YouTube

YouTube is a video sharing website currently owned by Google. YouTube is currently the most popular video hosting website on Earth.
== Archive Team project ==
Archive Team launched a project to archive certain videos and channels from YouTube. Videos archived in this project are ingested into the Wayback Machine, and will be playable in the Wayback Machine (WBM) after being added to a separate index (may take a few days). Note: YouTube includes your worker's IP address in the videoplayback urls. As such, your worker's IP will be recorded in the project's data.
=== Scope ===
Anyone is able to queue channels and videos to be archived in channel . However, the videos and channels to be archived should be limited to:
* Channels/videos almost sure to be deleted, like:
** Company gone bankrupt
** Person died
** YouTube banning certain channels/content
* The following channels/videos if they are connected to a major event that could cause them to be changed heavily or deleted:
** Government channels
** News channels
** Event channels
** Political party channels
** Politician accounts
* Unlisted videos (hidden from YouTube search, only accessible by URL)
* Advertisement video that YouTube actually treats as advertisement
* 'Newsworthy' content, for example:
** Channels/videos from opinion makers in the Russia-Ukraine war
** Channels/videos containing content of major events (terror attacks, wars, etc.)
*** Only queue an entire channel if the entire channel is related to the major event.
* Others are possible, check in with Arkiver on IRC.
When a channel of video is queued for archival, a reason should be given with -e/--explain.
== Why download? ==
Just like local backups, it is advisable to download videos regularly, as any which is not backed up is hanging by a thread above the memory hole. Even downloading at a low resolution such as 240p or 360p still is infinitely better than nothing (0p).
While established platforms typically have a solid and failure-resistant technical infrastructure, any content is still endangered from human factors. Not only could a creator run afoul of YouTube's site staff (or any other platform for that matter), or the platform change their policies in a way that affects existing content retroactively, but a creator themselves might run into public controversity and according scrutiny, or emotionally decide that they no longer like some of their early videos, and as eternal as they once appeared, they are gone in a flash, or locked away in the vault of private videos.
Video creators are recommended to upload their work to no less than two platforms. If platform staff decides take down videos or even nuke an entire channel, which is done with the press of a button and takes an entire stash of videos with it, viewers will know where to still find those videos.
:"Google [parent company of YouTube] is an archive in the same way a supermarket is a food museum." –– Jason Scott
:"For many years now I “favourite” videos on YT by downloading them. You can't expect any video on YT to still be there tomorrow/later." YCombinator user sen, June 24, 2021, on "Older unlisted videos will be made private unless you opt out"
== Archiving tools ==
Several free FLV downloaders and video-to-URL converters exist on the web.
AT rescue projects usually use yt-dlp.
YouTube annotations (speech bubbles and notes) are available as XML
http://www.youtube.com/api/reviews/y/read2?feat=TCS&video_id=
To transform this XML to SRT, use ann2srt
=== (Automatic) tubeup.py - Youtube Video IA Archiver ===
: Note: When uploading to the Internet Archive, please avoid exposing the site to legal risk by adhering to their terms of service for blatantly copyrighted content. Unfortunately, they are subject to similar threats of DMCA takedowns as YouTube, so do use discretion.
: Note: Be very careful dumping channels over 100 videos with this script. Let an admin know what you're doing, dump 50 videos, and have a collection created. Work is being started on adding a flag to specify a collection name instead of "Community Video" which is what it defaults to. Always try to create an item. For the time being the script will have to be hand edited to specify a different collection.
tubeup.py is an automated archival script that uses yt-dlp to download a Youtube video (or any other provider supported by yt-dlp), and then uploads it with all metadata to the Internet Archive. 
This way, all metadata from the video, such as title, tags, categories, and description, are preserved in the corresponding Internet Archive item, without having to manually enter it. 
It also creates a standardized Internet Archive item name format that makes it easy to find the video using the Youtube ID, and reduces duplication: https://archive.org/details/youtube-v9sGhNoSG3o
yt-dlp also works with many other video sites.
* Github - tubeup.py
=== (Manual) Recommended way to archive YouTube videos ===
First, download the video/playlist/channel/user using yt-dlp:
yt-dlp --continue --retries 4 --write-info-json --write-description --write-thumbnail --write-annotations --all-subs --ignore-errors -f bestvideo+bestaudio URL
This can be simplified by running the script by emijrp and others, which also handles upload.
You need a recent (2014) ffmpeg or avconv for the bestvideo+bestaudio muxing to work.
Also, make sure you're using the most recent version of yt-dlp.
Then, upload it to https://archive.org/upload/ Make sure to upload not only the video itself (.mp4 and/or .mkv files), but also the metadata files created along with it (.info.json, .jpg, .annotations.xml and .description).
To capture a WARC using Warcprox, once Warcprox is running, the URL and port of the proxy can be passed to yt-dlp with the proxy parameter, for example: --proxy="localhost:8000"
Two other yt-dlp parameters for getting some more data are --write-all-thumbnails and --write-auto-sub.
=== Wayback Machine ===
YouTube URLs archived with Save Page Now will also attempt to retrieve the video data. Sometimes, the acquisition of a video does not succeed. After that, it appears that the Wayback Machine does not try saving a video again, even if manually requested.Archive of PewDiePie video "Reacting"
The watch page's video player on the Wayback Machine doesn't always work. If a video is archived, it is almost always available at https://web.archive.org/web/2oe_/http://wayback-fakeurl.archive.org/yt/VideoID. This relies on a special index which has encountered issues in the past.https://archive.org/post/1128428/the-requested-video-has-been-archived-but-is-not-currently-available-for-playback There is at least one video (m_tLmZeOOl4) where that endpoint does not report the video as archived but it is still viewable on the watch page. In this case, the https://web.archive.org/__wb/videoinfo?vtype=youtube&vid=VideoID endpoint does provide the URL to the video data. It is not clear what the difference is between the two endpoints.
=== Tools to check for regional restrictions ===
* https://watannetwork.com/tools/blocked/
* https://polsy.org.uk/stuff/ytrestrict.cgi
== Annotations removal (January 2019) ==
Annotationshttps://youtube.googleblog.com/2008/06/new-beta-feature-video-annotations.html were notes that could be added to videos after the upload, they provided plenty customization options such as color, size and internal & external links. People used them to correct mistakes in videos, created mini-games within YouTube and abused them too: "Please like and subscribe", "Watch in HD!!!"
On YouTube disabled editing and creating annotations for videos. On they were removed completely from the site and API responses (~15:00 UTC, same time when they disabled editing).
An archiving project "YouTube Annotation Archive" organized by u/omarroth that achieved to discover ~1.4 billion videos and download the annotations, if they had any. The project did not completely finish due to the deadline. The annotation archive is available at , and a compressed copy can be found at . 16GB of just video IDs that were encompassed by the project can be downloaded here.
== Liked lists (December 2019) ==
On , the playlists containing users' liked videos were made private.
== Playlist notes (October 2020) ==
On , playlist notes were removed because they were 'rarely used'.https://web.archive.org/web/20200926110942/https://support.google.com/youtube/answer/6083634 While the official documentation only talks of 'private notes', these could be public as well. Although the notes are no longer displayed, they are still included in the Polymer page source code for playlists as of and .
== Older unlisted videos (July 2021) ==
On , YouTube announced that they would make all unlisted videos uploaded before private in one month, on , unless the uploader opted-out of the changehttps://blog.youtube/news-and-events/update-youtube-unlisted-links/https://support.google.com/youtube/answer/9230970. Uploaders could also opt all of the videos on their channel out of this change by completing a formhttps://support.google.com/youtube/contact/older_unlisted_update. This change is likely because YouTube video IDs are believed to have previously been generated from an encrypted sequential integer instead of randomly, meaning that according to YouTube, the possibility of an unlisted URL being guessed was too significant. What makes the argument dubious is that the possibility is marginal to begin with, and even in the unlikely possibility of it happening, that would be one view of a random unlisted video from somewhere in the world, meaning the possibility of harm from guessed URLs did practically not exist to begin with. An HTTP 429 rate limit would have presumably been hit anyway well before any URL could be guessed through brute-forcing. Additionally, uploaders of unlisted videos consented from the beginning to the ever-so-slight possibility of their video's URL being guessed. And if this alleged security risk was known since 2017, it would mean that Google has withheld this information from users for four years.
It is expected that unlisted content from older, inactive channels will be lost because of this change.
Although the support article was updated to use past-tense language and the opt-out form was made unavailable approximately as scheduled (around the beginning of ), the videos were not made private until around the beginning of UTC. The change occurred gradually over a number of hours in alphabetical order based on the video ID, starting around and finishing around (give or take an hour or two at both ends).
== Discussions/Channel Comments (October 2021) ==
In addition, YouTube decided that their new “Community Post” feature can not co-exist with the “Discussion” feature, earlier known as “Channel Comments”. Therefore, all channels that reach a certain subscriber threshold (formerly 10000, 1500, 1000, now 500 as of ), all channel comments will be permanently erased instead of being merged or co-existing.
The owner from the YouTube channel is still able to access comments from the discussion tab for 30 days after their channel has received the community tab feature. For channel visitors, the “Discussion” tab immediately becomes inaccessible after it becomes replaced with the “Community” tab. Attempting to access the discussion tab via direct URL gets redirected to the main page of the channel.
As of 2021, the discussion tab on the mobile website now displays a message stating "The Discussion tab is no longer supported on Mobile Web. You can still access the Discussion tab on a computer or by using Desktop mode on a phone. Learn more". This change likely occurred at some point between and . It appears that the mobile app never supported the discussion tab.
On , YouTube announced that it would be removing all remaining Discussion tabs on . This will affect channels with 1,000 or fewer subscribers as well as channels which have reached more than 1,000 subscribers within the past week. On that date YouTube will also decrease the minimum number of subscribers required for a Community tab from over 1,000 to over 500.
User:Tech234a wrote a simple Python script to download discussions without an API key: https://github.com/tech234a/youtube-discussions-archive
Discussion tabs were removed from the YouTube web interface as scheduled on , with the earliest known report of removal occurring at 21:01 UTC. At some point afterwards (by ) the drop down menu for enabling/disabling Discussion tabs or setting a moderation level was removed from YouTube Studio settings. The InnerTube API endpoint used by the Archive Team project scripts continued to return Discussion tab data for approximately another week, with data becoming inaccessible using this method by around . As of , Discussion tab data is still retrievable using the public YouTube Data API. However, by , the public YouTube Data API endpoint started returning empty responses (indicating 0 comments) for all channels. This change has not been documented in the official API changelog.
=== Archival Project ===
Archive Team ran a project from through to archive the InnerTube API data responses for Discussion tab data. In addition to retrieving data from channels with visible Discussion tabs, using the InnerTube API endpoint to retrieve data also allowed retrieval of Discussion tab comments from channels that had hidden their discussion tabs or had them replaced by community tabs. Note that this project did not archive the discussion pages themselves since on the Polymer YouTube layout those pages were just wrappers that contained no comments without first making a request to the InnerTube API used by this project.
Channels were discovered from various sources, including within the project by saving channels that posted comments on other channels.
The version of the script used during the first few hours of the project had a small bug that prevented archiving more than 10 replies for a given comment. This would have only affected a small number of comments on a small number of channels, and the first 10 replies were retrieved in all cases. The affected version of the script was 20211010.02. Unfortunately, these items were not retried.
Overall, the project successfully retrieved Discussion tabs for 257.96 million YouTube channels, with data totaling 2.13TiB, which will be made available in WARC format on the Internet Archive. Because all of the requests have the same two URLs differentiated by POST data, accessing this data using the Wayback Machine may be difficult.
== Removal of public video dislikes (December 2021) ==
YouTube announced on that they would remove public display of the display count to "help better protect creators from harassment, and reduce dislike attacks". This change was rolled out gradually, and API access will be disabled on December 13th. Dislike counts continue to be visible to the person that uploaded the video as well as whitelisted API clients.
== Soft-deleted audio tracks ==
Music tracks from "topic channels" are often soft-deleted, meaning they are marked as blocked in every country. The title and metadata remain visible, but a "video unavailable" error appears in place of the video player and it can not be played.Example 1, Example 2, Example 3
== Site reconnaissance ==
Little is known about its database, but according to data from 2006, it was 45TB and doubling every 4 months. At this rate it would be 660 Petabytes as of October 2014.
According to Leo Leung's calculations based on available information, an often updated Google spreadsheet estimates that in early 2015 YouTube's content reached 500 petabytes in size.
Ethan Zuckerman's blog post estimates that there are 13.3 billion videos on YouTube based on random sampling of search results, as of December 2023. The data is available on TubeStats.
FYI, all of Google Video was about 45TB, and the Archive Team's current biggest project, URLs is roughly 10PB as of . The Internet Archive's total capacity is 150PB as of December 2023Used and Free Paired Space on https://archive.org/~tracey/stats. So let's hope YouTube stays healthy, because the Archive Team may have finally met its match.
== Vital signs ==
Will be living off Google for a long time if nothing changes.
=== Advertising policies ===
Around early 2017, numerous content creators have expressed concerns about recent changes with YouTube's advertising policies, and many have also noticed sharp drops in ad revenue as a result, with some creators like Casey Neistat and h3h3Productions expressing existential fears. While not necessarily a cause for imminent alarm, the situation should be watched closely in the event that a positive feedback loop was to begin with a creator exodus.
=== Annotations ===
On , YouTube updated its to include that all annotations (which had been disabled for new videos and replaced with "cards" early May 2017, but old annotations remained visible) will be removed from videos hosted on the platform on .
=== Discussions (Channel Comments) ===
See Discussions/Channel Comments (October 2021).
=== Removal of AutoShare ===
AutoShare was a YouTube feature, introduced in 2009, that allowed users to automatically share the following actions on YouTube to Twitter, Google Plus and formerly Facebook automatically:
* Liking a video. 
* Publishing a video.
* Adding video to playlist (AutoShare did not share name and URL of the target playlist.)
* Favourising a video (removed YouTube feature, existing favourite videos automatically got moved to “Favourites” playlist.)
The tweet or Google+ post posted by AutoShare included the title and the URL to the target video.
An AutoShared tweet's metadata source tag indicates “Google”.
 I liked a @YouTube video https://youtu.be/By_Cn5ixYLg?a YouTube Rewind 2018 but it's actually good
At some point, YouTube AutoShare tweets of the YouTube channel the video was shared from, if the owner of the YouTube channel had also linked their Twitter account to their YouTube channel and publicly listed it on the channel.
Twitter's tweet search feature allowed finding out the URL or the title of a deleted video from each other, or the original video URL and full title from knowing the approximate title.
It could also help to trace back changes of a video's title.
This information was useful to find out more about lost videos, e.g. what caused them to be removed, captures by Wayback/Archive.Today, online discussions and potential re-uploads.
On , YouTube announced https://goo.gl/ef8Vc3” that they would get rid of that feature on .
After the removal of AutoShare, people still tweeted “I liked a @YouTube video […]” manually.
=== Video Statistics ===
Without any clear warning in advance, YouTube has also entirely removed the public “video statistics” feature. The only warning sign was that their new “Polymer” website layout lacked the statistics feature, which could originally be found in the “More” menu below a video.
Only their “One” website layout that they introduced in 2013 and revised in late 2014, then barely changed for years, co-existing with “Polymer” since late 2017, included the statistics feature.When YouTube released their “One” website layout, the number of parameters displayed by the video statistics was also reduced., and .
The video statistics were also inaccessible from the “One” website since late 2018, and the API endpoints were removed as well. .
==== Parameters (legacy) ====
* Total view count + graph.
* Total comments count + graph.
* Total favourited count + graph (removed YouTube feature).
* Total rating counts (no graph)
* Like and dislike count (no graph)
* Referral sources with date of initial referral (exact dates available as of ).
** View counts from each referral source.
*** First featured video view
*** First referral from related videos (separately mentioned)
*** First view from embededd video
*** First view from embededd video (specified website)
*** First referral from YouTube search (for separate search terms)
* Most popular audiences (age and gender)
* World map that highlights countries in which the video is more popular.
** Countries with higher popularity are highlighted in darker green.
* Honour badges 
** Total honour counts
** List of honours
*** Rank: Most viewed of all time
*** This list is incomplete yet.
==== Parameters (recent) ====
* Views
* Total Watch time
** Average watch time per user.
* Subscribers gained from said video
* Share counter: How often the video was shared.
Each of these parameters could be viewed as total cumulative count or counts per day, of which the latter was the default setting.
=== “One” channel layout ===
In March 2013, YouTube enforced all channels to change to the previously optional new channel layout called “One” channel layout. 
==== Good bye, unified page. ====
“One” channel layout crippled the Wayback Machine's ability to crawl channel pages.
The Wayback Machine often just captures the home page of a YouTube channel and misses the channel subpage tabs.
Since “One” channel layout was introduced in March 2013, the information of YouTube channels is no longer unified onto a single page, but has been split up onto different, separate subpages:
* /featured (possibly formerly /home)
* /videos
* /playlists
* /community
* /store
* /channels
* /discussion
* /about 
** Does include channel views, total view count, subscriber count and channel creation date.
** Includes user-added information such as E-Mail address (ReCaptcha needed to access due to spam prevention), channel description, user-specified country, link farm.
* /search
* /feed (likely discontinued)
** (Includes ).
** Thoughts shared via the “Share your thoughts” feature (not to be confused with discussions or community) can only be written with the legacy channel layout (accessible via ?disable_polymer=1 URL parameter) but read via the new polymer channel layout too.
** This feature is potentially endangered due to the lack of support from polymer layout, and depreciation of purpose. Existing thoughts shared via this feature could be deleted.
Some channels have the custom layout feature turned off. In that case, the channel description shows on the channel's home pageChannel with “customization” turned off, found via . Original URL: , but the discussion page (usually not enabled by default in the customized channel layout mode) is enabled and accessible via the URL.
Because all this information is no longer on a single page, if the Wayback Machine captures a channel page, it often only captures the main (home) page of the channel, dismissing the information from the other channel tabs because they are on different pages instead of all information on one page.
==== Custom channel layouts ====
Due to the lack of customizability of the “One Channel Layout”, as of March 2013, all custom creative channel designs have been deleted. Also other information such as channel view counts are no longer shown, but channel view counts can still be accessed via the YouTube API..
==== Video counter ====
Prior to that layout change, when YouTube video title stood above instead of below the video, there was a menu where one could quickly see other videos uploaded by the channel. If this feature existed today, it could have helped chromebot save information about the 20 most recent uploads of a channel the video was archived from.
From March 2013 to August 2014, the video counter was still visible next the channel name, although clicking on it just refers to the /videos page of the uploaders channel instead of directly listing the recent uploads.(Couldn't find a screenshot of this former feature in action (quickly see recent videos of uploader without needing to leave watch page, by clicking on video counter). Whoever finds a screenshot of the feature in action should please add it to this reference.)
YouTube's August 2014 redesign, which has slightly changed throughout the years, co-existed with the polymer design and was fully accessible until by appending the &disable_polymer=1 or &disable_polymer=true parameter to the URL. This parameter later worked only on selected pages. In late 2020, this design required special headers to access, but as of the design became inaccessible entirely. As of , only two YouTube pages are known to still use this design: /attribution?v=[video ID] and /advanced_settings?ar=[current/recent Unix timestamp in milliseconds]. It is expected that these pages will be updated or removed soon. As of approximately or , the one known remaining feature of /advanced_settings was made obsolete and the link to that page was removed from the new YouTube Studio. On June 10 2021, the /advanced_settings page was removed and then started returning 404 not found. As of 2022, it now redirects to a channel page. The information on /attribution had been broken/missing for several years for many videos. As of some time between {{URL|1=https://web.archive.org/web/20210920210730/https://webcache.googleusercontent.com/search?q=cache%3ATKqcRDlg7U8J%3Ahttps%3A%2F%2Fwww.youtube.com%2Fattribution%3Fv%3DsYv6XRqRwDg+&cd=15&hl=en&ct=clnk&gl=us and , the video attributions page was removed and now returns a blank page with HTTP error code 410, likely removing access to the last known YouTube page with a pre-Polymer layout (with the possible exception of the embedded video player).
Since that August 2014 redesign, the number of publicly available videos is also no longer visible directly from the watch page. And also not from the channel's “about” page, but only from the search results.
However, tracks the statistics of as many YouTube channels as possible, storing historical data for three years.
=== Comment loading ===
Since approximately July 9th, 2013,Watch page on July 8, 2013; July 10, 2013 soon after YouTube's “One Channel Layout” redesign, comments “extraload” using AJAX, which means that they do not get loaded within the page itself, but only start loading after scrolling down towards the comments. This made the comment section inaccessible to the Wayback Machine. However, there was a page called youtube.com/all_comments?v=<video ID>, which actually loaded the first few comments without AJAX (included in HTML source code), but loading more comments required AJAX. But that one was discontinued and started redirecting to the main /watch?v= page since January of 2016. However, archive.today still was able to archive YouTube comments until late 2017. As of April 2019, archiving YouTube comments using http://archive.today/ is still possible by linking directly to a comment using YouTube's lc URL parameter.
* Example comment URL: https://www.youtube.com/watch?v=W3GrSMYbkBE&lc=UgxC238Gea0KGOditl54AaABAg
* Archived: http://archive.li/OXq7u
As of June 2019 YouTube's google_comment_id URL parameter does the same thing as lc (maybe it was created as a replacement for lc which might not do anything in the future, speculation of course):
* Example: https://www.youtube.com/watch?v=EaPfzgUFJyI&google_comment_id=UgyJ0eDN227JG2mDFg54AaABAg
* Archived: http://archive.vn/MRmNW
Comments on YouTube can be sorted by Top Comments or by Newest Comments. The uploader of a video can specify which way of sorting is used for the video by default, but it can be adjusted manually by the user. The default preset is Top Comments. However, no known URL parameter is able to select the sorting methods for the comments so far. Therefore, crawlers that can access the comments can only crawl them in the preselected way of sorting.
Trivia:
* The Top Comments are not necessarily the comments with the highest number of upvotes, probably because YouTube does not want always the same comments to stay on top for too long. Older comments get pushed down despite having a high rating.
* At some point, YouTube started hiding negative comment ratings and only shows how often a comment has been rated positively. Rating a comment negatively is still possible however. It's effect is pushing comments further down from the Top Comments.
=== Video Responses ===
“Video responses” was a feature where users could respond to videos with new or existing videos that were listed above the comment sections.
After YouTube removed that feature, the existing videos that were posted as response were not removed. But the links between the original video and the video used as response were removed.
=== Video reactions ===
YouTube's “Video Reactions” feature (2011) is similar to Facebook's since 2016.
The possible reactions were: “LOL, OMG, EPIC, CUTE, WTF or FAIL”. originally from .
To view reaction counts, one needed to be logged in.
But the feature got removed within just months after it's initial release, erasing all existing reactions.
=== Reasons for video deletions ===
When a video gets removed for any reason (e.g. manually removed by uploader; uploader closed channel; guideline issues; channel terminated) or not available in a specific region, YouTube usually displays the reason for why the video can not be played.
However, at some point (estimatedly 2013 or 2014), YouTube started purging unavailability reasons for manually deleted videos and videos and channel pages of closed channels, meaning that YouTube shows “This video does not exist.” or “This video is unavailable.”, as if the video never existed in first place.
Since then, reasons for videos that have been permanently erased will only be displayed for a very limited time, after which the video reads as unavailable instead of removed by user or closed channel.
Example:
* The video https://www.youtube.com/watch?v=vtdDvkI8NUA once existed, but was deleted.
* The video https://www.youtube.com/watch?v=ABCDEF12345 never existed in first place.
YouTube does not differentiate between these videos after the deletion reason gets purged.
Since 2017, a private video will also indicate as “not available” (same as a video that never existed in first place) immediately after privated, while playlists that contain the unavailable videos still indicate the distinction between private and deleted videos.
=== YouTu.be ===
YouTu.be used to be an image hoster back in 2006. In late 2015, they created a robots.txt file that disallows all crawlers (or “User-agent: * Disallow:/”).
=== yt.be ===
YouTube also operates a URL shortener at yt.be. It uses Firebase Dynamic Links.
=== Bulletins ===
YouTube used to have a feature called “Bulletins” in it's earlier years, likely introduced in 2006. 
After co-existing with “Channel Comments” that would later become “Discussions”, that feature got removed at some point, erasing all existing Bulletin posts.
=== das_captcha ===
From approximately 2010 to 2012, a whole generation of Wayback Machine captures of YouTube pages were redirected to /das_captcha by HTTP 303 request, rendering these Wayback captures next to useless.
===Inactive accounts policy ===
YouTube has an which has text dating back to at least 2009 (it was originally included as part of the Username Squatting Policy, though it was moved and renamed to its current name around 2013 or 2014). This policy states that accounts that have not logged in for 6 months, or have not uploaded any videos, or are not actively watching/commenting on videos or channels may be "reclaimed". As of 2021, . YouTube would likely notify users via email if they decided to start enforcing this policy again in the future. This policy was noticed by archivists in December 2020.
=== Attributions ===
On , YouTube announced video attribution pages would removed "after September". Video attribution pages were believed to be the final remaining page on YouTube to use the old, pre-polymer layout. As of some time between {{URL|https://web.archive.org/web/20210920210730/https://webcache.googleusercontent.com/search?q=cache%3ATKqcRDlg7U8J%3Ahttps%3A%2F%2Fwww.youtube.com%2Fattribution%3Fv%3DsYv6XRqRwDg+&cd=15&hl=en&ct=clnk&gl=us and , the video attributions page was removed and now returns a blank page with HTTP error code 410. As of this point, links to attribution pages still appear below video descriptions. At some later time this link was removed.
=== Comment Removals ===
==== COPPA comment removal ====
* In early 2020, all comments for kids videos were removed to keep in touch with USA's COPPA privacy act and European Union's Rule.
==== Pedophilia comment removal ====
* YouTube removed comments of videos that contain kids in it to prevent pedophilia.
==== Music Comment Removal ====
* In late 2020, YouTube deactivated comments under auto-generated art tracks, though they later reverted that decision in 2023.Auto-generated Art Tracks and YouTube Comments - (also see its description)Learn why comments are disabled - YouTube helpYouTube mass disables all comments on “Art Track” music videos, angering communities - 
=== Video Dislikes ===
See Removal of public video dislikes (December 2021).
== Stories ==
“Stories” was a feature of YouTube which works in a similar way to Instagram Stories, Facebook Stories and Snapchat. It can exclusively be accessed from the YouTube application for mobile devices (not YouTube's mobile website or desktop website). It allows users, momentarily exclusively with channels that have over 10000 subscribers, to publish vertical videos, usually filmed from their mobile devices, and optionally edited with e.g. text, using their basic editing features.
Creation of new Stories was discontinued in favor of Community Posts and Shorts on . All remaining Stories expired within 7 days.
=== Volatility ===
“Story” videos automatically got deleted in 7 days (= 1 week) after being posted.
=== Accessibility ===
“Stories” could be accessed from the “Stories” tab on YouTube channels when viewed in the mobile application.
== Removed or blocked channels ==
* Syrian government channels got removed (2018)
* Iranian HispanTV channel got blocked (2018) (Available from Australia FWIW)
* Nicolas Maduro channel (blocked?) (Available from Australia FWIW)
* See also: List of lost online videos
== Trivia ==
* All ytimg servers (where YouTube saved images, stylesheets and the .swf file of the flash-based YouTube video player) used to be intoxicated by robots.txt (“user-agent:* disallow:/ noindex:/”). When browsing YouTube layouts starting circa 2008 using the Wayback Machine, the website could only be viewed as black text on white background, just with different sizes (e.g. video title), due to the missing images and stylesheet information. Only information visible in the HTML source code of the page itself could be rendered. On , the robots.txt file vanished off the ytimg servers, lifting the restrictions and making YouTube more properly browse-able through the Wayback Machine.
* Yahoo and Bing Video results might contain titles, upload dates and thumbnails of unavailable YouTube videos (i.e. after privated, deleted or channel terminated). Please help saving them to Archive.Today and ArchiveBot if found, before they become purged from the results.
** Yahoo URL format: https://video.search.yahoo.com/yhs/search?hspart=ddc&p=search query
** Bing URL format: http://www.bing.com/videos/search?FORM=HDRSC3&q=search query
== Finding Archived Videos ==
The YouTube Video Finder can be used to search several different YouTube archives for individual YouTube video IDs.
== References ==
== See also ==
*Me at the zoo
== External links ==
* Official YouTube statistics (until 2017)
* TubeStats (via Dialing for Videos: A Random Sample of YouTube / How big is YouTube)
* List of the most subscribed users on YouTube
* List of most viewed YouTube videos
Category:Video hosting
Category:Google