just there to hold the bread while you move it from the bag of bread to the toaster. A program may use a buffer to store outputs temporarily if an input can't receive them quickly enough, such as your browser buffering a video in advance because YouTube is sending you the video faster than you watch it."
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edvgd1 | How does a touch screen differentiate between my finger or a stylus and something like a pencil eraser | Technology | explainlikeimfive | {
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"There are two types of touch screens: resistive and capacitive. Resistive screens don't differentiate between your finger, a stylus or any other random object because their sensors react to pressure. Capacitive screens differentiate between all those objects because some (fingers, stylus, even drops of water) conduct electricity, and some (pencil eraser or gloves) don't. Their sensors react to anything that can hold an electrical charge. Hope that helps!",
"The touchscreens that will work for your finger but not a pencil eraser work by sensing electricity conducted through your fingers. A stylus is built to conduct the right amount of electricity for the screen to pick up on it; a pencil eraser isn't. That's also why your touchscreen won't work if you have gloves on, unless they're specially made for using with touchscreens. There are other types of touchscreens that just sense pressure on the screen, and those *wouldn't* differentiate between your finger or a pencil eraser."
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edy0qn | If videos can play and load at 60fps, why do photos take any amount of time to load? E.g. Video loads 300 frames for 5 secs, but can take 5 seconds to load one 'frame' (picture) | Technology | explainlikeimfive | {
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"Because you aren't loading sixty photos in a second. You are loading one photo, then a series of changes. Those changes keep coming for a while until there's another whole photo. That's why you get mangled video sometimes if you jump forward - it tries to add those changes to the wrong starting point. Then it all snaps back when it gets another whole picture.",
"I'm not sure what you mean by \"load\" since it can have different meanings depending on the \"technological context\", so I'll assume a simple one: You have image files and video files in a folder on your computer. Your operating system (Windows / Linux etc.) knows that the file you clicked has to be presented with a software that knows how to display the data as an image or a video (e.g Photo Viewer / Media Player). It then takes time for the software to be loaded from the hard drive (which is slow to access and work with, but keeps your data when the computer is turned off) to your memory (which is fast, but is erased as soon as the computer is turned off). Let's call this time \"Overhead\". Once your software is loaded, it presents the file visually. When you open a video file, all of its data (the frames in it) shares the same single overhead, where opening a bunch of image files one after the other, causes each of them to have its own overhead. But what if your media software remains open all the time, and you occasionally tell it to open different files? There is still similar overhead time for each file to be presented because it needs to be loaded from the hard drive to the memory (just like the media software itself). This creates a similar overhead effect, although in smaller scale. If we look at the context of browsing the internet and loading different files from different websites, there are additional overhead times - in much greater scale. Your computer needs to connect to the server and send a request for the file. The server then needs to send the file to your computer. These overhead times are significantly longer than those described above. If your computer requests from the server a single image file at a time, each image file will cause its own overhead. If it asks for one big file, like a video, it will have the same overhead as a single small image file. This is also why sending a zip containing multiple files takes shorter than sending each of the files separately in succession. I'll note that in practice, in the scenario that I just described, you would actually have to wait for the entirety of the video file to be sent from the server before your computer starts playing it. When considering a video that is being streamed to you by the server, rather than being sent as a video file, the server knows that you asked the video to be streamed and thus it \"keeps sending you more and more frames\" (simplified) - without your computer having to constantly send requests. Thus, there is not any overhead between the video frames being displayed."
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edy9mk | in wireless keyboards and mice, why do replaceable (usually AA) batteries last for over a year while integral rechargeable batteries run down in a matter of weeks? | Technology | explainlikeimfive | {
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"Because the non-rechargeable batteries use different chemistry that has lower self discharge.",
"There are different kinds of batteries for different circumstances. Alkaline batteries are the ones we are familiar with as disposable batteries. They last a long time and can put out a small amount of power over that long time. That's why things that need more power generally call for more batteries rather than bigger batteries. Lithium Ion batteries are rechargeable, capable of putting out a lot of power, and generally don't have issues if the battery runs all the way down to empty. Nickle Cadmium batteries can put out a whole lot of power, but don't last long at all. They charge extremely slowly. There are more types, but as you can see, the various types of batteries all have their pros and cons, so picking the right type of battery for a product requires talking to an engineer who can figure out what the best option is. Phones tend to use Li-ion, TV remotes generally use Alkaline, and airsoft guns often use NiCd."
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edza6g | why is the Windows file system FAT32 inferior to NTFS? | Technology | explainlikeimfive | {
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"text": [
"FAT32 is intended for use by individuals / consumers. It only needs very basic features like \"save this file\" and \"keep a list of all files\". It does not even need to worry about large drive sizes, like you would see at a large company, or being particularly fast. FAT32 is the Kia of filesystems. It's fine. It does what most people need, with few frills or luxuries that would make maintenance harder or more expensive. NTFS is very intentionally built to be \"enterprise grade\". It handles cases that most home users don't have to worry about. Ridiculously large drives. Power outages in the middle of writing to the drive. Multi-user permissions. Encryption. Compression. NTFS is the Tesla of filesystems. It's waaay more car than most people need, but if you need the features and can afford it, it's less likely to leave you stranded. But when it really does break, there are maybe a few hundred people on the planet who can unbreak it.",
"Including but not limited to: * The maximum size of a single file is 4 gigabytes * The maximum size of the disk as a whole is limited as well * No file ownership or permissions can be recorded, which is a big deal for modern Windows systems * None of the other NTFS features like compression are supported All that said, the filesystem has exist since 1998 or so (even older for FAT16 and earlier versions) and is well supported by other operating systems and devices like cameras, etc. It's not appropriate for a whole operating system to run on any more, but it's great for a USB stick."
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ee0gwo | Why are we expected to have super complex passwords, but then very simple security questions which are often public information which can be used to access an account? | Technology | explainlikeimfive | {
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"Because the companies doing that don't know what they're doing. There are a lot of myths and outdated \"recommendations\" and rules that people keep blindly using and it makes services less secure. It sounds stupid because it is. Having restrictions on passwords (beyond minimum length and maybe checking that it isn't one of the most common 1000 or so) has not been recommended for ages. A long password made of simple words is more secure than an 8-character super random password with symbols and numbers. And having simple recovery questions that anyone can use to reset the password (automatically, without access to your email address) defeats the purpose entirely. Source: I work in security.",
"Because not everyone actually understands AND cares about cyber security. That's it. That's the reason. Edit: There can be good reasons for max password lengths, but realistically, max limits should be a few hundred to a couple thousand characters, not in the ballpark of 32, etc.",
"I hate when companies put restrictions on my passwords. Must have upper, lower, only these symbols, max of this many characters. Let me put in my simple yet lengthy random diceware passwords! :C",
"Most security questions have you manually type in the answer when you're setting them up. No one said you ever had to give the *correct* answers. The name of your first pet, make of your first car, and high school mascot can all be 'Dingleberry'. They really don't care, and in a way you're setting up a second, even more secure password.",
"Because the simple answer is that there are two layers of cyber security, theres passwords that computers can guess, and passwords that people can guess. The main password is one that should be safe from both a computer AND a person guessing it, so you want it to be more complex than \"abcde12345\". (A people easy to guess password), and you want some numbers/special characters to make it hard for a computer to guess. For example \"4Bcd3!2*$%\" is hard for a computer to guess. A security question does not grant immediate/direct access to the account, so there's no point in having a computer guess it, because even if you had a program to guess the security question, you would need several additional programs to use this Information in any useful way. TL;DR since the security question doesnt provide direct access to the account, it doesnt have to be as complicated as the main password"
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ee3tiz | Why are the separate detergents for front-load and top-load washing machines? | Technology | explainlikeimfive | {
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"text": [
"The two different types of machines use different amounts of water. So, the detergent needs to be tuned for the expected water/detergent ratio in order to work optimally.",
"As my grandma said: the detergent for the top loaders goes directly on the clothes so it can’t be strong enough to stain or discolour clothes if it doesn’t get absorbed in the water quickly enough. Front loaders mix the detergent with water before adding it to the clothes, so can be stronger. This is also why you generally need to be careful using front loader detergent for hand washing or spot stain removal.",
"I remember when I got my first front loader several years ago (a High Efficiency one) I was confused by the detergent requirements. I googled it and read up what others were saying. I came across a post by someone who was looking for 'HE' rated detergent but couldn't find it anywhere. So they called the manufacturer and eventually was told something like, it's all the same just different quantities. Use whatever you like but just use a little of it. I've followed that advice since and never had any issues."
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ee3uwk | How do telescope long exposures work, considering earth rotation and movement? | I really like Subreddits like r/space and they often post very long exposed photos of distant galaxies. Sometimes longer than 24 hours. But how can I do such a long exposure when the Earth is obviously moving? Isn't the change from night to daylight a problem here as well? | Technology | explainlikeimfive | {
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"Equatorial mounts are used, which are devices that once aligned with the north or south celestial pole (depending on location), will move with the rotation of the Earth so things don’t appear to move. When people say they did a 24 hour exposure, it is often not a single 24 hour exposure, but rather a bunch of smaller exposures, often done on different nights. These smaller exposures are aligned and stacked, to reduce noise. For example, 1440 1 minute exposures would be equivalent to a 24 hour exposure. The reason why this is done is for mainly two reasons. The first one being that like you said, the sun would interfere with the capturing of the image and the object would also likely be no longer visible as it goes below the horizon. Planes and satellites also cause trails in the pictures, so if we expose for too long then you might only see satellite or plane trails (especially with Star Link). The second reason is that as you open a camera shutter and let the sensor absorb light, the sensor will generate heat. Too much heat and the image will be super noisy, and the sensor could also be damaged. A lot of people use specialised cooled cameras with fans, but they’re expensive and you still won’t be able to take a single 24 hr exposure. If you’re interested in astrophotography, I suggest checking out r/askastrophotography and r/telescopes, both subs of which have friendly people who are willing to answer all your questions. Be warned though that you’ll need a big wallet; a setup can cost thousands of dollars. :)"
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ee5lem | What is it about low budget film footage that allows me to immediately recognize that it’s low budget? | I started watching I Am Alone, and aside from the purposeful “found footage” shots, it was clear in an interview scene that took place in an isolated room that this was a low budget film. The video and audio seemed clear, and plenty of high budget films have interview scenes like that. I assume that scenes like that don’t take any fancy camera work to shoot. So how did I just *know* this was a low budget film? | Technology | explainlikeimfive | {
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"Its almost always the lighting. With decent enough equipment and a moderately skilled camera man you can get good shots in most environments. Lighting is difficult and is both an art and a science and its not only about the equipment and technician. Very small changes can have massive effects and getting the lighting just perfect is something integral to a film that doesn't just look natural, but better than real.",
"Lighting and set design. Low budget tries to find locations that suit the scene, higher budget production builds their own from scratch if need to be. When you have a storyboard in low budget film, you need to change it as you go as you are practically limited how you can set up camera, lighting, how much can you change the set. You also have stricter schedule where you film a full scene in a day. Higher budget takes their time and focuses on details much more. \"Mise en scene\" is much less thought out in low budget and often out of your control: you shoot what you can use and you use what you have shot. No retakes, no redos, it has to be done, right now, right here. But by far the biggest visual difference is caused by lighting. No doubt about that. Bigger budget films lighting crew can be the size of your whole crew, including catering in a low budget film... You also will have cheaper cameras with less stellar optics and sensors. Although modern equipment is much, MUCH less restricting there is a difference between large and small lenses. Also the operators and director of photography are just that much better, in low budget you may not even have a real DOP but it can be the director or main camera operator that doubles as one. When you try to handle many seats in a project that absolutely does not have time and/or money to waste, things happen fast, everything is a compromise and \"middle ground\" options are chosen, true and tested, safe. You end up with less interesting camera angles that are technically safe, you have at least some footage in the edit that you can use. If you failed creating something usable by risking it on experimental camera angles: your whole project sinks if that is a pivotal scene. Having a real DOP who has real authority, they are one of the few people in the crew that can say \"no\" to the director but in the end make the movie tell the story right, subtle changes in framing, composition, mise en scene that is thought out months in advance in a well detailed storyboard that the production uses faithfully.. small things make a lot of difference. But still, it is the lighting that usually shows the budget..."
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ee8fux | Why are some cell services better than others even when the towers are in the same area? | Wondering why some provider service seems to be better than others even though the providers have towers located in the same spot? | Technology | explainlikeimfive | {
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"Each cell carrier in the US uses their own specific set of frequencies. Higher frequencies don't penetrate solid objects as well but they can transmit data faster. & #x200B; This is why if you have a wireless router at home with both 2.5 GHZ mode and 5 GHZ mode, the 2.5 GHZ mode is slower but has better coverage through-out your house whereas the 5 GHZ mode is faster but doesn't reach as far.",
"It can be due to the frequency that they operate in and/or the number of other users in your area with the same provider.",
"Can be a large number of reasons for this. They might not all have antenna on any given tower or the tower might be close to loading capacity and a certain carrier might be late tit he game trying to get space. They may not be able to negotiate a favorable lease on that site. As far as areas where they both have towers in similar areas geographic features can create coverage shadows in some spots from one site location and not another. The different providers may also be using different types of antenna, Omni vs uni, etc. Those antenna may be located on different legs of the towers or facing different directions. Any of these factors could come in to play."
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eea8gt | How is Kubernetes different from container platforms such as Docker? | Technology | explainlikeimfive | {
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"Kubernetes is what is called an \"orchestrator\". It manages Docker containers for you. If a container gets killed, it gets replaced. For example. Also scaling (launching multiple containers to meet demand), security (managing secrets within a container) and networking (make sure containers can access other containers) are part of the features. Be sure to check out other orchestrators as well. I always compare Kubernetes to a well equipped truck. You don't always need a truck, a motorcycle might be enough.",
"Check this youtube video it explains it really well in a simple way: URL_0",
"I'm not a expert, but Kubernetes is like the conductor and the Docker containers and the like are like the musicians on stage. Kubetenetes keeps them all working together properly.",
"Kubernetes is a container orchestration system where docker is the container itself. So I build an app, dockerize it, then you could just run that docker container without kubernetes. When you use kubernetes it gives you a lot of operational and production tools such as I want to run this many containers on these instances and lots more complex rules for scaling etc.",
"Kubernetes is the automation that would configure, run, and manage the life of your Docker containers. The most fundamental problem it solves is so that you don't have to log in to servers and run docker commands to manage your running container programs yourself."
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eec5cb | Why old movies look like they are accelerated? | Technology | explainlikeimfive | {
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"They actually were on a big tape film, the rolls used to roll. Up and therefore the radius /circumference of the movie roll got bigger and faster. They could not slow it down perfectly and didn't want it too slow at the start. That's what i was told."
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eef5z1 | How was Bill Gates “Windows” OS different from Mac’s and Linux/Unix OS and what made it become so successful? | Technology | explainlikeimfive | {
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"You have the order a bit backwards. The real benefit of DOS, and later windows, was from hardware, not the OS (at least in how it grew to start). DOS (and then windows) ran on any IBM compatible PCs, which were the standard and produced in huge quantities. Macs only worked on specific Mac-made hardware, and were relegated to a niche market at best. The sheer volume of IBM compatabile PCs was huge-- so everyone wrote programs for Dos and Windows, and they are pretty user friendly to use, and well, everything worked on it, and everything was made for it. It dominated the market. Linux/Unix systems have for the most part once we start the DOS/Windows eras, were relegated to specific, generally specially trained IT uses, not for the general user.",
"It could be argued that the main reason why Windows was so successful had little to do with the technical differences to its alternatives but everything with the way it was sold and marketed. The origins of modern Windows go all the way back to DOS, which Bill gates did not actually own when he sold it to IBM as the OS to be shipped with their new \"Personal Computer\". DOS itself was not too different from its competitors and relatives in those days, which were all similar text based interfaces with names like CP/M. The real magic came from the fact that IBM's PC concept was a runaway success much more so than anyone at IBM or Microsoft could have hoped for. The fact that the PC was built not from IBM's own parts and proprietary standards, but mostly from off the shelf parts open standards and stuff that could be relatively easily reverse engineered, meant that companies could build their own version of the machines that worked just the same. Any many companies did and still do so today. what was once advertised as a computer that was 'compatible' to IBM's PC is today just a PC or even just a computer. The format utterly dominated the marketed and everyone was making them and selling them and buying them. However to have computer that really worked like IBM's PC, you needed not just hardware that worked the same, but also an OS that did so. That is where Microsoft came in. While some companies tried to do it without MS and build their own DOS without paying them, this had some technical difficulties and Microsoft's lawyers as obstacles. Microsoft DOS was the OS that everyone expected Computers to run and that everyone wrote software for especially in a business context. (Other Home Computers managed to stay on for a while in non office settings, kept aloft by games and other non-business uses). Meanwhile in the distant past of 1968 a person called Douglas Engelbart (who may have been a lost time traveler) put on a demo at Xerox to demonstrate how he thought computers could be used. He presented such futuristic ideas like a 'computer mouse' to use a graphical user interface with 'Windows' and lots of other innovative ideas that someone using Wikipedia or Skype today would find extremely familiar. Those ideas were largely ignored for a long while. In the words of Marty McFly: > I guess you guys aren't ready for that, yet. But your kids are gonna love it. By the early 80s Engelbart's ideas finally started to become reality. Apple released their first computer with a graphical user interface based on these ideas and it was very well received. It should be noted that that MacOS was not the same OS used on Apple computers today. It was its own thing unrelated to anything else around today. In any case the people at Microsoft saw what the people at Apple had seen and wanted in on it. However they couldn't just build a completely new OS, so they released \"Windows\" as an add-on to DOS which ran a program inside DOS rather than its own OS. From a user point of view it looked and worked really similar to the way Apple's MacOS worked and many accused them of plagiarism if they didn't know about Engelbart's demo in 1968. This idea caught on and similar GUIs were made fro just about any Computer out on the market that could support it. Even the C64 got its own \"windows style\" GUI OS with GEOS. The UNIX community built a number of different variants, but eventually X-Windows as it is still used today became the add-on that would give a UNIX OS a GUI. It is still used today on Linux and*NIX machines, but Android and the modern Apple OS (which technically belong in this group) use their own alternatives. Back in the late 80s Microsoft realized that the future of a bolted on graphical user interface to their old text-based DOS had a limited future. It sold well enough, but there was only so much you could do with a house whose foundations were built on sand. So they got together with IBM the inventors and makers of the PC to make a new OS. IBM made a number of operating system over the years and they made the hardware it was to run on so that seemed like a good fit. The partnership ended in tears. And IBM ended up making OS/2 out of what was left of it, while Microsoft made not one but two different OSs. One was Microsoft NT meant for the business and they started numbering it from 3.1 on because that is where their bolted on Windows running on DOS was version wise at the time. The other would eventually become Windows 95 the successor to DOS for the home computer market. IBM's OS/2 was arguably the better OS but Microsoft had the better marketeers and the advantage of being able to convince other hardware makers to include their products which was much harder to for IBM who would have to convince its competitors in the computer making business. In any case the Windows 95 and later Windows 98 were a hit. They were not as good as some of their competitors and had many flaws, but they were everywhere. And since they were everywhere business made software for it and since it was the product that everyone made software for they came to dominate the market even more. Eventually Microsoft ended up extending the Windows 95/98/98SE lineage to Windows ME, where it ended in a fiery crash of epic failure. The decided to scrap the whole thing and looked at their Windows NT line of products which had been running in parallel in the business world unbeknownst to home PC users all the while. Windows NT5 was released as Windows 2000 and was slightly more Succesfull than Windows ME. A few years later its successor was released as Windows XP (With a server variant called Windows 2003) and it was an extreme success. All subsequent version of windows built on that. Meanwhile in world of Apple computer things weren't going as well. Steve Jobs had left the company and it was failing all around. Jobs meanwhile had gotten involved with something called NextStep, which was an Os from the *NIX family of OSs and based on BSD (you may think of it as the Linux's Linux in terms of obscurity and technical superiority). That computer system had the honor of being the OS that the first web-server and web-browser had been built on back in 1990. It was cool and better than anything else and nobody had ever heard of it. Steve Jobs got involved with the system after he left Apple (with a brief stint at some place called Pixar that wanted to make cartoons with computers if you can believe it). Eventually Apple saw that their MacOS had no future and if they didn't think of something fast neither would their company. so the bought NextStep along with Steve Jobs. in the late 90s. the continued to develop the OS and eventually replaced their old OS with something they called MacOSX which had no relation to the old stuff and was secretly NextStep under the hood. They build their own GUI component though as the X-Windows stuff everyone else in the *NIX field was using wasn't quite what they wanted. It is what every Apple Product sues today. Finally Google came into existence and got extremely rich by selling everyone your data and they decided to make their own smartphones. They started out based on Linux but also threw away the x-windows system and instead created what is now known as android. Today generally the functionality from a user perspective is pretty much the same across the board. What difference their are, are less in capabilities but in choices of the manufacturer, which is why Open source based systems can and dow look and work like anything else on the market. Underneath it all there are some major difference although Linux/MacOS/Android are all related and share many technical aspects due to their common heritage. Microsoft's windows on the other hand is its own thing. It copies some superficial parts from other systems but its underlying engine is somewhat unique. One thing that stands out with Windows is that in many ways it kept is backward capabilities to all the way back to the earliest DOS release. (Try creating a file simply named \"prn\" on your windows computer some time as an example of a rule kept from the days when DOS didn't even know what folders where.) However it can easily be argued that none of the technical stuff really mattered in the success of the system as it was Microsoft's ability to leverage their market position of being bundled with the first PC into keeping the dominance of the market ever since. Of course as stuff like Windows Me or Vista or 8 have shown, they still had to create a good product in order to succeed and couldn't just shovel out any crap they wanted, but many OS that were in some ways or other better were released over the years and decades that failed to win against Windows."
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eef6j6 | How is Choreography transcribed? | With things like ballets and musicals, how does the choreographer write down what the dancers should do? Is there a standard notation? Is it sketched? Before recording was possible, how did the producers know how to make Swan Lake the same way each time? | Technology | explainlikeimfive | {
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"Some of the steps have names... like in ballet when they do a squat, it's called a plie. When you stand on one foot it's called an arabesque. There was also 5 positions which feet and arms differ. So a choreographer could say, 3rd position, plie to arabesque, sashay to right 4 counts... In tap, theres steps like a buffalo (leap to right side, shuffle left foot, then hop while lifting right leg in front of left) I was in dance when I was in 4th through 10th grade and I remember my instructor would write down the steps or would make up a way to describe the move. Like the waiter, she told use to move our arms like we had a serving tray. I'm sure it gets more complicated and detailed for ballets like swan lake, but this is what I remember from my experience"
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eeffqy | Why is NASA looking to private companies to learn how to get astronauts into space when they already know how to do it on their own? | Technology | explainlikeimfive | {
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"A couple reasons. 1. Right now, virtually everything sent into space uses Russian rocket motors. The Soviets built very, very good rocket motors. The only way to get astronauts into space currently is also via Russia. This is problematic since it means access to space is based on cooperation of the Russians. 2. On top of this, the NASA budget has been greatly reduced. As a result, the motto is do more with less. 3. The private sector is promising that they can solve problem 1 on a shoestring budget, which would allow NASA to stay in the space game. So, NASA is throwing money at private sector actors to build them a rocket betting that it will be cheaper than doing it themselves. The companies are betting that they will make a rocket that they can sell to NASA and other people who want to put stuff in orbit over and over, but gladly take the government money to fund their development costs.",
"They know THEIR way to get astronauts into space. But NASA scientists realize that just because they can do something, doesn't mean someone else can't do it more efficiently",
"It's not a matter of knowing how. It's a matter of cost, advancement via private investment, and creating multiple parallel development that the tax payers aren't directly responsible for or dependant on congress"
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eeg0gp | Why don’t we have massive industries that desalinate saltwater? | Technology | explainlikeimfive | {
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"Because it costs huge amounts of energy(Money) to desalinate water and there are large enough reserves of water around the world that that it's so cheap you can just ship it to where it's needed. Here we've granted several water bottling companies rights to 180 million liters/year for basically free. It costs around $2000usd per million liters to desalinate water. Or $360,0000 for that free water. $2K isn't really a lot. But it's still more. So...Yeah, freshwater isn't rare enough or valuable enough, there are a lot of desalinization plants around the world in some specific places where it's viable. But on a global scale? Not yet.",
"It's still expensive as shit is the simple answer. Same reason why solar power (despite how far it has come) is still unfeasible for large scale operations.",
"Freshwater is precious because it takes energy to create. It takes an extraordinary amount of energy that cannot be recaptured to turn saltwater into freshwater. URL_0 > It takes most reverse osmosis plants about three to 10 kilowatt-hours of energy to produce one cubic meter of freshwater from seawater. That's 264 gallons of water; a gallon of gasoline contains roughly 33 kilowatt hours. That means each gallon of gasoline can make roughly 970 gallons of water URL_1 > Estimates vary, but, on average, each person uses about 80-100 gallons of water per day, for indoor home uses. That means to provide water for the 39,000,000 people of California through desalinated sea water you need to provide the energy equivalent of 40,000 gallons of gas per day."
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eek90j | How do game developers release their titles with the latest graphics, despite working on it for years? | Technology | explainlikeimfive | {
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"Game Dev here, when making a game we use placeholders while we do all the mechanics of a game, then later we'll go through and update the models/animation to match current standards. It's not as much of a problem nowadays though because most visual features in an engine are pre-built so any changes that you need can be made fairly easily, at least compared to how things were before. Another point especially true in AAA games, they often have godlike systems that can run demos that your favorite twitch streamer could never dream of, I've never worked in an AAA environment but friends say that they often work with what they can (often meaning AMAZING visuals), then they dumb it down to what the current standard of gaming PC's can handle, which I've been told is why teasers and trailers of gameplay often look super amazing compared to the actual release.",
"Some games go back to the drawing board. Duke Nukem Forever was notorious for going through multiple game engines as the game was delayed for years and years. Other games just push forward and keep what they have, but update the graphics/engine incrementally. Also, even if you update the graphics, you can still keep a lot of your gameplay and story, so you're not going all the way back to zero"
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eekrdf | Why do consoles work fine with TV's but using your PC on a TV with hdmi has in output delay making gaming dreadful? | Technology | explainlikeimfive | {
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"Many people use their PCs with a TV, with an HDMI cable, to play video games (myself included) and experience no I/O delay. Either something is wrong with your setup, or you are experiencing problems unrelated to the setup."
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eelehb | how do bluetooth earbuds keep the sound perfectly synchronised between the left and right bud ? | Technology | explainlikeimfive | {
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"Each earbud is basically a small signal receiver. Signal from music player is send simultaneousely to both of them, but some things (stereo sound) are different. You don't have to synchronize them too much, because microchips in each earbud interpret signal so fast, that you don't even notice it...",
"I dont know how earbuds specifically work but you can actually hold the received signal in the chip and synchronize it there, but do it quickly enough that the listener wouldnt notice the slight pause in the beginning, yet slow enough to gather enough of a signal to play it perfectly as it comes through, even if there are some interruptions on one half of the signal"
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eelojc | When Windows XP froze and you dragged the window around, why did it make a bunch of copies of the window or error popup? | Technology | explainlikeimfive | {
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"Windows only redraws what it has to. Unlike a game, the entire screen is NOT refreshed every frame. This means portions are only redrawn when necessary, like when a window hides part of another application or when displaying video. Each window is responsible for drawing itself. The image of the window you’re dragging is drawn on top of whatever froze, as it should. But when Windows asks the frozen application to redraw, it’s frozen so it can’t respond to that request. Thus, it can’t redraw the part that was hidden and so the window you’re dragging is leaving a mess. [Edit] As /u/arcosapphire pointed out below, I'd like to add that Windows ~~7~~ Vista changed how drawing works from Windows XP. This doesn't happen anymore because Windows is constantly refreshing the last known image, even if an application is frozen and can't respond to redraw requests. Windows Vista and up does, in fact, redraw the whole screen every frame -- preventing the \"drag mess\" -- but only *updates* necessary parts as Windows XP did (which, from the perspective of an ordinary user, isn't much different from updating the whole thing at once). From a practical perspective, Windows XP did what it did the *way* it did for performance reasons. Windows Vista completely changed the underlying method of how it draws the screen. A super brief ELIALittleOlder since this post is already long: it went from DirectDraw \"bit block transfer\"s to Direct3D and textures.",
"Also does this graphical effect have a name?",
"This is because Windows XP used a \"stack\" based window manager as opposed to a modern \"compositing\" based window manager now used in all major operating systems. When a window becomes unresponsive in a stack based window manager, it cannot draw new frames. So if you drag another window over it, ghosts of the top window will appear over the window below. In Windows XP it was common for the entire desktop to become unresponsive except for the error dialog that pops up telling you something is wrong. When you drag the dialog around and have ghost copies of it appear all over the screen, essentially what is happening is the window manager is supposed to redraw what was below the dialog now that you're moving it out of the way, but it can't, so ghosts of the last frame linger because the window manager has nothing else to draw. Modern compositing window managers avoid this problem by buffering the last paint of each window in memory. So if a window freezes, it will always display its last frame regardless of what you drag over it because it has a copy of its last frame in memory and can always redisplay it when you drag something out of the way. Compositing is also what makes it possible to have drop shadows, window scaling, and 3d window management effects. If you're feeling nostalgic for stack based window manager ghosting, play around with another web-based simulator here: URL_0",
"The first time I took mushrooms I kept seeing this happen to people and moving things in real life. I could not for the life of me figure out how to explain what everything looked like to the people around me.",
"URL_0 Doesn't answer the question, but the band Ok Go used this effect in one of their music videos, and it's remarkable.",
"One of the processes of windows is to redraw the background of the screen when you move a window. That process wasn't running. So the background behind the previous windows was not redrawn.",
"each window (including the desktop) has its own content that has to be redrawn as stuff moves in front of it. it's not a priority when a program or OS is struggling with something else, so the area that used to be covered by the window you're dragging doesn't get updated",
"Real question is, why was it so fun?",
"I don’t know if this is going to be removed for not being useful but thanks for my new favourite website.",
"In Windows XP, a \"window\" was more like a region of the screen you were given control of; initially it would consist of whatever had previously been there (a portion of the desktop, another window etc) and most applications would use it to \"draw\" a familiar window-like interface. For performance reasons, this drawing did not take place constantly, but, rather, \"on demand\"—whenever a part of that window, which had previously been obscured by something else (e.g. an error message) would be \"revealed\", the owner of the window was asked to redraw the revealed region (most lazy programmers would redraw the whole thing anyway). However, this only worked well as long as the application owning the window was responsive and able to redraw things on demand; when it couldn't, as I said above, the \"default\" state was \"whatever was there before\", so you'd get a fragment of the error message that was \"stuck\". Every time the application failed to redraw, you'd get another stuck fragment, and so on. The last bit of relevant information would be that the desktop itself is a window of sorts and it, too, can fail to redraw, leading to the described effect."
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een4dt | Why do computers get slower the longer you have them even if they aren’t damaged? | Technology | explainlikeimfive | {
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"Marginally they do get slower as you install more programs that want to keep running and as temp files and such build up. But that sort of slow down is minor. The feeling you get that your system, which used to be super speedy, is now chugging along is more that over time the software released keeps asking more from the hardware. Windows gets more features, games want more cycles for logics, Word needs a GPU now so it can have pretty toolbars, etc. So really the machine is just as fast as it was, the programs just become more demanding until it can no longer keep up. Of course, sometimes you will have just installed terrible stuff that's eating all your processing but that's more of a virus / malware situation than normal \"aging\".",
"Your computer is a weightlifter. The software is the weights. Dude's just as strong, but the software keeps getting heavier.",
"There can be a variety of reasons for this. The first one that comes to mind is updates. As Windows receives patching throughout its life cycle, the operating system gains more bells and whistles and features, but the hardware hasn't changed at all. This also doesn't take into account any applications the user may have installed that have set themselves to begin running on startup. So the PC is now trying to do more with the same amount of resources. Additionally, some of these updates may cause issues with hardware not knowing how to handle the latest major service pack/update/or whatever. These issues can usually be resolved via firmware or BIOS updates, but most people don't know or take the time to do these, or in some cases, the system's motherboard is no longer supported by the manufacturer and as such no update exists to address these issues. Another reason may be that many people never clean or service their systems physically- a computer that is a few years old may get a lot of dust buildup- this is particularly exacerbated in households with smokers or pets, where tar and animal hair can further clog intakes and cooling systems. As the system loses the ability to cool itself, it resorts to thermal throttling- decreasing a processor's power in an effort to produce less heat but also generating less horsepower. Lastly, file clutter on a hard drive may be a contributing factor. This is less true since the advent of the SSD has become more common, but there are still many hard drives in service. Hard drives store data sequentially- in the order that files are written to the drive. When a file is deleted, a blank space is basically created where that data used to reside (well, technically, that data just becomes a rewritable sector, the data isn't truly \"deleted\" until something takes its place. The hard drive, however, continues to write sequentially. This creates gaps over time and the system has to spend more time searching the drive to assemble all the fragments of a file that make up a program or whatever. Reassembling all these fragments and getting rid of those spaces is what defragmentation does, and it makes it easier for a hard drive to find the files being requested. Here's a better way to visualize this: Imagine, if you will, that the hard drive is like a jigsaw puzzle, and the puzzled is assembled from left to right, bottom to top. A program is a given cluster of puzzle pieces. So you get halfway through the puzzle and decide you don't want a program you installed at the beginning anymore. So those pieces stop existing and now you install a new program. Well, half of that program takes up the space where the original program was, and the rest of it winds up where you left off in puzzle assembly. So in order for the PC to load the program into RAM when it's launched, the hard drive now has to go to the start of the puzzle as well as the end of the puzzle in order to find all the pieces necessary. Defragging a drive basically reassembles all the puzzle pieces so they're all in order again.",
"They don't, your expectations change and the software that runs on them changes. I have worked on massive server systems, they run basically the same at year 7-8 as they did in year 1. The difference is if there was a burst in technology during that time your system is in technology freeze. You will still get the same performance that was awesome when you implemented it but now looks like a Yugo compared to a Ferrari to the newest system. This actually happens a lot less than you might think. There are an awful lot of critical systems that are still running on technology freeze that happened back in the 90s. Technology freeze is a term not everyone is going to be familiar with. When you are designing a complex engineering project (spacecraft, aircraft carriers, etc) there is going to be considerable time between deciding what you are going to use and when the ship sails or plane flies. During the rest of the engineering, QA, UAT, phases etc there will be advances in technology. To you this doesn't exist, you are in technology freeze. Changing it while in QA will add risk of failure somewhere else in the system."
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eeqfq5 | what (if anything) do corporations gain from these robot calls that leave voicemails on my phone in Chinese? And how? | Technology | explainlikeimfive | {
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"You sort of answered your own question. They send them out in mass so they don't know what language you speak."
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eeqh0w | What is 'parsing' in computer syntax analysis? | Technology | explainlikeimfive | {
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"Ifyoureadthisstreamoflettersyoucanprobablystillunderstandwhatiamsaying. Your brain is parsing that long string of letters. It breaks it apart in to words, then as it assigns meaning to the words to form complete sentences. Parsing in computer syntax analysis works much the same way. You have some data that the computer can't really use in its current form: takes it in using some specified method, and assigns some meaning or arranges the data in to some structure it can utilize.",
"It means to take some data that is stored in a file in some predefined format and read it in to memory in a structured way.",
"Parsing is the process whereby a computer tries to construct a functional/machine-usable representation of the data in a (text)file. If we’re talking about programming, parsing is the second step before compilation, after lexing, which is the first step. In short, this is what happens when you write and compile a program: 1. you write source code in a text file 2. the lexer will analyse the file to figure out which keywords are used at which positions, where structures are declared and by which name, and where variables are declared and instantiated 3. the parser will read the output from the lexer and create a functional model of the program 4. the compiler converts the functional model into an executable binary (More complex stuff such as linting, statical analysis, etc may also occur, but I’ve omitted those for clarity) So a parser is simply a tool which transforms data into a machine-usable format. In this case so it can be turned into an executable, but it could also be used to convert data from a file into application-specific objects so a program can perform operations on it."
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eerbnu | How do we have so much metal? Anything you can think of from kitchen appliances to cars, tons upon tons of metals are being used constantly. Surely the source is finite, will we not run into a crisis eventually just like our fears with oil? | Something that has only occured to me recently, we seem to always have metal with no talks on running out at an estimated year or distant future. So.. what are we looking at here? Do we have hundreds of years left of this particular resource? Mainly speaking of Iron and Aluminium for example. Edit: Responses are coming in rather quickly and I haven't the time to respond to all replies so for that, I am sorry though I am still reading them and giving them an upvovte! | Technology | explainlikeimfive | {
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"Aluminium and Iron together make up 13.1% of the Earth's crust: [ URL_0 ]( URL_1 ) That's an enormous about of metals in ground.",
"Aluminum and iron make up a pretty large percentage of the Earth's crust. It may become increasingly expensive to extract, but we'll probably never run out, or at least not on any meaningful timescale. Like, it might take a million years to use up all the available iron, and by then we could be electronic pulses living in laser forts in space or something.",
"The great thing about metal. You can easily melt it down and remove additives and impurities and reuse it."
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eey2pv | Does the "Reset Factory Setting" option on many devices do anything aside from deleting all your files and cancelling any changes you made? | Technology | explainlikeimfive | {
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"Usually this does what it says: resets to factory settings. It doesn't just delete your stuff. It's brand new again, at least from a software point of view. If it's a connected device, like a phone, it might need to update, since the factory software could be years old."
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eey3q3 | Layer 2 Tunneling Protocol | In networking tunneling is required to transport private data on public networks like internet . Then What is The need for Layer2 tunneling protocols like L2TP ? If required where is it used ? | Technology | explainlikeimfive | {
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"Well let me just put on my tinfoil hat and say don't use L2TP because it's been weakened deliberately by the NSA. It's the Microsoft standard point to point VPN. Meaning it will encrypt all your traffic between 2 points effectively created a direct network. This is commonly known as a VPN or virtual private network. In my opinion the best protocol is OpenVPN. It's a highly secure open source standard. It's free to use and just requires a simple installation. It can be a bit more complicated to configure properly though."
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ef0wg8 | Why are contact-less credit cards a good idea? Doesn't it just make it less safer and easy to be used if stolen? | Technology | explainlikeimfive | {
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"The transaction amounts are limited (depending on the country the limit is different) so the risk is very low. The card can only be used contactlessly around 5 times before it needs to be inserted and used with chip Banks have fraud monitoring where they will decline transactions if they think they’re not made by you or are unusual / too close together. You can very easily block your card and it won’t work if someone has stolen it (it will beep but won’t be approved)",
"The rage of contactless cards and readers is very low. Basically a criminal would have to slap your pocket/purse with a CC terminal to scan a card in your wallet. Of course that will probably result in charge backs and that criminal being banned from that credit card processor. Likewise, the authentication protocol is similar to contact chips: the data read by the reader isn't sufficient to create a clone that can be used for anything but the original transaction. And just like chips/stripes, PIN verification can be used, and banks will be monitoring transactions to highlight/block what they think may be fraudulent."
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ef1dra | How is a game converted to a rom for emulation purposes? | I'll just ask about Dolphin's Game Cube since I use it. How does the rom process work in allowing a GC game to be played on Android? Does the process have anything to do with why there are only a limited number of roms? | Technology | explainlikeimfive | {
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"A rom is just a copy of the media. In case of GC it's a copy of the data stored on the CD. Some roms are encrypted, like on the 3ds and you need to decrypt them before use on a device. They're called ROMs because originally they were the *dumps* of Read Only Memory chips found in cartridges and arcade cabinets. Today however, they are more akin to directory structures found when browsing a PC/Mac rather than binary dumps of a single chip. If you're emulating the GC for example, it's more appropriate to call the games you're emulating \"images\" - \"disc images\".",
"I have a potato (a game) , I know how to eat this potato (I'm the console). You have no idea what a potato is (You're the PC). To you it's just a weird object. You take this weird object as is without understanding it (ROM). Then you watch me how I'm eating it, and you replicate the exact steps I'm doing (emulator) to eat the potato . Now you know how to eat a potato. The reason there's a limited number of potatoes you can eat, is because not all potatoes are the same. Some have a complex way of eating them , so it's hard for you to replicate the eating process. Unless you understand exactly how I'm eating those complex potatoes and replicate it yourself.",
"It depends on the platform. Typically in older systems you would have some sort of interface to the cartridge that could pull address lines up and read data lines in sequence transferring it back to whatever you’re going to store the ROM on. For a lot of the DVD based consoles they would often need custom firmwares for certain PC DVD drives or, if you could get access to run arbitrary code, you dump the game over a serial connection or network. For the GameCube it usually involved exploiting another game (i.e. Phantasy Star Online) to run a dumper that would send the contents of a GameCube mini DVD over the network to a host computer. These days it’s much easier because you can use a DVD dump tool from the Wii’s Homebrew Channel."
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ef1q2e | Does colorblindness affect the functionality of old-school 3D glasses? | Technology | explainlikeimfive | {
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"It’s not seeing in red or blue that makes the glasses work. It’s the red or blue light being stopped by the lenses before it ever hits the eye. This splits the combined image into two separate images.",
"Colourblindedness does not affect how red-blue 3D glasses work. The red-blue aspect is just to trick your brain into resolving two different images.",
"No. The lenses filter the light before it reaches your eye to produce two seperate images in each eye. So the lenses are still doing their job, still producing 2 seperate images. You inability to see a certain color does not change how the lenses work. There are still 2 seperate images after the lens. You will still see 3D."
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efcnp5 | How do flushless urinals work? | Technology | explainlikeimfive | {
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"They have a cartridge in them with a thick fluid that floats on water (and urine). When you pee into the toilet, your urine flows into the chamber and the thick fluid floats on top of it and forms a seal that mostly keeps the smell from getting too bad. As more ursine enters the chamber it displaces the urine/water that’s in there and it flows into the sewer line. In that way it’s just like the the P trap in a conventional toilet. There’s a plug of urine/water that keeps sewer gasses from coming up with a secondary plug of sealant fluid floating on top of that. As often as possible, such as every evening, someone maintaining the bathroom should pour clean water into the urinal to flush out the mostly-urine in the chamber and replace it with water (still covered by the thick fluid). Over time, the thick fluid gets depleted and you can swap the cartridge out for a new one. If you don’t, eventually the urinal will get smelly."
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efd4yi | How exactly do Intel and AMD improve their CPUs ever year to become more powerful, faster, efficient? | Technology | explainlikeimfive | {
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"Since you already have a technical answer, the other viewpoint is: By spending [over 13 billion a year in R & D.]( URL_0 ) Why? It’s not driven by consumer demand. The goal is to force competitors to also spend huge amounts on R & D (hopefully money they don’t have) or risk falling a generation of chip design behind.",
"Because there is a long pipeline of technologies in the research labs and equipment labs of many many firms involved in semiconductor manufacturing. Modern CPUs etc represent the apex of human mass manufacturing technology. The infrastructure (equipment, factories, test etc) are in the 10's of BILLIONS of dollars located around the world. The supply chain is long and tortuous with many ICs travelling thousands of miles in the manufacturing process (Japan, Europe, Taiwan, US etc etc for die, fab, test, packaging assy ...) At the end of the day, there is no real economic feasibility making a hugely powerful CPU that yields 1 out of a thousand in a factory. The supply chain commits billions of dollars annually in capital equipment and many hundreds of millions more in research and development in material sciences, computing, physics, robotics, sensors, laser development, chemistry.... involving hundreds if not thousands of PhDs working on various areas. And this is cutting edge - so there is no such thing as \"start here and we'll end here next year\", many areas and approaches are tried and abandoned. Any technology introduced this year probably spent a decade prior in research and development, equipment design, testing with constant set backs and challenges. My guess is that a lot of people realize this (semiconductor design and mfg) isn't easy but I also believe that most people underestimate how complex this is by an order of magnitude or more.",
"Cpus are all about the size of the die. Each wafer is a certain size that they cut up into different dies. Making the wafer is what costs money so they make more money by getting more dies from a single wafer. So basically they could make one super powerful cpu that would take up the entire wafer but itd be super expensive and there could be difficulty cooling it. So at the end of the day it's about balancing the heat and the total size of the die. Making transistors smaller allows for smaller dies for the same given design. Making more efficient designs allows for more compute power for a given die size. Adding more cores allows for more processing power at the cost of more die size. So basically it's about balancing the die size, making the transistors smaller, and more efficient designs.",
"This might further confuse the issue but \"nanometer size\" is pretty much just a marketing exercise these days; it is *somewhat* useful for comparing products from the same manufacturer but means basically nothing across manufacturer lines as they can basically define what to measure in nanometers and just measure the smallest thing. An example of this is Intel's new (upcoming?) 10nm process. You'd think given AMD is using a 7nm process they'd have much more efficient and market leading designs...the number implies theyre 30% ahead, right? But in reality Intel made a really aggressive push with regard to transistor density (how closely together the transistors sit), and the result is a similar power/efficiency level in spite of the different marketing terms. Now, does someone else want to delve into TDP? 😋",
"I think a more direct way of answering your question is: It's not an easy feat to fabricate the hardware. A CPU is a complex mesh of little circuits which do little specific things, then have to talk to other little circuits which do more different little things. How fast or efficiently they do those little things, how many different little things they can do, how closely they can approximate other more different things they can do, and how fast they can talk to other bits of the cpu all matter to overall performance. The three main ways of boosting total performance are refining the little parts to do their specific job faster or better, to make things smaller so that the electrical pulses can move around faster, and to move little bits of the processor around so they sit closest to what they are relevant to. The ELI5 I would use is consider the electrical pulses like trucks moving cargo (data) between different parts of a supply chain. You can move warehouses around the city so theyre closer together (die layout changes), you can make the roads shorter by relocating sites (transistor/die shrinks), and you can upgrade your warehouses so you can get products more assembled so they need to be moved around less (architectural improvements).",
"It’s due to the ability of making things smaller and smaller. The smaller the processors, the more you can fit into the given space. Now your computing is faster. Now you develop a way to make everything 2% smaller. Now you can fit even more processors into the same space. If you’re always working on doing everything as big or fast as possible you’ll never keep up with manufacturing progress. By the time you design and construct the biggest and fastest it will already be obsolete due to nominal advancements.",
"When you're fabricating CPUs, you take a big wafer and make as many of them at a time as you can fit. As the process isn't 100% accurate, you design in a modular way, expecting some failures, then you then test all the CPUs made and the ones that run best are \"binned\" as the top tier that you sell, the less good ones are binned into different tiers, down to the ones that don't work well enough to sell. When you first set up a new processor line, you are likely to get a high number of processors in the lower bins and very few of the top tier. As you work out the bugs, you can up the number of high quality processors (to the point where you have to intentionally turn off parts of working chips to sell as lower quality parts). Making a single chip the size of a wafer would work, but would be very expensive and all but guarantee some bits wouldn't work. There is actually a startup trying to make an AI chip this way (Cerebas Systems Wafer Scale Engine) which seems like a good fit - AI workloads are hugely parallel so make a chip with a monstrously large number of cores and don't worry about the ones that fail. Basically the way you design a supercomputer, but with the interconnects on the chip itself (and smaller / less powerful cores)."
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effi5l | How do online services let me login with a password while claiming they dont know it? | Title basically, there are tons of online services, including games etc that claim they do not save any passwords nor can they look them up. But how can i log into them when they don't know my passwords or how does the server know that my password is the right one? | Technology | explainlikeimfive | {
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"They store *hashes* of your password. Basically, a hashing algorithm is a mathematical function that will always return the same output given the same input. So, if you were to input \"password\", the hash would always be something like \"kfd0aijffjfj0939jk0909f\" (I've just typed in random characters, but it's definitely not random). One of the properties of a result of a hash function is that it is *infeasible* for an attacker to reverse-engineer the hash and figure out what the original input was. There's a whole bunch of funky math that goes into it, but that's basically it. And it's due to a couple of properties of hash algorithms that I can go into more deeply if you would like. Hash algorithms are probably the major underpinning of *all* information security. Your computers use them, your phones use them, and servers use them (mostly. Sometimes a company will be very stupid and store your passwords in *fucking plaintext* (I'm looking at you, Facebook, you scummy piece of shit)).",
"When you type your password, it goes through a formula before the comparison happens. For example, suppose your password is **10** and the magic scrambling formula is **y=4x-7**. When you type in **x=10**, the online service sees the result of **y=33**. They just know to check for **y=33** to confirm a match. Can't you just reverse the formula to start at **y=33** and know that the user's password is **x=10** to begin with? Well, if the formula was truly as simple as **y=4x-7**, then yes. But these formulas are so complicated that it's not easy to \"apply the formula backwards\"."
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efkmbv | How to delete the "Disable ad-blocker" pop-up through inspector without deleting the entire page's contents? | Technology | explainlikeimfive | {
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"I recently found nano Adblock and nano defender and they seem to work without you doing anything, those are automatically blocked"
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efmx0f | Why does updating my video card driver fix issues that never existed before the update was available? | Say Nvidia releases a Geoforce update for my card, right? Say this update does nothing but add support for a game I don't even have. Now imagine that a game I was playing all day suddenly stopped booting up and started to give video errors, but the update fixed it. The update in question came out on the 10th, so in all actuality, why did my game work all day, then stop working, and now works again after I updated? | Technology | explainlikeimfive | {
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"*officially* it might only just add support for game *x*, but there will be dozens of bug fixes and tweaks in there too. You’ve been playing the game all day and thus the state has changed - new levels unlocked, new cut scenes played, new characters, etc. There will be known edge case bugs which the developers accept prior to release. There is an *insane* number of configuration combinations available on your PC and QA can’t possibly check them all."
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efn8l5 | In the 60s long before CGI, how did movies fade text and titles in and out of a background image? | Technology | explainlikeimfive | {
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"They literally physically cut and pasted frames of film together. They had physical film, so they could manipulate it in any arts/crafts way. They could paint it, stamp something on it, cut out a shape from one frame and paste it into another, etc."
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efvo7u | How does a phone know how to "fast charge" when using the official charger and how to "slow charge" when using a generic charger? | I have a Samsung phone and when I use the proper Samsung cable and plug piece it charges quickly however when I use a generic cable or plug piece it charges significantly slower. How does my phone recognise the difference, isn't electricity all the same? (insert Mr Incredible meme). | Technology | explainlikeimfive | {
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"text": [
"The phone asks for as much power as it can take, the power brick gives it as much power as it can give. Your official Samsung charging brick can output more power that most other charging bricks."
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efwv1s | Why do broadcasting video cameras in sports (e.g., football, soccer) show no rain from some angles, but from others you can see it's pouring down rain? | This was asked a few years ago, but the 4 comments responding amounted to 'raindrops are too small to see on video.' But when watching a football game in the rain, from some angles you can see that it's pouring. But for the vast majority of the game footage (even close-ups of players) you often can't see the rain at all. | Technology | explainlikeimfive | {
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"it's a result of using telephoto lenses and narrow aperture settings. they are zoomed way in most of the time which compresses the scene, and anything which is out of the plane of focus (which may be rather narrow) will basically just not be very visible. it's sort of like when you look outside through a screen window, if you're looking at an object outside you won't notice the wire mesh much.",
"This could be due to “focal length” and “depth of field”. Imagine someone with rain on their spectacles. The wearers eyes are focused on something beyond their spectacles, and so they don’t notice the drops much. Their eyes are focused on something far away, and not on the glass right in front of the eyes. In a bit more detail. The amount of light a camera lets in is controlled by “aperture”. This is basically an opening on the front of the lens and is measured in f-stops. It controls how much light enters the lens. Too much light and the image is over-exposed and looks really bright white in places where you should see detail. Some would say that image would be “blown out”. The opposite is also true; not enough light and the image is dark and black in places where there should be detail. Some would say this image is “crushed”. If a camera has a wide open aperture, it’s letting in loads of light. A side affect of wide open aperture is shallow “depth of field”. DOF means how much of what the camera is looking at is in focus between the very front of the lens, and things furthest away. Wide open apertures, such as f/1.8 mean that only a teeny section of the subject is in focus. Portrait photographers use f/1.8 to get sharp focus on the eyes, but anything in front from the eyes to the nose and forward is soft and out of focus, as is everything from the eyes and behind. The f/1.8 focussed image is enhancing and highlighting the best parts of the image, whilst not worrying about the detail in the rest of the shot. F/22 on the other hand would have the entire person in focus, including everything in front of and behind them. In this instance, if there was light rain around a person being photographed at f/22, in other words with a great big depth of field, the photo would capture every rain drop. The same photo at f/1.8 would only capture the rain that was on the same focus plane as the subject matter in focus. All rain in front and behind would be soft and blurry.",
"Most cameras are looking \"Down\" on the players, so its harder to see light rain. The few which you can see rain on will be looking ever-so-slightly \"Up\" at players. Plus, cameras have MASSIVE hoods on them to protect the lens."
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efwz9n | Why Oracle vs Google case is so complicated? | I'm reading [wiki]( URL_0 ) and numerous [web]( URL_2 ) [sites]( URL_1 ) about the 10-year legal battle. I even have a programming background and I understand "API" but I don't understand the justice system in the USA. The Federal Circuit reversed twice (yes twice) district court! District court has jury where Federal Circuit does not, so judges ignored what jury think and decide? All this battle is confusing, can someone ELI5? | Technology | explainlikeimfive | {
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"Software copyrights are complicated because they are essentially a stupid idea. If you write a play, you can copyright it and profit from its performance forever†. This is because your play is ART, and ART is decorative, so society encourages its production in order to have decorative things. If you invent a machine that makes paint, you can patent it and for 17 years nobody else can profit from selling your machine. You can license the machine with any restrictions you choose, including legal kickbacks to you. This is because TECHNOLOGY is useful, so society encourages the advancement of useful things. Is software ART or TECHNOLOGY? This legal question has been argued for a long time. Some software owners have gone down the patent road, and others down the copyright road. Both roads lead to legal arguments, and in the US there are still no Supreme Court decisions made by justices who really understood what they were talking about. Perhaps there never will be any such justices/decisions so the questions are unlikely to ever be solved. This is because there is a **huge amount of money at stake**. Imagine if Microsoft lost the ownership and control of all the Windows code they wrote before 2002. This might lead to \"public domain\" operating systems compatible with Windows. Why would anyone every pay Microsoft for their operating system again? What would the company be worth? For this reason, Microsoft, and Oracle, and Google, and almost everybody else with a lot of software intellectual property; argues that software is not TECHNOLOGY, they argue it is ART. Any case which might lead to constraining software to the TECHNOLOGY part of the legal tree has massive implications. Google and Oracle both want to win, but they both don't want the case to be resolved with a decision that the API should have been patented instead and that the patent is now expired. That would be the path to an enormous upset to both companies. † Where \"forever\" means your life plus as many years as Disney needs to keep control of Mickey Mouse.",
"From reading the wikipedia article, it appears that the first case wasn't resolved via jury deliberation. The judge just said \"you can't copyright APIs\" and threw that part of the case out. Oracle appealed, and the higher court said that the API *was* copyrightable, so go back and have a court case on whether it was fair use. The second case *was* resolved via jury. However, a jury's job in this case is not actually to decide whether the law applies, but rather to determine what facts are true. The appeal here found that, in effect, the facts the jury agreed upon do not constitute fair use (essentially, the jury didn't understand the law correctly)",
"the case itself isn't complicated at all, it should be open-and-shut. copyrighting APIs is like copyrighting the concept of public transportation and then suing bus, taxi, train, and airline companies for infringing"
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efx7iw | Bandwidth - How does a satellite send down hundreds of channels of high definition content to televisions all over the country, but my 1MBPS in the connection gets bogged down by five smartphones? | Question from my grandad to his 'techy' kids at Christmas. | Technology | explainlikeimfive | {
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"Think of broadcasting television channels like a movie theater. Each individual theater can display a movie to to huge numbers of people, only limited by how many seats there are and how bright the screen is. If the screen was bright enough and there were enough seats, everyone on earth could watch a movie off that one screen. But when it comes to sending and receiving data to and from a single person, it's less like a movie and more like a phone call. That single satellite up in space can only switch back and forth between separate phone calls so quickly before it's overloaded. So in other words broadcasting is easy. Individual communication is hard.",
"The most important thing to note is that television is a broadcast, while internet is a communication protocol. This is relevant, because the satellite only needs enough bandwidth to send 1 copy of each channel. Everything watching TV is just tuning in to the single copy that is being sent out. Internet, on the other hand, is communication to individual people. If 5 people want to watch a Youtube video, that video has to be sent 5 times, once to each person. In order to make this usable, the *massive* bandwidth that exists gets split up between everyone. In practical terms, this means that satellite TV probably has Gigabytes of bandwidth, hence how it can support so many channels. The internet *also* has Gigabytes of bandwidth, but that is shared among many people, so your \"share\" is only 1MB",
"So traditional TV is done what’s called Over-The-Air (OTA) as well as Cable and Satellite. It’s really a one way communication, the Aerials in your area, cable company, and Satellite TV provider BLAST their signal out to anyone who is can/is allowed to hear the signal. With the internet, you have a two way communication. Download and Upload, in addition you have many devices downloading and uploading at the same time. When that signal is blasted from the Internet Provider it isn’t meant for the masses, it’s meant for the device that asked for the information- and the data coming has to play nice with everyone else’s data, even if that means slowing down or even getting interference and dropping some data. The thing is it’s so fast that your device can ask for that data again or even better- correct that data and get you what you need. So your 1Mbps like connected to 5 smartphones is basically acting like a slow freeway at this point. If all smartphones want to us the 1Mbps at the same time you’re going to have problems. Routers and other networking hardware have software built in that can dedicate a certain amount of data to a device for a consistent experience, coming from a 1Mbps that route would probably make things worse. Your TVs (and phones) work fine due to their connection being on a different platform and only having to receive the signal."
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efyc37 | If rifle barrels are rifled, made to fit 1 type of bullet and last a long time, how come shotgun barrels arent destroyed after having a bunch of metal shot bouncing around in them? | Technology | explainlikeimfive | {
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"text": [
"Most shotgun barrels are smooth bore, meaning that they are a straight pipe with smooth sides. The shot is held together by a \"wad\" which is like a little cup that separates the shot from the powder. Rifled shotgun barrels are available for slugs, though.",
"As others have posted, modern shotguns use a cup/wad that contains the shot as it travels down the barrel. Muzzle-loaders and older shotguns generally don't bother with a shot cup. So long as you only fire lead shot you don't have significant problems with barrel wear because the lead shot is much, much softer than the hardened steel barrel. When lead and steel meet, steel wins and the lead deforms. The issue you *do* run into is lead fouling in the barrel, but that's solved by periodic cleaning and really isn't a major problem when firing shot unless it's *really* severe.",
"Just to add to the already adequate answers here, rifling has nothing to do with the durability or the lifespan of a barrel. It's done to cause the bullet to spin. The spin stabilizes the flight of the bullet causing increased accuracy. This is not necessary for shotguns, especially with bird shot."
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efz7n7 | AV1 vs VP9 Video, which one is better? | YouTube's experimental video section lets me change the streaming from VP9 to AV1, but I can't find a simple explanation for why I would want to do this. What actually changes? Will I notice it? | Technology | explainlikeimfive | {
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"AV1 provides better image quality for the same file size no doubt, but it's a rather new codec and you may find the CPU requirements to play it to be abnormally high. You most likely can't get your video card to assist in playback like H264 and VP9 do. Laptops likely stand no chance of playing back this video today. If your system can handle the video without stuttering, it should look better and/or take less bandwidth. If you have plenty of bandwidth available to stream videos all day, I wouldn't worry about it."
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eg02gi | what's the difference(s) between a gaming mouse and a regular computer mouse? | Technology | explainlikeimfive | {
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"text": [
"Generally speaking, higher DPI/precision, faster response rates, and more likely to have more buttons or other features like alterable weights. Some of these features can be found in other more business-oriented mice, but outside of gaming generally these aren't features most people want to spend money for.",
"I dont game on CPUs but buy gaming ¿mice? More durable, responsive, and can configure buttons as shortcuts like cut , paste. Again they last."
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eg1dd5 | Why are noise-isolating headphones so bad at blocking out certain noises? | I had a burrito covered in foil for lunch and it sounded like I was in WW2. | Technology | explainlikeimfive | {
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"To understand noise cancellation, you first need to recognize that sound is just a bunch of overlaid waves of varying frequencies. If I want to 'cancel' one of those waves, all I need to do is add a wave of the same frequency/amplitude shifted 180 degrees. Put another way, if I record a sound and delay the playback just the right amount, I will be able to nullify a specific frequency. However, this is dependent on the sound remaining the same over time. I'm not actually cancelling sound based on what it is now. I'm cancelling it based on what it was in the past. If the sound has changed between then and now, I'm going to get it wrong, the sounds won't cancel and it will just be a mess. Now, for sounds like an airplane engine, noise cancelling works amazingly well. It's a low frequency sound of nearly constant amplitude that lasts for much longer than our delay period. Our noise cancelling headphones can eliminate it with ease. While there's going to be a bit a muddiness when the airplane engine starts up and when it shuts down, that's nothing compared to the hours where we're cancelling it just fine. But think about your foil-wrapped burrito. Every time you crinkle it, you're creating a very short duration impulse of sound. This impulse cannot be predicted by your noise cancellation. So what happens is that it goes through three steps: 1. Not cancelling anything, hearing tin foil full volume. The noise cancellation hasn't 'caught up' to the external noise yet. 2. Cancelling the tinfoil. The noise cancellation finally catches up and - for the briefest of moments - is able to compensate. 3. Attempting to cancel the now absent tinfoil sound. The noise cancellation still thinks you're crinkling but you've stopped. As a result, the noise cancellation is actually adding crinkling to what you're hearing that wasn't there in the first place. If Step #2 above is short enough, your noise cancellation actually ends up doubling the amount of sound an external source creates due to this delay issue."
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eg2tsk | How motion sensors actually work | Technology | explainlikeimfive | {
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"text": [
"Depends on the type of sensor. The three most common are laser, acoustic and IR. Laser sensors have a sender and a receiver for a small focused laser beam. When something passes through that beam, it gets interrupted and the receiver notices a sudden lapse in signal, which causes the trigger. Acccoustic sensors send out an ultrasound a couple of times every second and measure the reflection, if anything in the room moves or changes the position, it will affect the way the ultra sound signal is reflected and the sensor will pick up that difference and trigger the alarm. Infrared sensors are essentially heat vision cameras that are programmed to scan the incoming video feed, and if too many pixels change too fast, which is what would happen is a warm/hot body of a person moves, they trigger the alarm. Laser sensors are generally used in high security settings, since they are harder to bypass than IR sensors, IR is usually the more commercial/public type because since it's not focused as single sensor can survey a large area, and it's less susceptible to false alarms since it ignores the movement of things that aren't warm.",
"Generally, they map out whatever area they're in with lasers/sonar/whatever their sensor is, and then constantly check it multiple times per second. If they detect an object there that wasn't before, then they trip the alarm"
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eg6255 | Why do pixels on some screens appear to change color when viewed from different angles? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"An LCD screen is made up of layers that are polarized to control how light shines through them. The polarized layers are like blinds in your house - they only let light shine through when they're aligned (opened). They make different colours and shades by lining the blinds up on the coloured layer and the polarization layer to varying degrees - better aligned means more light gets through so a brighter more saturated colour on the screen. An LCD screen with the polarization filter removed just looks uniformly white since nothing is sorting all the colour coming out of it. Now, imagine you are standing close to a window and the blinds are lined up to let you look straight out. The thickness 9f the slats, though, means that if you just angle your eyes up or down your view of the ground or sky is partially blocked by the blinds (even though they are opened) so you can't see those directions as well. Now, pick a car parked across the street and crouch - when your viewing angle changes relative to the alignment of the blinds, your view out the window changes when your viewing position or viewing angle changes even though it is the same window and the same view. Back to that LCD monitor - the way it is built will determine the distance from the actual array that makes the colours to the polarization layer that let's you see those colours and that distance is like the thickness of the slats in your window blinds. Thicker slats will change your view more when your head moves or you angle your eyes looking out the window, and looser (read: cheaper) tolerances or thicker (read: cheaper) panel layers will cause more of an offset between the polarization and LCD array which will impact how the polarization filter sorts those colours from your viewpoint and in turn leads to odd colours, saturation issues, and sometimes a complete negative image if it gets bad enough. Due to differences in technology (permissive v.s. backlit) OLED and plasma displays do not have this problem."
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eg64wq | How do web addresses work? The information is stored on a server somewhere in the world, there are tons of servers, and nothing in the url seems to act like directions on how to get there, but lo and behold the url gets me there everytime. How?!? | Technology | explainlikeimfive | {
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"ELI3 Version: Say you're at a party and you want to talk to Susan. Susan may be standing right next to you, so all you have to do is say her name and then you can start chatting. What if she's not right next to you? You ask your friend \"hey, do you know where Susan is?\" If they know, they go and get Susan and bring her to you. If they don't, they then go and ask someone else the same thing until you finally get to someone who can bring her to you.",
"The URL is made of a few, pretty-well defined pieces. Consider a URL like URL_0 as an example. this is going to be an HTTP request, but let's breaking down. The first bit defined the protocol, you'll usually see http or https. The differende is whether security is expected. Plain http opens a connection and starts chatting with the server in text. Using https adds some handshaking and certificate swapping, to help keep the conversation encrypted. The next bit is the server or host name. The URL_1 is a human-readable representation. This leverages a naming system, DNS, which uses a registration system to turn the name into an internet address. The translation happens for you, but if the name cannot resolve to an address, the connection cannot be made. Not resent here, but in the spec and some URLs is a port number. The http protocol defaults to port 80, and the https protocol defaults to 443. These ports are pieces of the network puzzle necessary to make the network connection. Using the URL example so far, your computer will attempt to establish a secure connection, to the server based on the DNS results for the server name, on the default port. Once the security handshake is complete, the rest of the URL comes into play. After the server or port, is the path. The path /r/somesub needs to have meaning on the server. In this example, we'll also guess the URL is being opened by a web browser. If that was a lil you clicked on, the browser would do what's called a GET. Very technically, what happens is that server connection is established, and then some specific text is exchanged, including the simple command \"GET /r/somesub\" with some other preamble and \"headers.\" In a simple web server, there will be a folder assigned to the root of the web service, which matches the first slash. In that folder is expected to be a folder named r. In the r folder will be a file or folder named somesub. If it's a file, that file's contents are returned. If it's a folder, there's probably a default file I that folder, and its contents are returned. In a more complex example the web server associates some or all of the path with an application. In this example, the r might map to an application that takes the next part of the path as a key to look up in a database. The data returned, in this example a list of posts, is formatted by the r application, and the HTML that renders the contents of somesub gets returned. Further, the path might be longer, and contain many pieces of data. There may also be query parameters, which are the key=value pairsmthat follow a question mark and are separated by ampersands. Even more, there might be data passed with the server connection information, but not part of the path. This is well documented, and there are many good documents, videos, and other descriptions."
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egb1y7 | What does the "seeding" process after a torrent is done downloading mean ? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"Torrenting is a type of peer-to-peer network for downloading files. That means that, instead of the file being on a big server owned by a website, the file is shared from your computer. In order for you to download it, someone else has to keep it available for upload; in order for someone else to download it, you have to keep it available for upload. Keeping it available for other people to download from you is called \"Seeding\". The directory services that you use to find files, called Torrent Trackers, sometimes have rules on who can use them. Sometimes those rules require you to Seed as much, or more than, you download, to ensure that files remain available and that you don't just download whatever you want and leave other people without that file.",
"\"seeding\" is a term used to refer to a user who has a complete [or partial] copy of a torrent, isn't trying to download any more of it, and is able to provide parts of it to other users trying to download the torrent."
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egbslv | Why do why have to turn on airplane mode when in flight, what happens if we don't. | Technology | explainlikeimfive | {
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"text": [
"Nothing happens if you don’t. As to why? Because when mobiles phones first started gaining wide adoption airlines didn’t know if the emissions from the phone would interfere with aircraft systems. So to eliminate any potential liability they may have faced in the event of an accident that may have been in any way tied to mobile phone use and interference with aircraft systems, they decided to forbid their use during flight. In other words, it was a way to limit their potential liability. There are probably other reasons as well, like folks paying attention to a phone aren’t paying attention to commands/instructions from the flight crew."
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eggk6x | How does steam cleaning actually work? How does steam actually loosen dirt? | Also, as a corollary, does using hot water for washing dishes vs cold water do the same thing? I did search and didn't find anything that actually explains the process, mostly discussions about killing germs which I get. | Technology | explainlikeimfive | {
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"As for washing dishes, fat \"dissolves\" or rather mixes with water much better with increased temperature. You can clean your plates with cold water but it is much easier and even cleaner with hot/warm water. Try it with a pan yourself. Hot water will almost always clean it withour much effort, cold water will just drip off. And like that a steam cleaner works as well. The hot temperature, moisture and sometimes even pressure of the steam help lossen dirt, \"melting\" fat or thicken proteins to be picked up easily."
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egkuyb | Why are there so many Microsoft Visual C++ Redistributable installations on my computer? Surely one for each year is enough? | Technology | explainlikeimfive | {
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"text": [
"Each program will require a specific version of the library, and if 2 programs point to slightly different versions we can't just pick 1 because, while unlikely, using the wrong version could result in different things happening. So, why so many versions? Well, patches mainly. A lot of bugs get found over the course of a year, and they (hopefully) get fixed as fast as they are found. Waiting a full year to release a bugfix would be frustrating to users, and possibly downright dangerous if the bug is a security flaw. So, many releases happen each year."
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egn061 | What's the significance of Russia disconnecting from the internet? | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"It’s laying the ground work for any country, but specifically Russia in this case, to create an echo chamber and to control the flow of information. The Russian government can basically censor its citizens and determine the information they can have access to."
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egn2hn | - What is the difference between HAM radio and how cel phones work? | ELI5 - What is the difference between HAM radio and how cel phones work? How similar are they, and how are they different? | Technology | explainlikeimfive | {
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"text": [
"In the US and most countries, amateur radio transmissions have to be public, they cannot be encrypted, anyone can listen in. Cell phones, one the other hand, take great pains to ensure only the intended recipient has access to the information being broadast. Amateur radios can transmit at higher power, up to 1500 W in the US, while cell phones are usually less than 5 watts to limit interference. This also means cell phone signals don't travel as far and have to be handed off from tower to tower. Amateur radio is usually going to be point to point, although there are various repeaters and gateways available. Finally, many amateur frequencies can skip off the atmosphere and reach hundreds, even thousands of miles. Cell phone frequencies specifically avoid this to limit interference. Besides that, they have lots in common. They both transmit using radio waves, they both can be analog or digital, and both can be used to transmit voice or data."
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egn6ox | What makes MD5 such a bad hashing algorithm? | Edit: Asking more in the sense of what makes the algorithms process worse than others, sorry for the ambiguity. | Technology | explainlikeimfive | {
"a_id": [
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"text": [
"A couple of things: 1) It's very fast. \"How is that a disadvantage?\" you may ask. Don't we want computers to be fast? Well, not in this case. For one, you don't need the speed. If your login takes 500 ms instead of 0.5 ms because of a slow hash function, you don't really mind. On the other hand, being able to calculate a billion MD5 hashes per second instead of ten thousand increases the speed of brute force attacks significantly, making your hashes less secure. This is bad in it's own right, but it doesn't even matter with MD5, because 2) It's susceptible to so called \"collision attacks\". A collision attack operates on a simple principle: since a hash function produces a fixed length output from variable length input, there will be multiple inputs with the same hash. If I can craft my own input with the expected hash, I can pass of forged things as valid. By their nature, all hash functions have collisions, but for *good* hash functions finding these collisions should be no easier than just guessing. For MD5, it is *significantly* easier, making it broken by today's metrics.",
"One of the primary ways to measure the strength of a supposedly cryptographically secure hashing algorithm is *collision resistance.* If hash has a 128-bit output (like MD5 does), it should take on average 2^(128-1) guesses before you find two values that hash to the same result. Since it was first introduced in 1991, vulnerabilities have been found that reduced the number of guesses required, and at the same time computer hardware improved so more guesses could be made per second. Last I heard they are are down to around 2^(20) \\~= 1 billion guesses, which takes a few seconds on a modern GPU. While some algorithms are clearly better designed than others, a lot of it comes down to novelty. People have been banging on MD5 for nearly 30 years, so it is no surprise the vulnerabilities were eventually found. All hashing algorithms are going to have some kind of vulnerability, it all comes down to an arms race between algorithm authors and cryptoanalysts.",
"Several of the other comments already say it's possible to generate a hash collision. There are some specifics about this that I think are important: it is possible to create two messages with the same hash. It is not possible to create a message with a specific hash. So you create two documents with the same hash, but it's not possible to create a document that matches the hash of another, given, document. You need to control and change both documents to create a collision. In other words, MD5 is still [preimage resistant]( URL_0 ), but not [collision resistant]( URL_1 )."
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egod6n | To process images, a computer assigns red, green and blue values to every pixel. How does a computer manage sound? What are the values assigned? | Technology | explainlikeimfive | {
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"All sound waves, even complex ones like talking or instruments are just single intensities at single moments in time. You assign each value in time an intensity and when you play it back you get the whole sound. Depending on how finely you chop up the timeline changes how good the sound will be reproduced.",
"For sound it's actually not all that difficult. Sound is pressure waves in the air. You record the pressure very quickly (we're talking like 44 thousand times a second for CDs). When you play it back you move the speakers at the same rate. The speaker moving causes pressure changes in the air and Bingo.",
"almost the same way, the amplitude of the air pressure. At t=0s, amplitude=0.4 At t=0.00001s, amplitude=0.402 ... It looks like it takes a lot of data for any significant length, but computers are good at stupid but large problems. You can then store multiple amplitudes for stereo left/right or even center/rear etc. The next step is then usually to compress the data for transmission."
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egs55p | How does turning it off and on again fix a problem with certain technology? e.g internet router | Technology | explainlikeimfive | {
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"Most systems (routers, switches, etc) have two sets of memory, one of which contains the basics operating system and instructions and the other that has the actually running version and every change you've made. Occasionally, as part of the running, errors develop our the memory gets full (such as with files or logs or other misc stuff) or other issues develop. Turning it off and on again. Turning it off and on again clears out the running version and resets it to the saved one again with whatever the default settings (or most recently saved settings) are, without the errors (usually) sms with an empty running memory, etc."
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egtadw | How does my phone detect that there's water in the charging port? | So the other day, I was taking a bath and accidentally dropped my phone into the water. Since it's waterproof, that isn't such a big issue, however, when I picked it back up and wiped most of the water off, I checked the notifications and one of the notifications said that the phone detected water in the charging port. How does it do that? | Technology | explainlikeimfive | {
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"There are likely wires/contacts in the port which always have a low potential. The phone monitors them and if current begins flowing between them then it signals something is in the port, most likely water.",
"It measured the resistance between contacts of the port. Since the water in your bath was not a distilled one, the electrical resistance was dramatically lower than in case of air."
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egtrh9 | Does “dark mode” on phone and computer settings really help our eyes? | What is the science behind a darker screen being better for our eyes? People at work claim our main system we use when put in dark mode is so much easier on their eyes... and I scroll reddit on dark mode for hours and it seems more comfortable. | Technology | explainlikeimfive | {
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"It is less about your eyes and more about your brain. Light in general and blue light signals your brain that it is day time and that it should remain alert, which will throw off your circadian rhythms and make it harder to get good sleep."
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egvxsf | Why do downloads slow down near the end? | Technology | explainlikeimfive | {
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"If you’re talking about torrents, then think of a download as putting together a 1000 piece puzzle, but with the pieces all spread through your house. You have to search for them before you can put them in place. So starting to put the puzzle together goes fast initially, because you can easily find the pieces. But as you get near the end of the download, most of the pieces, you’ve already found, and you need to search harder for the last few. That’s the same with a torrent, and that’s why the last few % usually takes longer.",
"Most of the time a download is doing more than just downloading. The more complicated other stuff happens during the last few percent, like error checking. Other stuff also happens, but the big thing is virus and error checking.",
"When you are carrying in groceries you are pretty efficient taking them inside the house from the car. You grab some bags and walk them in not being too concerned with contents. Once inside it takes longer to fully finish putting them away as now you have to go through the bags putting everything in the right spot and double checking you got everything and mom didn’t forget the Capri Sun. Same for an internet download. The streams of data coming are pretty efficient as it’s being sent across the internet to your house. Towards the end when your computer takes more time putting it all together and making sure it got everything."
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egww1f | What's the difference between CD-R and CD+R? | Technology | explainlikeimfive | {
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"Do you mean DVD-r and DVD+r? DVD-R is from 1997 and has a different way to line up the lasers than DVD+R which was created in 2002. This makes a difference in some old DVD players. Most DVD drives are compatible with both so it doesn't make much difference.",
"Nothing, nowadays. In the 90s and early 00s, some devices could only read one or the other. I’m sure if you googled it, more would come up considering this has been almost 20 years in the making.",
"There's no such thing as CD+R. There is DVD-R, DVD-RW and DVD+R, DVD+RW The + DVDs where developed later than the - style, and was primarily intended and developed to make improvements on the technical of writing and reading DVD data (the actual specifics aren't particularly interesting, think of it more like the Version 1 and Version 1.1)"
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egzgn6 | How does memory foam work exactly? | Is it a relatively new technology? Does it cause cancer? Does it last longer than a traditional spring mattress? | Technology | explainlikeimfive | {
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"Memory foams are viscoelastic polyurethane foams, which have low resilience. Resilience is the technical term for how fast the foam springs back when compressed. The foam industry uses a standard ball bounce test, where they drop a steel ball form a certain height and literally see how high it bounces. Standard polyurethane comfort foams have pretty high resilience, with ball rebounds in the 40%-45% range. Memory foams measure in the 10%-15% range. They tend to feel \"dead\" compared to standard foam. Note that this isn't how hard the foam feels, how supportive it is, or how dense it is - those are each different properties that can be measured and controlled in the polyurethane formulation. Now, here's the good part. Resilience is usually a function of temperature. A warm foam is much springier than a cold foam, and that property can be manipulated by how much of what kinds of polymers go into the foam formulation. Heat-activated viscoelastic foams are tuned to become substantially more resilient between room temperature and body temperature. When you warm up part of the memory foam, it conforms to your shape. When you get up, they hold their shape! That can be a down side in a mattress, where rolling over puts you onto cold hard foam until your body heat can activate it again to conform to your new position. Note that most modern foam mattresses today have only a layer of memory foam among other layers of different kinds of foams. For example, the top few inches might be special high-resilience foam, with another couple inches of memory foam, and the bottom half being standard supportive foam. For history, it was invited in the 60s by NASA for cushioning aircraft cockpit seats. In the 80s they released the technology to the public. In the 90s Tempur-Pedic brought it to market. Since then, costs have come down substantially and memory foam had shown up in all kinds of applications besides beds, cushions, and pillows. Foams are very safe by the time they get to the consumer. The actual process of making a polyurethane foam involves highly reactivate isocyanates, which can be a severe respiratory irritant. But, they react very quickly during the foaming (on the order of minutes), and any excess isocyanate is consumed when it reacts with humidity in the air. Consumer goods like mattresses need to pass testing like CertiPUR to prove that there are extremely low levels of organic compounds evaporating out of the foam. Generally, a foam mattress lasts just as long as a spring mattress, in the range of 8-12 years."
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eh0lnw | how do traffic light sensors work? | Do they sense the weight of a vehicle on a certain area before the stop line? | Technology | explainlikeimfive | {
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"It varies. But modern sensors are a buried copper wire connected to a sensor on the controller. When you pull up to a traffic light the motion of the conductive metal of your car induces a current in the wire. The current triggers the sensor begins a timer for the light cycle. There is nothing to do with weight.",
"Generally not weight. Usually work like a metal detector - the presence of metal near them changes electrical flow (inductance actually). They are a wire loop embedded in the road connected to the signal control box, and changes to the loop's inductance sends a signal to the control box.",
"Weight is an option - a section of pavement is allowed to move up or down and the movement is detected. Alternatively, they use large coils underground. By moving electrons in these coils, electrons in nearby metal are also moved, and this changes how easily the electrons in the original foils move. When a car parks on top of such a coil, the metal is detected by the coil."
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eh1wou | Why can't we see the flag on the moon even with the super powerful telescopes? | There are pictures of Mars Rover on Mars taken from passing by satellites but never a picture of the flag on the Moon | Technology | explainlikeimfive | {
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"So the flag on the moon is way too small to be seen by our strongest telescopes as it’s only about 4ft wide and to see something that small you would need a roughly 200 meter/650ft wide telescope to see it. To my knowledge we have 10 meter telescopes and that simply just isn’t large enough to show up discernibly in view. While the flag can technically be seen in a picture or by our eyes through a telescope, it just wouldn’t be clear enough with the technology we currently have to be recognized as the flag.",
"The distance between the Earth and Moon is simply too great to get that level of resolution. Not to mention, the flag is supposedly bleached by the sun. Even with a massive telescope, you'd then have to deal with distortions created by the Earth's atmosphere and light pollution. If passing satellites are orbiting Mars, they would be significantly closer to the surface, in the order of only 100 or so kilometers, with fewer atmospheric distortions viewing from space as opposed to from a planet's surface. We can, however, fire lasers at the Moon and record their reflection, because the Apollo missions also left big complex mirrors for this purpose. The fact that we can measure this reflection means they are there (destroying any hoax landing conspiracy argument) and can measure and confirm the distance to the Moon.",
"> There are pictures of Mars Rover on Mars taken from passing by satellites but never a picture of the flag on the Moon Yes, and, on earth, spy satellites can easily image flags; those satellites are sometimes less than 500 & #8239;km away from the target. The moon is 380 & #8239;000 & #8239;km, or about 800 times farther away. We don't have any telescopes nearly that much more powerful than spy satellites.",
"Via Wikipedia: Since the nylon flag was purchased from a government catalog, it was not designed to handle the harsh conditions of space. Some experts theorize that the colors of some flags may have turned white due to sunlight and space radiation, or that the fabric might have disintegrated entirely.[18] A review of photographs taken by the Lunar Reconnaissance Orbiter (LRO) indicates that flags placed during the Apollo 12, Apollo 16, and Apollo 17 missions were still standing as of 2012.[12] Due to the resolution of the LRO cameras, shadows from the fabric of the flag can be seen but the pole cannot, showing that the flags did not disintegrate entirely.[19] A photo review of the Apollo 11 site shows that Aldrin's observation that the flag fell over was likely correct, as no flag was seen in the images.[20] As of 2012, experts were unable to determine if the Apollo 14 and Apollo 15 flags were still standing.[21]",
"Just want to add some more details to the answers here. The angular resolution of a telescope is determined by the diameter of the telescope and the frequency of light, if you want to see it yourself then we're limited to visual light (~500nm) and so all we can do is increase the diameter of the telescope. The angular resolution is given by something called the [Rayleigh Criterion]( URL_0 ), which tells us how close two light sources can be to each other before they start blending together and appearing to be a single object, this relation is approximately θ≈1.22λ/D, where θ is the angle in radians, λ is the wavelength, and D is the diameter. We can translate between distances across the moon's surface and angular size as viewed from earth using some basic trigonometry (2tan(θ/2)=size/distance). Now we can calculate what a telescope can see on the moon. A large telescope in the lifetime of Isaac Newton could be ~6 inches, this would give an angular resolution of 0.000004 radians, which corresponds to 1540m on the moon as the smallest resolvable size. That's not very good. Let's take Hubble instead, at 94.5 inches it has an angular resolution of 0.00000003 radians, or about 100m on the moon. Still no good. The largest telescope on Earth is 10m and even that only gives about 23m resolution on the moon, not nearly good enough for viewing a flag! To get a resolution of 1m on the moon would take about 250m in diameter! This of course doesn't take into account atmospheric effects and only gives the minimum resolvable size to discern two distinct light sources, if they just blend into the background then it'll be even harder. **However**, getting closer to the moon allows better views, such as [this image]( URL_1 ), taken by the Lunar Reconnaissance Orbiter.",
"Despite being the closest item to the earth, the moon is still a considerable distance away from us here in the ground - 384,400 km to be reasonably exact. To take a clear photo at this distance requires a huge telescope, far larger than anything we have available right now. There images of the Mars rovers however were taken from much closer ranges - similar to some of the satellites orbiting earth in the hundred kilometer ranges (which are very capable of taking clear images of the earth's surface) To put that into perspective, it is the difference between standing and looking at two objects - one about 1-2m away from you, the second about 4km away - thousands of times further away."
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eh2iam | How is 5G going to interfere with weather satellites? | Technology | explainlikeimfive | {
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"Some of the frequency bands that are expected to be used for 5G are currently the bands that most weather radar use to detect precipitation feedback in the atmosphere, as that makes the \"noise\" of different \"intensity\" to show what we know has a weather radar sweep. Those frequencies, if used in 5G communication will give false positives on weather radar in areas of high usage (i.e. cities) causing major weather forecasting computer models to spit out bad data that it can't compensate for.",
"So the weather radar on the side of the highway that’s been there for decades has been “5G” this whole time? And people are worried about the health issues that could arise? People work in the building just below their entire lives."
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eh34sz | The Differences between UART, JTAG, and TTL | Alright so I have been looking into looking underneath the hood of some home automation devices. A lot of people have done similar things with different devices. And UART, JTAG and TTL have all come up in these different write ups I have been reading about. So I have been understanding UART and JTAG to get me the same thing, a shell or access to the boot loader for these different devices. But they are 2 separate protocols so I just don't understand what I am really wanting. Especially when it comes to trying USB to one of the breakout board so I can actually get the serial connection to these devices. | Technology | explainlikeimfive | {
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"This is from many years ago (ie it could have changed) UART (universal asynchronous receiver transmitter) means to expect that the data to be sent and received as a series of pulses (as opposed to parallel address/data) Usually this means 2 to three lines. (receive, transmit, ground) or simply (receive/transmit, ground) TTL (transistor to transistor logic) tells you that the signal is going to be at nominal 0 volts and 5 volts to signify off and on states. (it may allow 3.3v) Older UART devices also used to work at 0v and 12V (or +12v and -12v) so this can be important. JTAG is a type of interface (usually a UART perhaps operating at TTL) that the manufacturer designed in, usually as a debugging interface. This allows the test equipment and folks who work on debugging and repair access to the internal state of the device. A piece of electronic equipment may have several chips that support JTAG and these interfaces can be daisy chained together (with some kind of device selection address) Usually these run at low speeds and is used to get information on status of the individual chips within the equipment (especially when the equipment doesn't work and someone is trying to figure out which chip, if any, is reporting any unusual status) You'll need a manual (for each chip AND the equipment schematic layout) because there is no \"standard\" implementation of JTAG AFAIK."
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eh5ibq | how can the original super mario bros file size only be 32 kilobytes/Kb? | Technology | explainlikeimfive | {
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"The code is very very very very very efficient. Programmers in the 70s and 80s were taught more intensely about how to make your code more efficient because, at the time, resources were *expensive*. Nowadays we have 8GB or even 16GB of RAM that is considered standard. We don't really NEED to worry about efficiency as much as we used to. Everything else is just using efficiency with graphics (i.e. that one shape for every cloud or clump of grass or whatever) and just keep reusing that same thing.",
"Programming back then was different - you had very few resources, so you needed to be efficient - there was no way around it! Also, there weren't so many layers to interact with - your code worked close to metal instead of calling OS functions (like today with the Win32 or DirectX API). Nowadays... well, the whole agile thing put more emphasis on delivering new stuff every 2 weeks instead of efficient programming. But if you want to be amazed with more recent creations, check out a [modern FPS in 96KB]( URL_1 ). And also check out [Pouet demos]( URL_0 ).",
"Don’t forget the simple things, like clouds and trees using the same sprites, any plenty of stuff just being recolored."
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eh5zwe | How does Google/Apple Maps accurately measure traffic on every single road to predict trip time from origin to destination? | In addition to amount of traffic and trip time, how do they know if an accident occurs? I assume it has something to do with satellite imaging and/or tracking individual user’s location that are using the app on their phone. | Technology | explainlikeimfive | {
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"There are quite a few sources of data. Crowd sourced information is very fast and high precision, but can be messy (is the traffic bad, or is this person just driving slow?). This kind of data comes from anonymized reporting while your phone is using its GPS. For example, while you’re using the turn by turn directions, you’re also reporting your own location data (anonymously) which gets combined with other people’s data and turned into one component of the traffic prediction. Another source of data is simply highway patrol. Different states (and countries) have different methods for determining and reporting traffic on major routes, but they almost always have something. This data is very curated and accurate, but sometimes lags behind a bit and only covers major roads. Despite the lag, it can still be a valuable tool for training the predictive model to better understand the more variable patterns produced by the GPS data. And finally of course you have accidents and construction, which are usually reported very quickly, again to highway patrol, and these usually have a comparatively predictable effect on traffic. They can’t be used to give high precision predictions on their own, but taken together with the rest of the data, they’re very valuable.",
"Every android phone periodically reports its location, which allows for traffic flow analysis. Accidents are usually user reported.",
"It sends sacrificial drivers to check alternate routes. If you study this route it is diverting my 2-3min off route to check on previous congestion, first left on screen wasn’t required, could have continued straight through. URL_0",
"I know that sometimes they bin times and then guess. A certain road is busy at certain hours on certain days"
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eh6fmr | what do the Windows updates that don't change anything visible do? | Technology | explainlikeimfive | {
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"A lot of security issue and big fixes. Some time after a part of windows is coded, someone at Microsoft leans that under a very specific set of circumstances, that piece of code might behave unpredictably, lead to a system crash, or allow arbitrary code to be executed with admin privileges. Or sometimes just fix/add an obscure feature that most people don't know about.",
"Patch security holes in the operating system and in Microsoft products that are a part of the operating system, change/add/remove options that you might not have known existed to begin with, rarely make performance improvements."
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eh6jmg | pixel binning | New Samsung S11 is supposed to have a fancy new camera that does this. Started to read this article about it and it made my head hurt. Unhurt my head URL_0 | Technology | explainlikeimfive | {
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"> Pixel binning is the process of combining the electric charge from adjacent CMOS or CCD sensor pixels into one super-pixel, to reduce noise by increasing the signal-to-noise ratio in digital cameras. On the same sensor size, if you combine a group of pixels, you'll make the photo look better because the photo size is much less than what the sensor is made for. The sensor can use the \"extra\" space to take in more light to make photos look better.",
"A pixel on a CMOS sensor transform light into an electric signal. The bigger the pixel the more light is captured. Pixel binning is basically treating 2x2 pixels as a single pixel. Phone manufacturers are already using this technique, because of the current monstruous resolution (up to 48megapixels) Having so much pixels on a small space (phone sensors are obviously much smaller than a DSLR) mean that single pixel is very small and don't capture much light. And so using a 48MGPIX with pixel binning result in having the same resolution as a 12MGPIX without pixel binning. The 48MGPIX number is much more impressive for marketing purposes and that is the first reason why they use pixel binning."
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eha87a | Why does ionising radiation cause cameras to act strangely and/or stop working? | For example in [this picture (the elephants foot)]( URL_1 ) (the elephants foot) where it causes a strange ghostly apparition of a man standing 2 feet away from the most radioactive object in existence, [or in videos where it causes strange dots and static (warning: creepy, its footage from inside Chernobyl Reactor #4)]( URL_0 ) and I don't understand what causes it. | Technology | explainlikeimfive | {
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"Radiation goes through the camera's body and either hits and discolors film (this is how radiation was discovered to begin with: a piece of uranium ore was left in a desk drawer and it spoiled new-in-the-box photography materials) or hits the transistors inside microchips and causes them to activate out of order or hits the image sensor and gets registered as a large amount of light.",
"The ghost image of the person is not an effect of radiation, but an effect of a long film exposure time in low light conditions. When there is low light, you need to keep the shutter open for a long time to get an image because you are letting what sparse light there is hit the film. There is a light source on the room, flashlights, and the person moved through the light field. But since it’s not a lot of light, you only get a partial image."
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ehaoee | How does telling video game cheaters what program they were detected with help them develop better cheats? | Technology | explainlikeimfive | {
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"If you log onto a game and you get busted cheating, and the game says \"We tracked your mouse movements and they were always in a straight line from point to point, and at a constant speed, instead of having some curve in them and variation in speed, like a normal human would do it\" then you would know to rewrite your cheating program to never move your mouse in a straight line from point A to point B, you'd make it move at a random speed with a random amount of curvature to it. Instead they just say \"You were busted cheating. Goodbye.\""
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ehb65u | How google makes profit with some of its services that seems completely free like Maps, Translate or Gmail | Technology | explainlikeimfive | {
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"They provide these services for free because those services are only secondary to how they make their money. They made their money with advertising and data. Data which is used to make better advertising, targeted advertising. You are not Google's \"customer\". You are the product.",
"To start with, Google maps and Gmail isn't free. It is for the general public but for example the Google Maps API (An API is basically just a little app another app can call) pricing table can be found here: [ URL_0 ]( URL_0 ) It's about $7 per 1000 requests depending on the exact request you're using. A lot of companies use an embedded map when doing a search, tracking, all kinds of things. So each time someone goes to that webpage a tracking request is sent to the google maps API. This adds up quick for busy webpages. For example, when they changed their pricing structure recently if I remember right it was going to cost my company $1.5 million extra per year for a little map on our webpage.",
"There are a few reasons. The first is that not every product had to make a profit. Google will often support a project that doesn't seem to have an immediate revenue potential. Some of these may become commercially viable later, some might get rolled into other products, other might get axed. It is all part of the way they approach innovation. Mostly though their products are advertising platforms. Where I live we receive a free local newspaper. I get to read the local news and laugh at small town arguments kicking off in return for the opportunity for them to show me advertising. Many Google products (e.g. gmail) follow a similar model. There is another model that i find interesting, which is where the service is provided in order to extract \"effort\". The early Google CAPTCHA service was a good example of this. The early version of their\"I'm not a robot\" offering asked you to type in two badly written words. Every time users did that they were helping Google transcribe documents. Other examples of this are less obvious: people adding reviews to maps etc.",
"Sweet sweet user data. They collect everything you do with them and sell that info to various research and marketing groups so they can better sell whatever products they're trying to sell or research whatever they're trying to research."
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"url"
] | [
"url"
] |
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