https://www.explainxkcd.com/wiki/api.php?action=feedcontributions&user=141.101.104.143&feedformat=atomexplain xkcd - User contributions [en]2024-03-29T12:38:07ZUser contributionsMediaWiki 1.30.0https://www.explainxkcd.com/wiki/index.php?title=Talk:1941:_Dying_Gift&diff=150908Talk:1941: Dying Gift2018-01-12T15:41:54Z<p>141.101.104.143: </p>
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* Wikipedia has a list of most Foucault pendulums in the world, if anyone wants to try to guess what museum he worked for :) https://en.wikipedia.org/wiki/List_of_Foucault_pendulums [[User:Hawthorn|Hawthorn]] ([[User talk:Hawthorn|talk]]) 12:11, 12 January 2018 (UTC)<br />
** I assumed that his Foucault pendulum was in his own home, rather than in some public place. [[Special:Contributions/141.101.104.143|141.101.104.143]] 15:41, 12 January 2018 (UTC)</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=Talk:1927:_Tinder&diff=149118Talk:1927: Tinder2017-12-12T17:59:48Z<p>141.101.104.143: Cellular</p>
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This comic reminds me of [http://xkcd.com/582] (because of using an inappropriate form of communication in an emergency).<br />
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"Cueball is violating the law by using a cell phone that is not in "airplane mode" when on an airplane.", really? I don't think it's an actual "law" since the entire concept is based on garbage and bullshit (you'd have to be in the cockpit AND within about 2 feet of the equipment in question in order to interfere with it. For both airplanes and hospitals the rule is actually just to try to bully people into being considerate to the people around them). I believe it's just a rule set by the FAA or some other governing body. Also, I believe said rule is limited to during take off and landing, not the entire flight. [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 07:31, 12 December 2017 (UTC)<br />
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*I also wondered about "Cueball is violating the law by using a cell phone that is not in "airplane mode" when on an airplane.", but for a different reason: How do we now that the phone is not in airplane mode, but which activated wifi? As some airlines (at least in Europe) offer wifi on board, it would be quite common (and allowed) to be able to use online services on a phone while flying (but not other wireless signals, e.g. phone calls). [[User:Scm|Scm]] ([[User talk:Scm|talk]]) 09:00, 12 December 2017 (UTC)<br />
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:: Actually, you're correct (at least in the US). However, some countries has actual laws that either explicitly do not allow phone usage on a plane (e.g. Japan) or do not allow it implicitly (In Russia, using licensed radio frequencies above a certain height is not allowed unless the regulator allows that use) - [[Special:Contributions/172.68.144.169|172.68.144.169]] 10:29, 12 December 2017 (UTC)<br />
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::: I understand the reason for turning off cellular connections is not for the safety of the aircraft but the safety of the cellular network. Having phones hopping between cells at 400 mph is out of spec for the technology and causes problems. [[Special:Contributions/141.101.104.143|141.101.104.143]] 17:59, 12 December 2017 (UTC)<br />
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:To suggest that there is a meaningful difference (in this context) between a rule and a law is silly; the FAA can (and has) fined individuals for using cell phones *during takeoff*. Does it matter if the fine was for breaking a rule or for breaking a law?<br />
:More importantly, in the scenario shown Cueball has somehow found himself in the role of PIC (pilot in command) and in an emergency situation. Assuming he declares the emergency he can freely violate any and all FAA rules that he believes will help in resolving the emergency (that's the FAA's rule).<br />
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I'm not sure that the interpretation that he may be making up the emergency to gain matches really makes sense, given the title text - since the radio wouldn't really help him in that case.[[Special:Contributions/141.101.76.16|141.101.76.16]] 17:19, 12 December 2017 (UTC)</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=Talk:1703:_Juno&diff=122993Talk:1703: Juno2016-07-07T16:46:11Z<p>141.101.104.143: </p>
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According to http://www.space.com/18383-how-far-away-is-jupiter.html it is about 600 million miles to Jupiter, and according to http://www.space.com/18477-how-far-away-is-saturn.html it is about 1.7 billion miles to Saturn. So they went the distance to Saturn but ended up in Jupiter. They must have gone i pretty long circles to go 1.7 billion miles to get 600 million miles away. [[User:Aquaplanet|Aquaplanet]] ([[User talk:Aquaplanet|talk]]) 14:46, 6 July 2016 (UTC)<br />
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: That's 1.7 billion ''kilometers''. They lost the {{w|Mars Climate Orbiter}} that way. [[User:.42|.42]] ([[User talk:.42|talk]]) 15:38, 6 July 2016 (UTC)<br />
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: Actually, the space.com website does say Saturn is 1.7 billion miles away ''at its furthest'', just as Jupiter is 600 million miles at its furthest. In either case, interplanetary travel isn't a matter of taking the shortest route. Yes, Juno went 1.7 billion miles to go to Jupiter (anywhere from 365 million to 600 million miles away, currently 370 million according to Google), because it was the easiest / most cost effective (in terms of fuel) way to get there. --[[User:Mr. I|Mr. I]] ([[User talk:Mr. I|talk]]) 15:47, 6 July 2016 (UTC)<br />
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:: Jupiter is actually 872 million km away right now, which just happens to be roughly the current distance to Saturn if kilometers are confused with miles. [[User:.42|.42]] ([[User talk:.42|talk]]) 16:18, 6 July 2016 (UTC)<br />
:::These interesting observations should be included in the explanation --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 17:29, 6 July 2016 (UTC)<br />
::::Here is a cool animation showing the path that Juno took to get to Jupiter: https://66.media.tumblr.com/4e881a0340b323bcdfa3797001ca1c6c/tumblr_o9ua2xrMW11qiz5q7o1_540.gif [[User:Mwburden|mwburden]] ([[User talk:Mwburden|talk]]) 13:31, 7 July 2016 (UTC)<br />
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Of course anyone who has bought a used car off Autotrader will know that how far away something is doesn't necessarily correlate particularly well to how far you have to go to get there [[Special:Contributions/141.101.98.59|141.101.98.59]] 14:57, 6 July 2016 (UTC)<br />
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Several sources have reported that Juno arrived at its Jupiter orbit 1 second off schedule http://www.usatoday.com/story/tech/nation-now/2016/07/06/how-juno-arrived-jupiter-one-second-off-schedule/86745128/. --[[Special:Contributions/108.162.221.13|108.162.221.13]] 15:33, 6 July 2016 (UTC)<br />
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: I was going to come here to ask "Did they really make it within one second? And how do they decide when it is 'in orbit'?", but in that article is a quote "We hit our burn targets within one second" which makes sense - 'in orbit' starts when the engines turn off after the last course correction. {{unsigned ip|108.162.246.73}}<br />
::If Kerbal Space Program has taught me anything, it's that you're "in orbit" from the moment the projected trajectory both no longer intersects with a planet, and puts your craft on a path that remains permanently within the target object's gravity well.[[User:Xseo|Xseo]] ([[User talk:Xseo|talk]]) 17:08, 6 July 2016 (UTC)<br />
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;Blondie as a new character?<br />
2nd time in short order "Blondie" has been the main character. See this [[explain_xkcd:Community_portal/Proposals#New_character_category_for_blonde_woman_news_reporter_.28from_1699.29|Community portal proposal]] regarding new categories and please comment there for or against. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 19:53, 6 July 2016 (UTC)<br />
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;Who says what in the title text?<br />
Given that Juno was connected to both Jupiter and Saturn, the point of the title text is a little obscure. However, it seems fairly clear to me that the first question ("The name wasn't a tip-off?") is supposed to come from the NASA team (i.e., "it didn't tip you off that we were aiming for Saturn?") and that the reply is supposed to come from the press. NASA named the probe. NASA decided where to send it. It makes no sense for the press to ask that first question, or for NASA to assume it was named after Juneau or guess that gravity assist "must be more efficient or something". Kynde appears to disagree with me, however, so perhaps some other people could weigh in and give their views. [[User:Garik|Garik]] ([[User talk:Garik|talk]]) 16:51, 6 July 2016 (UTC)<br />
:Yes I still disagree. To me it seems like a continuation of the conference and it is now the press to speak. And given that I knew Juno to be related to Jupiter but not that she was the daughter of Saturn (and given the reason for the naming in the real world) I would not say that the name in any way would lead anyone to take it as a hint for going to Saturn. But great to discuss it. For sure it was NASA who made the mistake not the press. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 17:24, 6 July 2016 (UTC)<br />
::Now we have both deleted each others edits. So to prevent an edit war I have inserted both versions for now. --[[User:Kynde|Kynde]] ([[User talk:Kynde|talk]]) 17:53, 6 July 2016 (UTC)<br />
::As Homer Simpson would say: "Kids, you're both right!". However my first impromptu interpretation when I read the comic was the first. But after thinking about it, I tend more to the second (with Megan saying the first sentence) and like to present a fourth alternative: Both statements are from the press (different persons, ofc). [[User:Elektrizikekswerk|Elektrizikekswerk]] ([[User talk:Elektrizikekswerk|talk]]) 08:18, 7 July 2016 (UTC)<br />
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Juno: "You Know" - [[Special:Contributions/141.101.104.143|141.101.104.143]] 16:46, 7 July 2016 (UTC)</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=1678:_Recent_Searches&diff=1199671678: Recent Searches2016-05-11T20:35:09Z<p>141.101.104.143: /* Table of searches */</p>
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<div>{{comic<br />
| number = 1678<br />
| date = May 9, 2016<br />
| title = Recent Searches<br />
| image = recent_searches.png<br />
| titletext = autoexec code posted by verified twitter users<br />
}}<br />
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==Explanation==<br />
People often find answers to computer problems by searching on {{w|Google}}, which shows you recent search terms in a drop-down box when you go to search it. Here we see a list of search queries, each of which suggests the author is perversely misusing or overextending some computer technology. The overall impression is of someone technically sophisticated enough to shoot themselves in the foot, and who does not learn any larger lessons despite doing so repeatedly. The title text is another possible entry in this list.<br />
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The caption implies that from Randall's perspective, every computer he uses seems to be broken; he doesn't seem to realise this is because he's the one using them, not because the computers actually start off broken. (For similar themes see also these comics: [[349: Success]], [[1084: Server Problem]], [[1316: Inexplicable]] and [[1586: Keyboard Problems]]).<br />
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([[979|Dear people from the future]], if Google directed you here because it is the most popular result for a problem you are experiencing, this is not the page you were looking for). <br />
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===Table of searches===<br />
{| class="wikitable" border="1" cellpadding="4" style="border-collapse: collapse;"<br />
|-<br />
! width=20% | Search<br />
! Explanation<br />
|-<br />
| [https://www.google.com/search?q=Google+translate+syntax+highlighting Google translate syntax highlighting]<br />
| {{w|Syntax highlighting}} can be used when editing {{w|source code}} to make the code more readable and easier to understand. It is not generally used for natural languages, but {{w|sentence diagram}}s of brief passages are used in language education. {{w|Google Translate}} is used to translate text from one {{w|natural language}} to another. It uses {{w|JavaScript}} <tt>mouseover()</tt> to highlight words as an aid in matching phrases in the source with their translations, but does not apply different highlighting dependent on syntax.<br />
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Alternatively, this could imply that Randall is attempting to translate code from one programming language to another using Google Translate. Success would be unlikely, since the service is not intended for this, {{Citation needed}} and syntactically valid output might further break the computer executing it.<br />
|-<br />
| Autodetect mixed bash zsh<br />
| {{w|bash}} and {{w|Z_shell|zsh}} are two {{w|Command-line_interface|command line interfaces}} for {{w|Unix-like}} OSes. The way to execute commands is almost identical, making detecting a script that contains a mixed syntax nearly impossible.<br />
|-<br />
| CPU temperature sensor limits<br />
| The CPU's temperature sensors exist to tell you when your CPU is becoming dangerously overheated (normally because of a faulty fan or overclocking). Someone who searches for information about the limits of those sensors is presumably expecting to misuse their CPU. Probably also a reference to [[1172: Workflow]].<br />
|-<br />
| GIF to XLS<br />
| .GIF (Graphic Interchange Format) is a file extension used to store images and sequences of images to be displayed as an animation. .XLS is the file extension for Microsoft Excel spreadsheets. The joke is that the two file types are used for different purposes - it's quite normal for someone to want to convert between .GIF, .JPG, .PNG, .BMP files, as these are all image files; or between .XLS, .CSV, and .ODS files, as these all record tabulated information. However, for some reason Randall wants to convert an image file to a spreadsheet. (This is actually possible, because a digital image is essentially an array of colour and brightness values; it just wouldn't be particularly useful for most people. [http://www.think-maths.co.uk/spreadsheet Here] is a webpage with an online converter.)<br />
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An alternate way to convert an image file, such as a .GIF file, into a text-based file like an .XLS file, is through {{w|optical character recognition}} (OCR). This is only effective if the image is a copy (i.e. a scan or reasonably clear photograph) of a document containing letters and words, and neither .GIF nor .XLS are file formats anyone would usually use in that case.<br />
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Matt Parker has done a [https://www.youtube.com/watch?v=UBX2QQHlQ_I stand up routine] about converting these two file types.<br />
|-<br />
| Clock speed jumper sample rate<br />
| A jumper is an intentional short circuit used for selecting options for an electronic circuit. They are usually used where it is not feasible to use programming (such as outputting a byte or word through a port) to alter the selection, such as before the processor even begins executing. A common example would be, on some motherboards, jumpers can be used to alter the clock speeds of various motherboard functions (such as the CPU or the front side bus). These jumpers should ordinarily be modified when the computer is off. However, this search is asking how often the motherboard checks the status of the clock speed jumpers, implying that they intend to change these jumpers while the computer is powered on, and often enough that the sample rate matters (change cpu speed several times a second, by moving jumpers on the motherboard.). That is, of course, a little silly.<br />
|-<br />
| [https://www.google.com/search?q=clean+reinstall+keybinding Clean reinstall keybinding]<br />
| This refers to keybinding, the practice of mapping (binding) a certain key to a certain function (e.g., pressing PRTSC will take a screenshot). Most keyboards do not output characters directly, but only codes for which keys have been pressed (or released). Keybindings translate the pressing of the "A" key on your keyboard into the letter "A" being sent to a program which is reading keyboard input. A "clean reinstall" of keybindings is something that would almost never be necessary - it means Randall has modified his default keybindings to such an extent that his [[1031:_s/keyboard/leopard/|leopard]] has become unusable (similar to [[1284: Improved Keyboard]]), necessitating a "clean reinstall" of the bindings. Alternatively, he might be doing clean reinstalls so often that he wants a keybinding to execute them with minimal loss of time.<br />
|-<br />
| Cron job to update crontab<br />
| {{w|Cron}} is a utility that allows you to schedule commands or scripts to be run periodically. These scheduled jobs are read from a ''crontab'' file. A job that updates the crontab (therefore creating new jobs, removing old ones or editing existing ones) is paramount to a {{w|job scheduler}}, and trying to use cron for such functionality could result in highly unstable functionality (although a crontab could be sensibly regenerated periodically by a set of machines from a master crontab file annotated with per-host directives). This is similar to {{w|self-modifying code}}.<br />
|-<br />
| [https://www.google.com/search?q=fsck+chrome+extension fsck Chrome extension]<br />
| <br />
This is a search for an interface to the Unix '''f'''ile'''s'''ystem che'''ck'''er {{w|fsck}} via third-party software added to Chrome. fsck is a program for checking your filesystem for corruption. Repairing a filesystem this way would be inadvisable. {{Citation needed}} This might indicate confusion about the meaning of the term "online filesystem repair", in which "online" means "while the filesystem is in use" rather than "over the Internet". Alternatively, Randall might want to repair an installation of the operating system Chromium, in a manner less drastic than the {{w|factory reset}} preferred by Google.<br />
|-<br />
| Recursive font<br />
| An idiosyncratic mix of {{w|recursion}} and the font style ''{{w|cursive}}'', referring especially to text handwritten in a flowing manner. {{w|PostScript}} (the language in which {{w|PostScript fonts|some fonts}} are written) is capable of recursion and PostScript Type 3 fonts are able to use the full language. This could create effects like fonts with complicated fractal borders and fill patterns - but the increase in processing time would contribute to seeming brokenness of the computer (or printer) rendering the font.<br />
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A true recursive font would be a form of {{w|fractal}}s.<br />
|-<br />
| Regex matching valid EBNF<br />
| EBNF refers to {{w|Extended Backus–Naur Form}}, which is used to define {{w|formal language}}s. EBNF specifies recursive patterns that are impossible for a {{w|Regular_Expression|regular expression}} (regex) to determine whether it is valid or not. There is some irony in using regex to test the validity of something which ''defines'' the validity of things like regex.<br />
|-<br />
| [https://www.google.com/search?q=Hardlinks+Turing+complete Hardlinks Turing complete]<br />
| In some filesystems, for example {{w|ext4}} and {{w|NTFS}}, a single file may be referenced by different names anywhere in the filesystem. These filenames are termed "hard links" to the file because they are automatically resolved by the operating system to the file metadata. "Soft" or "symbolic" links are resolved indirectly via a pathname, which may reside anywhere. A file is deleted when the last hard link to it is unlinked; a soft link exists independently of its target. In fact, the target need not exist, in which case this is often called a dangling symbolic link.<br />
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{{w|Turing completeness}} is the {{w|computational complexity}} required to simulate any {{w|computable function}} (given an infinite amount of memory). Recently there have been cases where [http://beza1e1.tuxen.de/articles/accidentally_turing_complete.html unexpected mechanisms] from card games to text parsers were proved to be Turing complete. Hardlinks being Turing complete would imply that creating and deleting hardlinks alone is enough to satisfy the requirements of Turing completeness.<br />
|-<br />
| Opposite of safe mode<br />
| {{w|Safe mode}} is a diagnostic mode of an operating system or application which allows the user to troubleshoot problems by disabling unnecessary functionality. The "opposite of safe mode" implies a "dangerous" mode where the purpose is to allow uselessly dangerous action, like {{w|sudo}}.<br />
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It's also possible that Randall sees safe mode so often that he sees regular mode as an unusual and unique state and needs help navigating back to it.<br />
|-<br />
| Predictive touchpad<br />
| {{w|Predictive text}} is a feature of many smartphone keyboards that predicts the most likely word the user wishes to type, and then gives the user the option to place the word in the sentence without typing the whole word. A {{w|touchpad}} is a computer pointing device, similar to a {{w|computer mouse}}. The idea of a "predictive touchpad" seems absurd because, as opposed to typed words, there are not a limited number of swipe combinations that are possible on a touchpad. A "predictive touchpad" implies that a computer could predict where the user was going to move the mouse or click, which in this case would seem to defeat the purpose of a user input device. {{Citation needed}}.<br />
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Interestingly, a version of Linux {{Citation needed}} had a predictive cursor option, where the cursor jumped to the nearest button (like window close) when it moved near to but didn't quite reach that button.<br />
|-<br />
| Google docs from bootloader<br />
| Google docs relies on programs and libraries much more complex than a {{w|bootloader}} (a very small program running immediately after boot, mainly for loading the OS) could run.<br />
|-<br />
| Hardware acceleration red channel only<br />
| {{w|Hardware acceleration}} means that certain calculations are not performed by the computer's {{w|CPU}} but by a "specialized" processor, e.g. a {{w|GPU}} which is part of the graphics adapter. This speeds up output, especially if complex 3D calculations are required and reduces CPU load. To use this function only on a single color channel seems pretty useless, but one may want to troubleshoot a program that displays only red when hardware acceleration is enabled.<br />
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While graphics cards are most commonly used with three or four channels (red, green, blue, and sometimes alpha), they do support two-channel or single-channel images. An 8-bit single-channel image would use the format '[https://www.opengl.org/wiki/Image_Load_Store#Format_qualifiers R8]', which is indeed 'red channel only'. This type of image could be used to store monochrome images or non-image data.<br />
|-<br />
| autoexec code posted by verified twitter users. ('''Title text''')<br />
| Automatically executing code from the Internet is generally a terrible idea, because it could be written by someone with malicious intent and harm your computer. The joke here is that the code would only be executed if written by someone who has been "verified" on Twitter. Twitter's verification service only serves to show that a user is who they claim to be, not whether or not their code can be trusted, so this would provide little protection. Usually, twitter verification is used by celebrities so they can be distinguished from people claiming to be them. The line implies that Randall is only interested in running code posted by celebrities.<br />
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Most code downloaded from authentic sources, such as Windows and Linux, is verified by a cryptographic signature -- such packages signed by a true trusted source authenticating the origin of the software, and the are frequently executed on your computer automatically and it forms the basis for auto-updates of for example your Chrome browser, any automatically updated linux package, and everything automatically updated by Windows 10. The joke here is that "verified" have different meaning for twitter and cryptography.<br />
|-<br />
|}<br />
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==Transcript==<br />
:[Coloured and styled as the real logo:]<br />
:<big><font color="blue">G</font color><font color="red">o</font color><font color="orange">o</font color><font color="blue">g</font color><font color="green">l</font color><font color="red">e</font color></big><br />
<br />
:[Google Search bar, with a drop down box with faded text, implying recent searches]<br />
:Google translate syntax highlighting<br />
:Autodetect mixed bash zsh<br />
:CPU temperature sensor limits<br />
:GIF to XLS<br />
:Clock speed jumper sample rate<br />
:Clean reinstall keybinding<br />
:Cron job to update crontab<br />
:fsck Chrome extension<br />
:Recursive font<br />
:Regex matching valid EBNF<br />
:Hardlinks Turing complete<br />
:Opposite of safe mode<br />
:Predictive touchpad<br />
:Google docs from bootloader<br />
:Hardware acceleration red channel only<br />
<br />
:[Caption below the panel:]<br />
:'''I have no idea why my computers are always broken.'''<br />
<br />
{{comic discussion}}<br />
<br />
[[Category:Comics with color]]<br />
[[Category:Google Search]]</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=1442:_Chemistry&diff=782891442: Chemistry2014-11-04T14:41:51Z<p>141.101.104.143: misspelled "alkanes"</p>
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<div>{{comic<br />
| number = 1442<br />
| date = November 3, 2014<br />
| title = Chemistry<br />
| image = chemistry.png<br />
| titletext = These are all sans-serif compounds. Serif compounds are dramatically different and usually much more reactive.<br />
}}<br />
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==Explanation==<br />
{{Incomplete|Rough draft. Need to explain the origin of "Mydrane" along with general improvements and proof reading.}}<br />
Chemical bonding is a well-known subject which explains the formation of {{w|molecule}}s from {{w|atom}}s. This comic refers to three {{w|chemical element}}s: Carbon (C), Hydrogen (H), and Oxygen (O). In real chemistry, the formation of bonds between atoms depends on the number of valence electrons each atom has, and how accessible those electrons are for bonding. The comic jokingly replaces valence electron theory with a theory that the number of bonds an atom can form depends on the number of {{w|Leaf vertex|leaf vertices}} possessed by the chemical symbol's letter. A leaf vertex is a vertex having only one edge connecting to one other vertex. "H" for example, the chemical symbol of Hydrogen, has 4 leaf vertices. This is shown in the comic by the four half-circles placed at each leaf vertex of the "H". Thus, in the comic's theory, elemental hydrogen can form 4 bonds. Oxygen, however, having the chemical symbol "O", has no leaf vertices, and according to the comic's theory should not bond to anything, and is therefore inert.<br />
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Of course, the theory is completely inconsistent with observed chemistry. While the comic declares oxygen is inert and forms no bonds, this is not really the case: the two unpaired valence electrons in a lone oxygen atom makes oxygen reactive, and oxygen readily form molecules. Diatomic oxygen, O<sub>2</sub>, makes up about 20.9% of Earth's atmosphere, and is essential for aerobic life, including human life. Similarly, a water molecule consists of an oxygen atom tightly bonded to two hydrogen atoms.<br />
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By observing real chemical compounds, chemists have deduced that hydrogen atoms really have 1 valence electron, carbon 4 and oxygen 6, allowing Hydrogen to have up to 1 bond, carbon up to 4, and oxygen up to 2. Thus it is Carbon which can have up to four bonds, and really is {{w|graphite|often found}} in {{w|diamond|crystalline form}} in nature (e.g., diamonds, coal); Oxygen which can have up to 2 bonds, and can combine with Carbon to form CO<sub>2</sub> (instead of C<sub>2</sub>H in the comic). We can see here that Randall is giving "typographic" Hydrogen real-life Carbon qualities, since "typographic" hydrogen can have 4 bonds, just like real-life carbon. The same goes for giving "typographic" Carbon real-life oxygen qualities, etc. "Typographic" oxygen simply takes on the properties of the real-life noble gases in the comic (Helium, etc.), which form no bonds and are inert, just like "typographic" Oxygen is in the comic.<br />
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While the compound "ethynyl radical" with structure C-C-H has the formula C<sub>2</sub>H, there is no molecule with the C-H-C structure in nature. The word "mydrane" is a whimsical neologism for this fictional substance: the "hydr-" prefix for hydrogen is changed to "mydr-" (a prefix which does not exist) and combined to the "-ane" suffix for alkanes (simple H-C structures). Presumably, Randall has named this compound "Mydrane" to declare ownership of it ("My-" as in "mine"). Another reasonable assumption is that the word is a portmanteau of Methane (Me- is the prefix for 2 carbon chains) and Hydrogen with the -ane suffix for alkanes; the nomenclature stems from M(ethane) (h)ydr(ogen) -ane, which would form Mydrane.<br />
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The title text points out that the theory as presented only applies to sans-serif text. A {{w|serif}} is a small line across the end of each stroke. "<span style='font-family: "Liberation Serif", "Nimbus Roman No9 L Regular", Times, "Times New Roman", serif;'>H</span>", for instance, has four serifs, each with two leaf vertices. Thus hydrogen in a serif font would be able to form 8 bonds making it, according to the comic's theory, "more reactive". This would be the case with real atoms that have less than four valence electrons, as they would have more space for bonds to other atoms.<br />
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==Transcript==<br />
[The symbol for Hydrogen is shown.]<br />
<br />
Hydrogen can form four bonds. It readily bonds with itself, and often exists as a crystal.<br />
<br />
[A diagram with several 'H's is shown. The 'H's are connected in a pattern.]<br />
<br />
Crystalline Hydrogen<br />
<br />
[The symbol for Carbon is shown.]<br />
<br />
Carbon can only form two bonds. It readily bonds with Hydrogen to form C2H (Mydrane) or itself.<br />
<br />
[Two diagrams, one with two 'C's connected and one with two 'C's and an 'H' connected are shown.]<br />
<br />
[The symbol for Oxygen is shown.]<br />
<br />
Oxygen is inert, forming no bonds...<br />
<br />
[A diagram of several 'O's is shown. None are connected to anything.]<br />
<br />
Monoatomic Oxygen gas.<br />
<br />
Typographic Chemistry<br />
<br />
{{comic discussion}}</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=1442:_Chemistry&diff=782881442: Chemistry2014-11-04T14:40:33Z<p>141.101.104.143: </p>
<hr />
<div>{{comic<br />
| number = 1442<br />
| date = November 3, 2014<br />
| title = Chemistry<br />
| image = chemistry.png<br />
| titletext = These are all sans-serif compounds. Serif compounds are dramatically different and usually much more reactive.<br />
}}<br />
<br />
==Explanation==<br />
{{Incomplete|Rough draft. Need to explain the origin of "Mydrane" along with general improvements and proof reading.}}<br />
Chemical bonding is a well-known subject which explains the formation of {{w|molecule}}s from {{w|atom}}s. This comic refers to three {{w|chemical element}}s: Carbon (C), Hydrogen (H), and Oxygen (O). In real chemistry, the formation of bonds between atoms depends on the number of valence electrons each atom has, and how accessible those electrons are for bonding. The comic jokingly replaces valence electron theory with a theory that the number of bonds an atom can form depends on the number of {{w|Leaf vertex|leaf vertices}} possessed by the chemical symbol's letter. A leaf vertex is a vertex having only one edge connecting to one other vertex. "H" for example, the chemical symbol of Hydrogen, has 4 leaf vertices. This is shown in the comic by the four half-circles placed at each leaf vertex of the "H". Thus, in the comic's theory, elemental hydrogen can form 4 bonds. Oxygen, however, having the chemical symbol "O", has no leaf vertices, and according to the comic's theory should not bond to anything, and is therefore inert.<br />
<br />
Of course, the theory is completely inconsistent with observed chemistry. While the comic declares oxygen is inert and forms no bonds, this is not really the case: the two unpaired valence electrons in a lone oxygen atom makes oxygen reactive, and oxygen readily form molecules. Diatomic oxygen, O<sub>2</sub>, makes up about 20.9% of Earth's atmosphere, and is essential for aerobic life, including human life. Similarly, a water molecule consists of an oxygen atom tightly bonded to two hydrogen atoms.<br />
<br />
By observing real chemical compounds, chemists have deduced that hydrogen atoms really have 1 valence electron, carbon 4 and oxygen 6, allowing Hydrogen to have up to 1 bond, carbon up to 4, and oxygen up to 2. Thus it is Carbon which can have up to four bonds, and really is {{w|graphite|often found}} in {{w|diamond|crystalline form}} in nature (e.g., diamonds, coal); Oxygen which can have up to 2 bonds, and can combine with Carbon to form CO<sub>2</sub> (instead of C<sub>2</sub>H in the comic). We can see here that Randall is giving "typographic" Hydrogen real-life Carbon qualities, since "typographic" hydrogen can have 4 bonds, just like real-life carbon. The same goes for giving "typographic" Carbon real-life oxygen qualities, etc. "Typographic" oxygen simply takes on the properties of the real-life noble gases in the comic (Helium, etc.), which form no bonds and are inert, just like "typographic" Oxygen is in the comic.<br />
<br />
While the compound "ethynyl radical" with structure C-C-H has the formula C<sub>2</sub>H, there is no molecule with the C-H-C structure in nature. The word "mydrane" is a whimsical neologism for this fictional substance: the "hydr-" prefix for hydrogen is changed to "mydr-" (a prefix which does not exist) and combined to the "-ane" suffix for alkanes (simple H-C structures). Presumably, Randall has named this compound "Mydrane" to declare ownership of it ("My-" as in "mine"). Another reasonable assumption is that the word is a portmanteau of Methane (Me- is the prefix for 2 carbon chains) and Hydrogen with the -ane suffix for alkenes; the nomenclature stems from M(ethane) (h)ydr(ogen) -ane, which would form Mydrane.<br />
<br />
The title text points out that the theory as presented only applies to sans-serif text. A {{w|serif}} is a small line across the end of each stroke. "<span style='font-family: "Liberation Serif", "Nimbus Roman No9 L Regular", Times, "Times New Roman", serif;'>H</span>", for instance, has four serifs, each with two leaf vertices. Thus hydrogen in a serif font would be able to form 8 bonds making it, according to the comic's theory, "more reactive". This would be the case with real atoms that have less than four valence electrons, as they would have more space for bonds to other atoms.<br />
<br />
==Transcript==<br />
[The symbol for Hydrogen is shown.]<br />
<br />
Hydrogen can form four bonds. It readily bonds with itself, and often exists as a crystal.<br />
<br />
[A diagram with several 'H's is shown. The 'H's are connected in a pattern.]<br />
<br />
Crystalline Hydrogen<br />
<br />
[The symbol for Carbon is shown.]<br />
<br />
Carbon can only form two bonds. It readily bonds with Hydrogen to form C2H (Mydrane) or itself.<br />
<br />
[Two diagrams, one with two 'C's connected and one with two 'C's and an 'H' connected are shown.]<br />
<br />
[The symbol for Oxygen is shown.]<br />
<br />
Oxygen is inert, forming no bonds...<br />
<br />
[A diagram of several 'O's is shown. None are connected to anything.]<br />
<br />
Monoatomic Oxygen gas.<br />
<br />
Typographic Chemistry<br />
<br />
{{comic discussion}}</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=1402:_Harpoons&diff=727201402: Harpoons2014-08-01T17:41:28Z<p>141.101.104.143: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 1402<br />
| date = August 1, 2014<br />
| title = Harpoons<br />
| image = harpoons.png<br />
| titletext = To motivate it to fire its harpoons hard enough, Rosetta's Philae lander has been programmed to believe it is trying to kill the comet.<br />
}}<br />
<br />
==Explanation==<br />
The latter peak on this graph refers to the {{w|Rosetta (spacecraft)|Rosetta}} unmanned spacecraft. As part of its mission, it's carrying a lander (called {{w|Philae (spacecraft)|Philae}}), which has two tethers to anchor itself to the comet {{w|67P/Churyumov–Gerasimenko}}. Rosetta was launched in March 2004 (as shown in the graph) and is scheduled to encounter the comet in August 2014, making this a timely comic.<br />
<br />
The first peak is probably a joke. Officially, {{w|Apollo 12}} carried neither harpoons nor rum. However, as a former NASA contractor, Randall may know more about space shenanigans than the general public, and may be implying (perhaps jokingly) that a bottle of the [http://www.harpoon-rum.eu/1.html Harpoon] brand of {{w|Rum#Regional variations|Jamaican rum}} made it aboard.<br />
<br />
Possibly the 'harpoon' doubles here for 'harmonica' (as in "Me & Bobby McGee" by Janis Joplin: "... I pulled my harpoon out of my dirty red bandanna, // Playing soft while Bobby sang the blues ..."). Maybe someone had been wailin' a really bad tune up there.<br />
<br />
The caption implies that the spacecraft is sentient and believes that its mission is to kill the comet. This is (EDIT: Not) likely a parody of the novel ''{{w|Moby Dick}}'', in which Captain Ahab hunts a sperm whale named Moby Dick using traditional harpoons out of vengeance for the whale's biting off his leg.<br />
<br />
==Transcript==<br />
:'''Number of harpoons in space'''<br />
:by year<br />
:[A chart with a red graph is drawn below]<br />
:[The y-axis]<br />
:0 1 2 3<br />
:[The x-axis]<br />
:1950 1960 1970 1980 1990 2000 2010 2020<br />
:[The graph is at zero until a sharp peak to 1 in 1970. The peak is labeled]<br />
:Apollo 12 rum incident<br />
:[The graph then stays at 0 until 2004. Then it rises to 2 and stays there until today, continuing as a dotted line after 2014. The rise is labeled]<br />
:Rosetta comet mission launched carrying lander with harpoon tethers<br />
<br />
<br />
{{comic discussion}}</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=1402:_Harpoons&diff=727191402: Harpoons2014-08-01T17:40:40Z<p>141.101.104.143: /* Explanation */</p>
<hr />
<div>{{comic<br />
| number = 1402<br />
| date = August 1, 2014<br />
| title = Harpoons<br />
| image = harpoons.png<br />
| titletext = To motivate it to fire its harpoons hard enough, Rosetta's Philae lander has been programmed to believe it is trying to kill the comet.<br />
}}<br />
<br />
==Explanation==<br />
The latter peak on this graph refers to the {{w|Rosetta (spacecraft)|Rosetta}} unmanned spacecraft. As part of its mission, it's carrying a lander (called {{w|Philae (spacecraft)|Philae}}), which has two tethers to anchor itself to the comet {{w|67P/Churyumov–Gerasimenko}}. Rosetta was launched in March 2004 (as shown in the graph) and is scheduled to encounter the comet in August 2014, making this a timely comic.<br />
<br />
The first peak is probably a joke. Officially, {{w|Apollo 12}} carried neither harpoons nor rum. However, as a former NASA contractor, Randall may know more about space shenanigans than the general public, and may be implying (perhaps jokingly) that a bottle of the [http://www.harpoon-rum.eu/1.html Harpoon] brand of {{w|Rum#Regional variations|Jamaican rum}} made it aboard.<br />
<br />
Possibly the 'harpoon' doubles here for 'harmonica' (as in "Me & Bobby McGee" by Janis Joplin: "... I pulled my harpoon out of my dirty red bandanna, // Playing soft while Bobby sang the blues ...". Maybe someone had been wailin' a really bad tune up there.<br />
<br />
The caption implies that the spacecraft is sentient and believes that its mission is to kill the comet. This is (EDIT: Not) likely a parody of the novel ''{{w|Moby Dick}}'', in which Captain Ahab hunts a sperm whale named Moby Dick using traditional harpoons out of vengeance for the whale's biting off his leg.<br />
<br />
==Transcript==<br />
:'''Number of harpoons in space'''<br />
:by year<br />
:[A chart with a red graph is drawn below]<br />
:[The y-axis]<br />
:0 1 2 3<br />
:[The x-axis]<br />
:1950 1960 1970 1980 1990 2000 2010 2020<br />
:[The graph is at zero until a sharp peak to 1 in 1970. The peak is labeled]<br />
:Apollo 12 rum incident<br />
:[The graph then stays at 0 until 2004. Then it rises to 2 and stays there until today, continuing as a dotted line after 2014. The rise is labeled]<br />
:Rosetta comet mission launched carrying lander with harpoon tethers<br />
<br />
<br />
{{comic discussion}}</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=Talk:1402:_Harpoons&diff=72718Talk:1402: Harpoons2014-08-01T17:27:43Z<p>141.101.104.143: </p>
<hr />
<div>I took the sentient space craft joke to be a reference to the movie "Dark Star".<br />
<br />
Harpoon is a brand of rum. Did a bottle make it into space? [[Special:Contributions/108.162.219.196|108.162.219.196]] 12:55, 1 August 2014 (UTC)<br />
<br />
: I tried to find who makes it but wasn't able to find a definitive source. I added http://www.harpoon-rum.eu/ for now but it would be nice to have the link to the canonical source. Any pointers? --[[User:Waldir|Waldir]] ([[User talk:Waldir|talk]]) 17:24, 1 August 2014 (UTC)<br />
<br />
Did this comic upload quite late in the day for anyone else? Is anyone else experiencing or did anyone else experience that "Latest Comic" is still going to 1401 as ix XKCD.com and XKCD.com/#<br />
<br />
"This is obviously a joke, as sentient spacecraft cannot be created with current technology." Yeah, will need a citation on that... [[Special:Contributions/108.162.229.148|108.162.229.148]] 13:23, 1 August 2014 (UTC)<br />
<br />
Definitely a joke. Appolo 12’s call sign was Yankee Clipper, and a clipper ship would not carry any harpoons.[[Special:Contributions/108.162.216.129|108.162.216.129]] 14:04, 1 August 2014 (UTC)<br />
: I'd believe someone might have smuggled some Harpoon (or even any brand of) rum up there, then brought it back down with them, ingested or otherwise (thus the drop right after the mission). Alternately, "incident" could be something more along the lines of losing an empty bottle of rum during a spacewalk (farfetched as it may be) and it reentering the atmosphere(?) - probably no more than stories, though - nothing official probably exists about anything like that going up or down in any manner.<br />
<br />
<br />
Moby Dick is, let's say, extremely far-fetched. It was not the ship that was hunting the whale and harpooning it by itself. --[[Special:Contributions/141.101.104.143|141.101.104.143]] 17:27, 1 August 2014 (UTC)<br />
<br />
Could the Apollo 12 bump possibly be a reference to Futurama? "We're whalers on the moon, we carry a harpoon" [[Special:Contributions/199.27.130.246|199.27.130.246]] 15:51, 1 August 2014 (UTC)</div>141.101.104.143https://www.explainxkcd.com/wiki/index.php?title=Talk:1402:_Harpoons&diff=72703Talk:1402: Harpoons2014-08-01T15:16:27Z<p>141.101.104.143: </p>
<hr />
<div>I took the sentient space craft joke to be a reference to the movie "Dark Star".<br />
<br />
Harpoon is a brand of rum. Did a bottle make it into space? [[Special:Contributions/108.162.219.196|108.162.219.196]] 12:55, 1 August 2014 (UTC)<br />
<br />
Did this comic upload quite late in the day for anyone else? Is anyone else experiencing or did anyone else experience that "Latest Comic" is still going to 1401 as ix XKCD.com and XKCD.com/#<br />
<br />
"This is obviously a joke, as sentient spacecraft cannot be created with current technology." Yeah, will need a citation on that... [[Special:Contributions/108.162.229.148|108.162.229.148]] 13:23, 1 August 2014 (UTC)<br />
<br />
Definitely a joke. Appolo 12’s call sign was Yankee Clipper, and a clipper ship would not carry any harpoons.[[Special:Contributions/108.162.216.129|108.162.216.129]] 14:04, 1 August 2014 (UTC)<br />
: I'd believe someone might have smuggled some Harpoon (or even any brand of) rum up there, then brought it back down with them, ingested or otherwise (thus the drop right after the mission). Alternately, "incident" could be something more along the lines of losing an empty bottle of rum during a spacewalk (farfetched as it may be) and it reentering the atmosphere(?) - probably no more than stories, though - nothing official probably exists about anything like that going up or down in any manner.<br />
<br />
<br />
Moby Dick is, let's say, extremely far-fetched. It was not the ship that was hunting the whale and harpooning it by itself.</div>141.101.104.143