explain xkcd - User contributions [en]

2552: The Last Molecule

2021-12-09T07:37:49Z

ליאור: /* Explanation */ I'm a neurophotonics expert with a paper in Optica, and I can testify that the field is incomplete. For instance google 'Metamaterial cloaking' or 'Superlens'.

{{comic
| number = 2552
| date = December 8, 2021
| title = The Last Molecule
| image = the_last_molecule.png
| titletext = Biology is really struggling; they're barely at 93% and they keep finding more ants.
}}

==Explanation==
{{incomplete|Created by a FRUSTRATED BIOLOGIST - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

There are an infinite number of ways to arrange atoms into molecules, and chemistry is the study of the interaction of subatomic particles, atoms, and molecules, not simply the cataloging of all specimens of molecule.

This is reminiscent of biology's focus in previous centuries on simply cataloging the species on Earth.

Further, the goal of science is not to "complete" a field, but to understand it better and better. No scientific field is considered fully understood.

Putting Biology at 93% and Physics at 98% is patently absurd. As mentioned in the comic, we don't even know how many kinds of ants there are yet. When J.B.S Haldane, founder of the field of population genetics, was asked what could be inferred about the creator from the creation, he reportedly said, "He has an inordinate fondness for beetles". Insects aside, fundamental and important problems such as what genes promote which traits, the nature of cognition, and the mechanism behind several diseases remain complete mysteries. We know less about our own ocean floor than we do about the surface of Mars. Needless to say, Biology is nowhere close to 93% solved. As for Physics, questions such as "what the actual hell is dark matter?" and "how do we unify the four fundamental forces?" and "how do we make nuclear fusion possible on earth?" and "how fast does light travel in one direction?" make it clear that the field still has a long, long way to go.

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

[Ponytail is presenting on a stage. To the top-center of the slide displays "Chemistry" at a circled "100% complete", then to the left is "Biology" at "93% complete" and to the right is "Physics" at "98% complete". The bottom of the slide shows the [[Wikipedia:structural formula|structural formula]] of a molecule captioned "The last one", along with a few smaller captions around it drawn as squiggles.]

Ponytail:

:With the discovery of the last molecule, I'm pleased to announce that chemistry is finally complete.

:Best of luck to our competitors in their race for second place.

{{comic discussion}}

2365: Messaging Systems

2020-09-29T05:43:54Z

ליאור:

{{comic
| number = 2365
| date = September 28, 2020
| title = Messaging Systems
| image = messaging_systems.png
| titletext = SMS is just the worst, but I'm having trouble convincing people to adopt my preferred system, TLS IRC with a local server and a patched DOSBox gateway running in my mobile browser.
}}

==Explanation==
{{incomplete|Created by A VAGUELY MODERN SMS. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

Messaging systems suffer from the {{w|network effect}}, as in order to communicate, both parties need to be using the same system.
Though relatively ancient by modern standards, {{w|SMS}} is supported by almost every mobile device (unless you're using a [https://forward.com/news/157544/packing-stadium-for-anti-internet-message/ kosher mobile phone] or still on a {{w|DynaTAC}}) that has a phone number attached, which means if you want to send a message to someone, but aren't sure if you have a messaging protocol in common, you can be sure at least they have SMS.

The comic mentions many other communication systems, which offer various advantages in either security ({{w|end to end encryption}}) and or a bunch of general improvements filed under the label "vaguely modern", such as longer character limits and the ability to share media such as images in-service.

The title text proposes an alternative, absurd mingling of technologies in the vein of [[1636: XKCD Stack]]. IRC is Internet Relay Chat, a similarly antiquated messaging service that may also never die, as suggested in [[1782: Team Chat]]. DOSBox is an emulator that recreates the operating environment of {{w|MS-DOS}}.

Various other comics have referenced the issue of chat services, including [[1810: Chat Systems]], [[1254: Preferred Chat System]], and [[1782: Team Chat]].

=== Vaguely Modern ===
'''Slack'''
* {{w|Slack (software)|Slack}} is a workplace messaging service that offers the ability for administrators to create channels in order to organize the discussion. It is asynchronous, which means that conversations can occur out of time, hours apart from each other. It also keeps track of every message, and everything in a public channel stays there forever for everyone to see. It is not encrypted and has been moving towards being less privacy-focused for end-users over the years as corporate demand for employee surveillance has prompted the company to offer ever more invasive services to administrators. Overall, it is a popular service with some large companies and non-profit organisations but does not yet have universal adoption.

'''Facebook Messenger'''
* {{w|Facebook Messenger}} is {{w|Facebook}}'s messaging app for phones, but not everyone has a Facebook account, or uses Facebook regularly.

'''Hangouts'''
* {{w|Google Hangouts}} is a messaging service that can be accessed through the online Gmail client, as a separate web page and a standalone app for the phone. Theoretically, that means everybody has access to it, modern usage patterns mean that most people do not use the attached web client and don't bother downloading the app. It allows users to upload significantly degraded images, links, and other media along with text with a copy-paste.

'''Discord'''
* {{w|Discord (software)|Discord}} is an instant messaging and groups platform, initially designed for the gaming community, now being used by everyone.

'''Various DMs'''
* A {{w|Personal message|DM}} (direct message) is a private message between two or more users. The term DM originated from {{w|Twitter}}, but can be used for other "direct" messages from other social media or social messaging platforms.

=== Vaguely Modern & E2E Encrypted ===

'''Signal'''
*{{w|Signal (software)|Signal}} is an encrypted messaging service, popular among protesters and hackers who wish to remain anonymous. Signal allows for highly secure messaging and for messages to be deleted after a period of time.

'''iMessage'''
*{{w|iMessage}} is the instant messaging service for Apple devices. iMessage features end-to-end encryption; however, it only works between Apple devices, so users of Android devices are not able to receive or send messages through iMessage.

'''WhatsApp'''
*{{w|WhatsApp}} is a messaging service owned by Facebook. It has is popular in multiple countries, namely Latin America and India.

=== E2E Encrypted ===
{{w|End-to-end encryption}} is another messaging system where only the communicating users can read the messages posted. In principle, it prevents potential eavesdroppers – including {{w|telecom provider}}s, {{w|internet provider}}s, and even the provider of the communication service – from being able to access the {{w|cryptographic key}}s needed to decrypt the conversation.

'''PGP Email'''
*{{w|Pretty Good Privacy|PGP}} (short of "Pretty Good Privacy") is an encryption protocol for privacy and authentication developed in 1991. PGP can be used for signing, encrypting, and decrypting data. It is used to ensure the validity of the nature of the sender of the message (ie. to make sure you got the email from the sender and not from someone else pretending to be someone else with malicious intent). PGP was also featured in [[1181: PGP]].

'''Various Obscure Projects'''
*Randall is probably referring to the multitude of projects similar to those listed here that never went far.

'''Skype I Think'''
*{{w|Skype}} is a video conferencing service owned by Microsoft released in 2003; thus Randall does not consider Skype "modern". He is unsure if Skype is end-to-end encrypted or not.

'''Jabber + TLS'''
*Jabber (or {{w|XMPP}}) is a communications protocol based on XML that was developed in 1999. The Jabber protocol could be used with {{w|Transport Layer Security}} (TLS) to have a secure communications service.

=== Supported By Everyone ===
'''SMS'''
*{{w|SMS}} (short of Short Message Service) is a text-messaging service formally defined in the {{w|GSM}} standard in 1985 and first used in 1992. It limits messages to 160 characters, text-only. SMS has been extended by {{w|Multimedia Messaging Service|MMS}} (first used in 2002), which allows for "multimedia", including short videos, images and audio. MMS is also supported by most modern phones, but does not have any security features and is less powerful and less reliable than other messaging apps, making it less modern.

==Transcript==

A Venn Diagram is shown, framed in a box. It has three components:

Vaguely Modern, E2E Encrypted, Supported By Everyone

'''Items Solely in the Vaguely Modern category are:'''

:Facebook Messenger, Hangouts, Discord, Various DMs

'''Items In both 'Vaguely Modern' and 'E2E Encrypted' categories are:'''

:Signal, iMessage, Whatsapp

'''Items Solely in the E2E Encrypted category are:'''

:PGP Email, Various Obscure Projects, Skype I think, Jabber + TLS

'''Items Solely in the 'Supported By Everyone' category is:'''

:SMS

All other categories are empty.

[Caption below the comic]: Why SMS refuses to die

{{comic discussion}}
[[Category:Venn diagrams]]
[[Category:Phones]]
[[Category:Social networking]]

2365: Messaging Systems

2020-09-29T05:42:36Z

ליאור:

{{comic
| number = 2365
| date = September 28, 2020
| title = Messaging Systems
| image = messaging_systems.png
| titletext = SMS is just the worst, but I'm having trouble convincing people to adopt my preferred system, TLS IRC with a local server and a patched DOSBox gateway running in my mobile browser.
}}

==Explanation==
{{incomplete|Created by A VAGUELY MODERN SMS. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}

Messaging systems suffer from the {{w|network effect}}, as in order to communicate, both parties need to be using the same system.
Though relatively ancient by modern standards, {{w|SMS}} is supported by almost every mobile device (unless you're using a [https://forward.com/news/157544/packing-stadium-for-anti-internet-message/ kosher cell mobile] or still on a {{w|DynaTAC}}) that has a phone number attached, which means if you want to send a message to someone, but aren't sure if you have a messaging protocol in common, you can be sure at least they have SMS.

The comic mentions many other communication systems, which offer various advantages in either security ({{w|end to end encryption}}) and or a bunch of general improvements filed under the label "vaguely modern", such as longer character limits and the ability to share media such as images in-service.

The title text proposes an alternative, absurd mingling of technologies in the vein of [[1636: XKCD Stack]]. IRC is Internet Relay Chat, a similarly antiquated messaging service that may also never die, as suggested in [[1782: Team Chat]]. DOSBox is an emulator that recreates the operating environment of {{w|MS-DOS}}.

Various other comics have referenced the issue of chat services, including [[1810: Chat Systems]], [[1254: Preferred Chat System]], and [[1782: Team Chat]].

=== Vaguely Modern ===
'''Slack'''
* {{w|Slack (software)|Slack}} is a workplace messaging service that offers the ability for administrators to create channels in order to organize the discussion. It is asynchronous, which means that conversations can occur out of time, hours apart from each other. It also keeps track of every message, and everything in a public channel stays there forever for everyone to see. It is not encrypted and has been moving towards being less privacy-focused for end-users over the years as corporate demand for employee surveillance has prompted the company to offer ever more invasive services to administrators. Overall, it is a popular service with some large companies and non-profit organisations but does not yet have universal adoption.

'''Facebook Messenger'''
* {{w|Facebook Messenger}} is {{w|Facebook}}'s messaging app for phones, but not everyone has a Facebook account, or uses Facebook regularly.

'''Hangouts'''
* {{w|Google Hangouts}} is a messaging service that can be accessed through the online Gmail client, as a separate web page and a standalone app for the phone. Theoretically, that means everybody has access to it, modern usage patterns mean that most people do not use the attached web client and don't bother downloading the app. It allows users to upload significantly degraded images, links, and other media along with text with a copy-paste.

'''Discord'''
* {{w|Discord (software)|Discord}} is an instant messaging and groups platform, initially designed for the gaming community, now being used by everyone.

'''Various DMs'''
* A {{w|Personal message|DM}} (direct message) is a private message between two or more users. The term DM originated from {{w|Twitter}}, but can be used for other "direct" messages from other social media or social messaging platforms.

=== Vaguely Modern & E2E Encrypted ===

'''Signal'''
*{{w|Signal (software)|Signal}} is an encrypted messaging service, popular among protesters and hackers who wish to remain anonymous. Signal allows for highly secure messaging and for messages to be deleted after a period of time.

'''iMessage'''
*{{w|iMessage}} is the instant messaging service for Apple devices. iMessage features end-to-end encryption; however, it only works between Apple devices, so users of Android devices are not able to receive or send messages through iMessage.

'''WhatsApp'''
*{{w|WhatsApp}} is a messaging service owned by Facebook. It has is popular in multiple countries, namely Latin America and India.

=== E2E Encrypted ===
{{w|End-to-end encryption}} is another messaging system where only the communicating users can read the messages posted. In principle, it prevents potential eavesdroppers – including {{w|telecom provider}}s, {{w|internet provider}}s, and even the provider of the communication service – from being able to access the {{w|cryptographic key}}s needed to decrypt the conversation.

'''PGP Email'''
*{{w|Pretty Good Privacy|PGP}} (short of "Pretty Good Privacy") is an encryption protocol for privacy and authentication developed in 1991. PGP can be used for signing, encrypting, and decrypting data. It is used to ensure the validity of the nature of the sender of the message (ie. to make sure you got the email from the sender and not from someone else pretending to be someone else with malicious intent). PGP was also featured in [[1181: PGP]].

'''Various Obscure Projects'''
*Randall is probably referring to the multitude of projects similar to those listed here that never went far.

'''Skype I Think'''
*{{w|Skype}} is a video conferencing service owned by Microsoft released in 2003; thus Randall does not consider Skype "modern". He is unsure if Skype is end-to-end encrypted or not.

'''Jabber + TLS'''
*Jabber (or {{w|XMPP}}) is a communications protocol based on XML that was developed in 1999. The Jabber protocol could be used with {{w|Transport Layer Security}} (TLS) to have a secure communications service.

=== Supported By Everyone ===
'''SMS'''
*{{w|SMS}} (short of Short Message Service) is a text-messaging service formally defined in the {{w|GSM}} standard in 1985 and first used in 1992. It limits messages to 160 characters, text-only. SMS has been extended by {{w|Multimedia Messaging Service|MMS}} (first used in 2002), which allows for "multimedia", including short videos, images and audio. MMS is also supported by most modern phones, but does not have any security features and is less powerful and less reliable than other messaging apps, making it less modern.

==Transcript==

A Venn Diagram is shown, framed in a box. It has three components:

Vaguely Modern, E2E Encrypted, Supported By Everyone

'''Items Solely in the Vaguely Modern category are:'''

:Facebook Messenger, Hangouts, Discord, Various DMs

'''Items In both 'Vaguely Modern' and 'E2E Encrypted' categories are:'''

:Signal, iMessage, Whatsapp

'''Items Solely in the E2E Encrypted category are:'''

:PGP Email, Various Obscure Projects, Skype I think, Jabber + TLS

'''Items Solely in the 'Supported By Everyone' category is:'''

:SMS

All other categories are empty.

[Caption below the comic]: Why SMS refuses to die

{{comic discussion}}
[[Category:Venn diagrams]]
[[Category:Phones]]
[[Category:Social networking]]

2345: Wish on a Shooting Star

2020-08-13T10:20:22Z

ליאור: + {{w|Perseids}} meteor shower

{{comic
| number = 2345
| date = August 12, 2020
| title = Wish on a Shooting Star
| image = wish_on_a_shooting_star.png
| titletext = Congratulations to whoever wished for revenge on a forest near the Tunguska River, a 1980 Chevy Malibu in Peekskill NY, Alabama resident Ann Hodges, every building in Chelyabinsk with glass windows, and the non-avian dinosaurs.
}}

==Explanation==
{{incomplete|Created by a NON-AVIAN DINOSAUR HATER. Please mention here why this explanation isn't complete. Do NOT delete this tag too soon.}}
This comic was published at the annual peak of the {{w|Perseids}} {{w|meteor shower}}. It is a common practice to make a wish when one sees a shooting star, in hopes that the wish comes true. This comic consists of a [[:Category:Venn diagrams|Venn diagram]] showing what things are commonly wished for upon seeing a shooting star, and what things the shooting star may cause. Shooting stars, as they are actually meteors, can only cause changes to physical phenomena, such as radio noise or the appearance of the sky as they burn up in the upper atmosphere. The only thing that is shared between the potential wish side of the diagram and the shooting star caused side is revenge. This would occur when a shooting star actually hits the planet, becoming a meteorite. This is frequently highly destructive, given the high speed of falling meteors. As such, it would be possible for the meteorite to hit something that someone for some reason or another wished revenge upon. However, given the massive surface area of the planet, the likelihood that someone's revenge would be "granted" by a meteorite would be very low. The title text makes fun of this by detailing several incidents where a meteorite landed and caused damage.

List of things that were damaged by meteors (from title text):
* On June 30, 1908 ({{w|Gregorian Calendar}}, Russia still used Julian and was recorded there as June 17), an {{w|airburst}} caused by the {{w|Tunguska Event|breakup of a 100-meter falling meteorite or comet}} with the energy of some 30 megatons of {{w|TNT}} flattened some 80 million trees over 830 square miles (2,150 km<sup>2</sup>) of land in central {{w|Siberia}} near the {{w|Podkamennaya Tunguska|Tunguska River}}. Due to the remoteness of the area, no people were confirmed dead in the incident.
* On October 9, 1992, a meteorite {{w|Peekskill meteorite|damaged a 1980 Chevrolet Malibu in Peekskill, New York}}.
* On November 30, 1954, a {{w|Sylacauga (meteorite)|fragment of a meteorite}} passed through the roof of a house and struck a woman named Ann Hodges. She survived.
* On February 15, 2013, a meteorite {{w|Chelyabinsk meteor|exploded in an airburst}} over Chelyabinsk, Russia, creating a shockwave that shattered windows in the area.
* The {{w|Cretaceous–Paleogene extinction event|extinction of the dinosaurs}} around 65 million years ago is believed to be caused by an {{w|Alvarez hypothesis|impact of a comet or asteroid}}. Randall mentions "non-avian" dinosaurs, as birds are descendants of dinosaurs, though they are not commonly thought of as dinosaurs.

Meteorites were most recently mentioned in [[2328: Space Basketball]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[A Venn diagram is shown:]

:[The left circle is labeled "Things people wish for" and contains:]
:Love
:Money
:Fame
:Health
:Power
:Luck
:Success

:[The right circle is labeled "Things shooting stars can cause" and contains:]
:Radio noise
:Dust and ionized gas in the upper atmosphere
:Infrasound
:Cool lights in the sky

:[The only item in the overlapping section is:]
:Revenge

{{comic discussion}}
[[Category:Astronomy]]
[[Category:Venn diagrams]]
[[Category:Comics featuring real people]]

1940: The Food Size Cycle

2018-01-11T13:57:44Z

ליאור: /* Explanation */ Hertzsprung–Russell diagram

{{comic
| number = 1940
| date = January 10, 2018
| title = The Food Size Cycle
| image = the_food_size_cycle.png
| titletext = There's data suggesting that this model may apply to deep-dish/thin-crust pizza. I've designed a thorough multi-year study to investigate this personally, but funding organizations keep denying my grant requests.
}}

==Explanation==
{{incomplete|Explanation needs expansion. Do NOT delete this tag too soon.}}
This comic illustrates the evolution of the size of food items over time, using the example of a sandwich. It starts with a regular sandwich at the beginning. As the sandwich became more popular, sandwich makers had an {{w|arms race}} concerning sandwich size as they competed for customers. Eventually, these sandwiches became too big to eat comfortably. At this point (according to Randall) some smart guy invented the panini, a small sandwich, to cater to those who couldn't find a sandwich small enough for their needs. Eventually, the panini itself will begin to grow, and either displace or become indistinguishable from the existing giant sandwiches, and the cycle will repeat.

The diagram and the diagonal trace across it alludes to [https://en.wikipedia.org/wiki/Hertzsprung%E2%80%93Russell_diagram Hertzsprung–Russell diagrams] of [https://en.wikipedia.org/wiki/Main_sequence Main sequence] stars.

The title text suggests that the same cycle may be applicable to the depth of pizza crust, with thin crusts being replaced with deeper and deeper ones, eventually necessitating a resurgence in thin crust. Randall laments that despite seeking funding to conduct experiments to test that hypothesis, he keeps getting turned down, probably because it sounds suspiciously like he wants to be paid for eating pizza.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:'''The food size cycle'''

:[There is a chart, with the x axis labeled "Food item size", and y labeled "Time". The arrows are pointing away from the top left corner.]

:[A normal sandwich is shown high up the chart.]

:Initial normal-sized food (sandwich, burger, burrito, taco, etc)

:Food becomes more popular

:[A larger sandwich is shown.]

:[An even larger sandwich is shown.]

:Size arms race: average item grows as restaurants compete to offer the largest version to hungry customers

:[An enormously large sandwich is shown.]

:Food gets too large to eat comfortably

:[On the left side of the second largest sandwich:]

:Void

:[A new row comes up, inside is a panini.]

:New format appears and fills the void (panini, burrito bowl, taquito, slider, etc)

:[The two paths are converging.]

:Merger or replacement

{{comic discussion}}

[[Category:Charts]]
[[Category:Food]]