explain xkcd - User contributions [en]

2347: Dependency

2020-08-25T02:40:52Z

173.245.54.187: /* Background and Examples */ fix copy; we want "so that" here, not "such that".

{{comic
| number = 2347
| date = August 17, 2020
| title = Dependency
| image = dependency.png
| titletext = Someday ImageMagick will finally break for good and we'll have a long period of scrambling as we try to reassemble civilization from the rubble.
}}

==Explanation==
{{incomplete|Created by A PROJECT [[User:Dgbrt|SOME RANDOM PERSON]] HAS BEEN THANKLESSLY MAINTAINING SINCE 2003
. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

Technology architecture is often illustrated by a stack diagram [https://www.guru99.com/images/1/102219_1135_TCPIPvsOSIM1.png], in which higher levels of rectangles indicate components that are dependent on components in lower levels. This is analogous to a physical tower of blocks, in which higher blocks rest on lower blocks. The stack in this cartoon bears a striking resemblance to a physical block tower, suggesting the danger that the tower will lose its balance when a critical piece is removed, in this case a piece near the bottom, labeled as being maintained by a single semi-anonymous person located somewhere relatively unimportant doing it for their own unknown reasons without fame or acknowledgement. The concept of balance is not intended to be communicated by a stack diagram, making this a humorously absurd extension of a well-known diagram style.

{{w|ImageMagick}}, mentioned in the title text, is a popular, standalone utility released in 1990 that is used for performing transformations between various graphics file formats, and various other transformations. While there are also numerous libraries and API's for performing these tasks within larger programs, ImageMagick is so popular and easy to use that many programs use its API or just find it easier to {{w|Shell (computing)#Other uses|shell out}} to ImageMagick to perform a necessary transformation. They therefore {{w|Dependency hell|depend}} on ImageMagick, and would break if ImageMagick were to disappear.

===Background and Examples===
Taking code re-usability and modularization to its logical extreme has been a long-time tenet for programmers; programming began as a slow task on very memory-constrained systems, utilizing punch cards and days of delay waiting to discover a bug, so that reuse made things possible that otherwise wouldn't be. Once systems became small, fast, and able to hold a lot of data, the ability to provide higher and higher degrees of automation made reusable libraries a huge engine behind the development of technology. By outsourcing what would seem like basic functions, such as string manipulation, to other libraries, developers waste less time reinventing the wheel, so the philosophy goes, and thus many tiny packages, many of which contained only one function, became popular dependencies. This was especially true in Unix and Linux, where an entire program is commonly used for one small task, and programs exist to tie others together into powerful shell scripts.

Node.js (a breed of JavaScript) and Python are two modern ecosystems providing huge stashes of centralized libraries where developers of the world can come together to stand on the shoulders of all the small useful libraries they make for each other, to make new ones that are more and more powerful, and also more and more prone to sudden new unexpected bugs somewhere in the dependency chain. JavaScript was designed to be an easy to use front end scripting language, not a basic and core backend language as users of node.js's {{w|npm (software)|NPM}} package manager have made it be. While in theory, such a system may sound good for developers who would need to write and maintain fewer lines of code, systems which are highly optimized are also highly susceptible to rapid changes. For example, the famous left-pad incident in the NPM package manager left many major and minor web services which depended on it unable to build. A disgruntled developer unpublishing 11 lines of code was able to break everybody's build, because everyone was using it. [https://www.theregister.com/2016/03/23/npm_left_pad_chaos/]

In 2014, the {{w|Heartbleed|Heartbleed bug}} revealed a significant portion of the internet was vulnerable to attack due to a bug in OpenSSL, a free and open-source library facilitating secure communication. One headline at the time demonstrated this comic in real life: "The Internet is Being Protected by Two Guys Named Steve" [https://www.buzzfeed.com/chrisstokelwalker/the-internet-is-being-protected-by-two-guys-named-st]. The aforementioned Steves were overworked, underfunded, and largely unknown volunteers whose efforts nevertheless underpinned the security of major websites throughout the world. Randall provided a concise, helpful explanation of the bug in [[1354: Heartbleed Explanation]].

The current model of libraries and open-source development (topics which Randall has addressed extensively in the past) relies heavily on the free and continued dedication of unpaid hobbyists. Though some major projects such as Linux may be able to garner enough attention to build an organization, many smaller projects, which are in turn reused by larger projects, may only be maintained by one person, either the founder or another who has taken the torch. Maintaining libraries requires both extensive knowledge of the library itself as well as any use cases and the broader community around it, which usually is suited for maintainers who have spent years at the task, and thus cannot be easily replaced. Thus, there are many abandoned projects on the internet as people move on to greener pastures. Far from the days of backwards compatibility, that's usually not a problem, unless a project happens to be far up the dependency chain, as illustrated, in which case there may be a crisis down the road for both the developers and the users down the chain.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A tower of blocks is shown. The upper half consists of many tiny blocks balanced on top of one another to form smaller towers, labeled:]

All modern digital infrastructure

[The blocks rest on larger blocks lower down in the image, finally on a single large block. This is balanced on top of a set of blocks on the left, and on the right, a single tiny block placed on its side. This one is labeled:]

A project some random person in Nebraska has been thanklessly maintaining since 2003

{{comic discussion}}
[[Category: Programming]]

Talk:2321: Low-Background Metal

2020-06-19T18:08:00Z

173.245.54.187:

Spoiler Alert for Avengers Endgame next comment [[Special:Contributions/162.158.75.60|162.158.75.60]] 20:36, 18 June 2020 (UTC)
:I can't help but notice that the basic premise of this comic is very much like the reason for going back to 1970 in ''Avengers: Endgame'', when they needed more Pym particles for time travel. I wonder if Randall re-watched it again recently? — [[User:KarMann|KarMann]] ([[User talk:KarMann|talk]]) 17:10, 17 June 2020 (UTC)
:: Whoa! Spoiler alert! Disney Plus won't have Infinity War until next week. I'm not watching them out of order! [[User:Mathmannix|Mathmannix]] ([[User talk:Mathmannix|talk]]) 12:16, 18 June 2020 (UTC)

Oh, that's new to me, that they use roman ships to get to higher quantities of lead. For Steel they use German ships. after world war I, the german high seas fleet was captured and put under arrest in scottish waters. To not allow the enemy to utilize the ships, they all sank themselfes. {{w|Scuttling_of_the_German_fleet_at_Scapa_Flow|wikisource}} --[[User:Lupo|Lupo]] ([[User talk:Lupo|talk]]) 05:46, 18 June 2020 (UTC)

Is there any evidence of Roman ships using lead for ballast? I know it was used as a structural metal and utility metal (sheathing, seam sealing, anchors, tools). It was also carried as cargo. But it seems likely that Roman lead was too expensive to be used as ballast, particularly compared to, say, rocks or concrete. (Note that loading cargo low in the hull is not ballast, cargo is there because you want to move it, ballast is there only to keep the boat upright.)[[Special:Contributions/173.245.54.187|173.245.54.187]] 18:08, 19 June 2020 (UTC)

== Drawing ==

There's one leg of the time-machine missing from the 3rd panel. (or is it the side of a base?) --[[Special:Contributions/162.158.155.126|162.158.155.126]] 19:57, 17 June 2020 (UTC)

== Mined lead ==

Pb-210 (half-life 20.4 years) is a decay product of radon, and thus accumulates everywhere that is exposed to the atmosphere or where radon seeps from the ground. I suspect it could be a contaminant in lead from some lead mines, but wasn't able to find any references [[User:ShadwellNH|ShadwellNH]] ([[User talk:ShadwellNH|talk]]) 20:00, 17 June 2020 (UTC) Paul

== One use only? ==

The way I understand it, the time machine is one-use unless you find other Low-Background Metal. If you find it, you can make more trips. It would appear that the trip is successful.
--[[Special:Contributions/188.114.103.129|188.114.103.129]] 01:31, 18 June 2020 (UTC)

So you'd say a car is also one-use, unless you find a gas station? [[Special:Contributions/162.158.158.167|162.158.158.167]] 08:51, 18 June 2020 (UTC)

::::(out of chrono... I am 162.158.158.167): No, I'd say that this is not a one-use time machine, so it's wrong to compare it to one-use time machines. Luckily, someone else changed the text already. --[[Special:Contributions/188.114.102.22|188.114.102.22]] 13:39, 19 June 2020 (UTC)

: No, but if the parts it was made of had to be replaced after every trip, I definitely would. [[Special:Contributions/172.69.70.117|172.69.70.117]] 16:59, 18 June 2020 (UTC)

:: Sure, but the ability to rebuild the car with completely new material doesn't turn it into a multi-use car. [[Special:Contributions/141.101.98.130|141.101.98.130]] 04:11, 19 June 2020 (UTC)

== Real life use of this lead? ==

Does anyone know whether there is any truth whatsoever to scientists using lead from sunken ships to shield delicate equipment? Obviously not time machines, but there are some pieces of equipment that might be sensitive to radiation.

Also, would lead that was in the ocean actually be safer from nuclear fallout than lead that was underground and mined after the nuclear testing ended? [[Special:Contributions/108.162.216.172|108.162.216.172]] 03:31, 18 June 2020 (UTC)
: Yes. At least it is done with steel. [https://hackaday.com/2017/03/27/low-background-steel-so-hot-right-now/][https://www.good.is/articles/the-search-for-low-background-steel][https://www.stainless-steel-world.net/mobile/webarticles/joanne-mcintyre/disappearing-warships-scavengers-raid-war-graves-for-low-background-steel.html] [[Special:Contributions/172.69.33.129|172.69.33.129]] 04:50, 18 June 2020 (UTC)

:Yes the water is a better insulator than air. Also the fallout would be partially absorbed by plants/animals before reaching the ocean bottom. [[Special:Contributions/162.158.123.155|162.158.123.155]] 16:51, 19 June 2020 (UTC)

: Low Background Lead is also used, mentioned in the Good article. The equipment that need this stuff is mostly radiation sensors, very precise ones that can detect even smallest amounts of radiation. And for the last Question, you can't find pure natural lead, its mostly contaminated with radioactive elements (most lead in the universe results from decay chains). And common lead is made through recycling. Ancient lead from roman ships had enough time for the radioactive elements to decay into stable lead. --[[Special:Contributions/141.101.105.114|141.101.105.114]] 06:12, 18 June 2020 (UTC)

== May be complicated ==

The 1968 Story [https://scifi.stackexchange.com/questions/109243/modern-military-jet-goes-back-to-world-war-i Hawk among Sparrows] discusses the problems modern war hardware may have when used against old tech. -- [[Special:Contributions/141.101.76.82|141.101.76.82]] 07:39, 18 June 2020 (UTC)
: This was also part of the premise of the 1980 movie "Final Countdown", when the aircraft carrier Nimitz shows up in the Pacific Ocean on December 6, 1941. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 13:38, 18 June 2020 (UTC)
: {{w|Biggles_(film)|Biggles: The Movie}} had a WW1 flying ace ''take'' a 1980s helicopter (ostensibly unarmed, except fortuitously/inevitably against the Big Bad Weapon) back to his era, thanks to a Time-Twin plotline. Thus, IIRC it only did well to defend against era-local aicraft by the mythical skill of the eponymous pilot, and was handily lost once the temporal-trickery job was finally accomplished. If you enjoy that era of kitcsh then I'd suggest you not pass up a viewing, even if not actually seek it out. [[Special:Contributions/141.101.98.130|141.101.98.130]] 17:11, 18 June 2020 (UTC)
* I am also mildly disappointed that the helicopter is not Airwolf. [[User:Nutster|Nutster]] ([[User talk:Nutster|talk]]) 03:11, 19 June 2020 (UTC)

== Safer alternative? ==

They could just send a cache of modern lead back in time and wait till it cools down. [[Special:Contributions/141.101.76.82|141.101.76.82]] 06:30, 19 June 2020 (UTC)
Naah, that would totally violate causality. Not to mention that you'd now have the exact same atoms existing in two spatial places at the same time. That could quite easily lead to the Earth being engulfed in a giant wormhole. [[User:Cellocgw|Cellocgw]] ([[User talk:Cellocgw|talk]]) 10:05, 19 June 2020 (UTC)

== Add Topic ==

Can we Add Topic with impunity now?
WOOOPEEEE![[Special:Contributions/108.162.216.216|108.162.216.216]] 10:45, 19 June 2020 (UTC)[[Special:Contributions/108.162.216.216|108.162.216.216]] 10:48, 19 June 2020 (UTC)

446: In Popular Culture

2014-11-07T01:17:15Z

173.245.54.187: wood in popular culture, reference added

{{comic
| number = 446
| date = July 7, 2008
| title = In Popular Culture
| image = in_popular_culture.png
| titletext = Someday, the 'in popular culture' section will have its own article with an 'in popular culture' section. It will reference this title-text referencing it, and the blogosphere will implode.
}}

==Explanation==
Wikipedia is a popular online encyclopedia with articles that are created and edited by the general public. Wikipedia entries have many sections, with the first few explaining the general concept and details behind the subject. Its called wood because [http://www.xvideos.com/video6535590/super_cute_teen_gets_a_creampie long, hard wood goes in your pussy].

When this comic was written many Wikipedia articles had a section at the end entitled "in popular culture", listing TV shows, movies, songs and so on which made reference to the subject at hand. In many cases, this list was extensive, possibly because the people editing the articles were such fans of the subject or the pop culture in which it is referenced, they couldn't help but go into great detail, listing many esoteric and seemingly irrelevant elements of pop culture which were peripherally related to the subject of the article. As an example, see the old article [https://en.wikipedia.org/w/index.php?title=Apollo_in_popular_culture&oldid=153446837 Apollo in popular culture] which as of August 2007 redirects to {{w|Apollo}}.

The joke in this case is that even such a mundane article such as one on wood could have an "in popular culture" section and obviously, wooden items are common enough that there are any number of instances of popular culture which could be considered to "reference it", even if that's something as basic as a wooden item being used as a prop in a TV show. Such information would be of little or no use to anybody and only somebody obsessed with wood, a particular element of pop culture in which wood makes an appearance or the concept of placing pop culture references in encyclopedia articles would bother to create or maintain such a section.

Also, wood being such a popular material, the list of references could be virtually endless. This is a reference to the fact that the "in popular culture" sections of many Wikipedia articles contained dozens of items, even for articles on fairly arcane subjects. Note that the end of this particular "in popular culture" section is not visible so we don't know how long it is.

The title text states that in the future there will even have to be a wiki page with the subject "In popular culture". This article will also need an "in popular culture" section and it will be obvious to make a reference directly to this title text, as xkcd is part of popular culture and because this title text predicted the creation of and need for such a page. However this would then create a circular reference. This could be considered a form of infinite loop which is one way to cause a computer to crash (lock up). The joke is that the blogosphere could follow this endless train of circular links and itself crash, causing an "implosion".

This comic was mentioned in {{w|Wikipedia:"In popular culture" content}}. However, on April 23, 2014, the reference was edited out. It has since been re-added under the external links section.

==Transcript==
:[A fictional screen capture of the Wikipedia article for "wood" is shown.]
:'''Wood''' is a hard, fibrous tissue found in many plants. It has been used for centuries for both fuel and as a construction material for... [cut in page.]
:In popular culture:
:In episode 6 of ''Firefly'', "''Our Mrs. Reynolds''," Jayne is given a wooden rain stick by a villager.
:In the Buffyverse, Buffy often slays Vampires using stakes made of wood.
:The wand used by Harry Potter is made of wood from a holly tree.
:The fence around the back yard of the house in ''The Simpsons'' is wooden.
:In the 2004 TV series ''Battlestar Galactica'' [rest of page is cut.]

{{comic discussion}}
[[Category:Wikipedia]]
[[Category:Comics with color]]

1079: United Shapes

2014-07-27T23:42:48Z

173.245.54.187: North and South Dakota are also paired, like Alabama and Mississippi and Georgia and Missouri.

{{comic
| number = 1079
| date = July 9, 2012
| title = United Shapes
| image = united_shapes.png
| imagesize = 800px
| titletext = That eggplant is in something of a flaccid state.
}}

==Explanation==
{{incomplete|This explain doesn't explain the content of this comic.}}

In this comic, each state of the United States of America has been filled-in with an object of similar shape. Due to the size range of the states, some states are too small to clearly make-out in the normal size image. Click on the image above to see the large version, which makes every state perfectly clear.

Very few, if any, of the shapes used are stereotypes of the state; they are merely objects that look like the state. Some of the objects are those which the states are widely known to resemble. For example, Michigan is represented by a mitten or glove, and a pot with handle takes the place of Oklahoma (with the panhandle region of the state filled with a literal handle). Others, however, are more creative. Few would have likely pictured Texas as a dog or Alaska as a bear with a jet pack and laser gun. There are several incredibly simple objects filling some states. Kentucky is filled by a cloud, which conceivably could have been used for any state, and Wyoming, one of the square states, is simply an envelope. There are three pairs of states that are related. Georgia and Missouri each contain an image of the other,drawing attention to their similar shapes, North and South Dakota are the top and bottom halves of an amp, and Alabama and Mississippi are faces facing in opposite directions.

Colorado contains what looks like a Wikipedia article. A close-up of the fake article is provided [http://xkcd.com/1079/colorado/]. The following references are made in the Colorado article:

*The pronunciation is not that for Colorado, but for {{w|Eyjafjallajökull}}, a volcano in Iceland that erupted in April 2010.
*The way it has a demilitarized zone towards Wyoming resembles {{W|North Korea}} and {{W|South Korea}}. As the two US states are both almost square and borders each other in a way similar to Korea this makes sense. Although here it is the southern part (Colorado) that sound like North Korea.
*Eleven dimensions refers to {{w|string theory}}.
*A {{w|wormhole}} is a theoretical relative of the {{w|black hole}}. This is a reference to the television series {{w|Stargate SG-1}} where a device capable of creating wormholes is located in the {{w|Cheyenne Mountain nuclear bunker}} in Colorado.
*A {{w|Horcrux}} is a type of magical object in the world of {{W|Harry Potter}}.
*The radiation zones around Longmont are caused by {{w|Radioactive contamination from the Rocky Flats Plant|radioactive contamination from the Rocky Flats Plant}}.

The title text makes fun of Florida which is sometimes called "The penis of America". Obviously, this penis is somewhat flaccid (not erect). The use of the word "state" is a pun, as it means some particular condition (flaccid state) as well as a political entity (The State of Florida).

==Transcript==
:The '''United Shapes'''
:A map of things states are shaped like
:[Each state has some item wedged to stay inside its borders]

:Alabama: A moai head facing east.
:Alaska: Winnie the Pooh with a jetpack and a ray gun.
:Arizona: A refrigerated shelf containing milk, bread, and pastries.
:Arkansas: A measuring cup.
:California: A vacuum.
:Colorado: The wiki article on Colorado.
:Connecticut: A train conductor's hat.
:Delaware: A meerkat.
:Florida: An eggplant.
:Georgia: Missouri.
:Hawaii: A snowball.
:Idaho: A garden gnome, sitting down.
:Illinois: A gangster with a guitar case, upside down.
:Indiana: The brush of a paintbrush.
:Iowa: A tomato, lettuce, cold cut and cheese sandwich.
:Kansas: A stand-up piano.
:Kentucky: A cloud.
:Louisiana: A boot with some gum stuck to the bottom of it.
:Maine: A Vulcan salute.
:Maryland: A howling wolf, upside down.
:Massachusetts: An elephant, being ridden by a man, carrying tea.
:Michigan: A mitten for the lower portion, an eagle for the UP.
:Minnesota: $160 in $20 USD bills.
:Mississippi: A moai head facing west.
:Missouri: Georgia.
:Montana: One half of a muffin.
:Nebraska: A blue VW type 2 with mattresses sticking out the back.
:Nevada: A clothes iron.
:New Hampshire: A tall brick factory building.
:New Jersey: A bent-over old person.
:New Mexico: A liquid container labeled for something of unusual and silly danger.
:New York: A hybrid transmission with standard manual-style gears and a torque converter sliced in half.
:North Carolina: A bouquet of flowers.
:North Dakota: The top half of an amp.
:Ohio: Underwear (Briefs).
:Oklahoma: A covered pot, dripping with boilover.
:Oregon: A locomotive.
:Pennsylvania: A very thick book with a bookmark.
:Rhode Island: The bow half of a boat's hull.
:South Carolina: A slice of pizza.
:South Dakota: The bottom half of an amp.
:Tennessee: A number of childrens' books, placed in a slightly askew pile.
:Texas: A dog sitting in a bowl.
:Utah: An oven.
:Vermont: A microscope, upside down.
:Virgina: A stegosaurid.
:Washington: A whale.
:West Virginia: A frog.
:Wisconsin: A skull.
:Wyoming: An envelope.

{{comic discussion}}
[[Category:Large drawings]]
[[Category:Comics with color]]