YouTube Wiki:YouTube

YouTube is an American online video sharing and social media platform headquartered in San Bruno, California. It was launched on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim. It is owned by Google, and is the second most visited website, after Google Search. YouTube has more than 2.5 billion monthly users who collectively watch more than one billion hours of videos each day. As of May 2019, videos were being uploaded at a rate of more than 500 hours of content per minute.

In October 2006, 18 months after posting its first video and 10 months after its official launch, YouTube was bought by Google for $1.65 billion. Google's ownership of YouTube expanded the site's business model, expanding from generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by YouTube. It also offers YouTube Premium, a paid subscription option for watching content without ads. YouTube also approved creators to participate in Google's AdSense program, which seeks to generate more revenue for both parties. YouTube reported revenue of $19.8 billion in 2020. In 2021, YouTube's annual advertising revenue increased to $28.8 billion.

Since its purchase by Google, YouTube has expanded beyond the core website into mobile apps, network television, and the ability to link with other platforms. Video categories on YouTube include music videos, video clips, news, short films, feature films, documentaries, audio recordings, movie trailers, teasers, live streams, vlogs, and more. Most content is generated by individuals, including collaborations between YouTubers and corporate sponsors. Established media corporations such as Disney, Paramount, and Warner Bros. Discovery have also created and expanded their corporate YouTube channels to advertise to a larger audience.

YouTube has had an unprecedented social impact, influencing popular culture, internet trends, and creating multimillionaire celebrities. Despite all its growth and success, YouTube has been widely criticized. Criticism of YouTube includes the website being used to facilitate the spread of misinformation, copyright issues, routine violations of its users' privacy, enabling censorship, and endangering child safety and wellbeing.

History

 * Main article: YouTube Wiki:History of YouTube

Founding and initial growth (2005–2006)
YouTube was founded by Steve Chen, Chad Hurley, and Jawed Karim. The trio were early employees of PayPal, which left them enriched after the company was bought by eBay. Hurley had studied design at the Indiana University of Pennsylvania, and Chen and Karim studied computer science together at the University of Illinois at Urbana–Champaign.

According to a story that has often been repeated in the media, Hurley and Chen developed the idea for YouTube during the early months of 2005, after they had experienced difficulty sharing videos that had been shot at a dinner party at Chen's apartment in San Francisco. Karim did not attend the party and denied that it had occurred, but Chen remarked that the idea that YouTube was founded after a dinner party "was probably very strengthened by marketing ideas around creating a story that was very digestible".

Karim said the inspiration for YouTube first came from the Super Bowl XXXVIII halftime show controversy when Janet Jackson's breast was briefly exposed by Justin Timberlake during the halftime show. Karim could not easily find video clips of the incident and the 2004 Indian Ocean Tsunami online, which led to the idea of a video-sharing site. Hurley and Chen said that the original idea for YouTube was a video version of an online dating service, and had been influenced by the website Hot or Not. They created posts on Craigslist asking attractive women to upload videos of themselves to YouTube in exchange for a $100 reward. Difficulty in finding enough dating videos led to a change of plans, with the site's founders deciding to accept uploads of any video.

YouTube began as a venture capital–funded technology startup. Between November 2005 and April 2006, the company raised money from various investors, with Sequoia Capital, $11.5 million, and Artis Capital Management, $8 million, being the largest two. YouTube's early headquarters were situated above a pizzeria and Japanese restaurant in San Mateo, California. In February 2005, the company activated www.youtube.com. The first video was uploaded April 23, 2005. Titled Me at the zoo, it shows co-founder Jawed Karim at the San Diego Zoo and can still be viewed on the site. In May, the company launched a public beta and by November, a Nike ad featuring Ronaldinho became the first video to reach one million total views. The site launched officially on December 15, 2005, by which time the site was receiving 8 million views a day. Clips at the time were limited to 100 megabytes, as little as 30 seconds of footage.

Contrary to popular belief, YouTube was not the first video-sharing site on the Internet; Vimeo was launched in November 2004, though that site remained a side project of its developers from CollegeHumor at the time and did not grow much, either. The week of YouTube's launch, NBC-Universal's Saturday Night Live ran a skit "Lazy Sunday" by The Lonely Island. Besides helping to bolster ratings and long-term viewership for Saturday Night Live, "Lazy Sunday"'s status as an early viral video helped establish YouTube as an important website. Unofficial uploads of the skit to YouTube drew in more than five million collective views by February 2006 before they were removed when NBCUniversal requested it two months later based on copyright concerns. Despite eventually being taken down, these duplicate uploads of the skit helped popularize YouTube's reach and led to the upload of more third-party content. The site grew rapidly; in July 2006, the company announced that more than 65,000 new videos were being uploaded every day and that the site was receiving 100 million video views per day.

The choice of the name www.youtube.com led to problems for a similarly named website, www.utube.com. That site's owner, Universal Tube & Rollform Equipment, filed a lawsuit against YouTube in November 2006 after being regularly overloaded by people looking for YouTube. Universal Tube subsequently changed its website to www.utubeonline.com.

Broadcast Yourself era (2006–2013)
On October 9, 2006, Google announced that it had acquired YouTube for $1.65 billion in Google stock. The deal was finalized on November 13, 2006. Google's acquisition launched new newfound interest in video-sharing sites; IAC, which now owned Vimeo, focused on supporting the content creators to distinguish itself from YouTube. It is at this time YouTube issued the slogan "Broadcast Yourself".

The company experienced rapid growth. The Daily Telegraph wrote that in 2007, YouTube consumed as much bandwidth as the entire Internet in 2000. By 2010, the company had reached a market share of around 43% and more than 14 billion views of videos, according to comScore. That year, the company simplified its interface to increase the time users would spend on the site. In 2011, more than three billion videos were being watched each day with 48 hours of new videos uploaded every minute. However, most of these views came from a relatively small number of videos; according to a software engineer at that time, 30% of videos accounted for 99% of views on the site. That year, the company again changed its interface and at the same time, introduced a new logo with a darker shade of red. A subsequent interface change, designed to unify the experience across desktop, TV, and mobile, was rolled out in 2013. By that point, more than 100 hours were being uploaded every minute, increasing to 300 hours by November 2014.

During this time, the company also went through some organizational changes. In October 2006, YouTube moved to a new office in San Bruno, California. Hurley announced that he would be stepping down as a chief executive officer of YouTube to take an advisory role and that Salar Kamangar would take over as head of the company in October 2010.

In December 2009, YouTube partnered with Vevo. In April 2010, Lady Gaga's "Bad Romance" became the most viewed video, becoming the first video to reach 200 million views on May 9, 2010.

YouTube's new CEO and going mainstream (2014–2018)
Susan Wojcicki was appointed CEO of YouTube in February 2014. In January 2016, YouTube expanded its headquarters in San Bruno by purchasing an office park for $215 million. The complex has 51,468 square metres (554,000 square feet) of space and can house up to 2,800 employees. YouTube officially launched the "polymer" redesign of its user interfaces based on Material Design language as its default, as well a redesigned logo that is built around the service's play button emblem in August 2017.

Through this period, YouTube tried several new ways to generate revenue beyond advertisements. In 2013, YouTube launched a pilot program for content providers to offer premium, subscription-based channels. This effort was discontinued in January 2018 and relaunched in June, with US$4.99 channel subscriptions. These channel subscriptions complemented the existing Super Chat ability, launched in 2017, which allows viewers to donate between $1 and $500 to have their comment highlighted. In 2014, YouTube announced a subscription service known as "Music Key," which bundled ad-free streaming of music content on YouTube with the existing Google Play Music service. The service continued to evolve in 2015 when YouTube announced YouTube Red, a new premium service that would offer ad-free access to all content on the platform (succeeding the Music Key service released the previous year), premium original series, and films produced by YouTube personalities, as well as background playback of content on mobile devices. YouTube also released YouTube Music, a third app oriented towards streaming and discovering the music content hosted on the YouTube platform.

The company also attempted to create products appealing to specific viewers. YouTube released a mobile app known as YouTube Kids in 2015, designed to provide an experience optimized for children. It features a simplified user interface, curated selections of channels featuring age-appropriate content, and parental control features. Also in 2015, YouTube launched YouTube Gaming—a video gaming-oriented vertical and app for videos and live streaming, intended to compete with the Amazon.com-owned Twitch.

The company was attacked on April 3, 2018, when a shooting occurred at YouTube's headquarters in San Bruno, California, which wounded four and resulted in one death (the shooter).

Consolidation and controversy (2019–present)
By February 2017, one billion hours of YouTube were watched every day, and 400 hours of video were uploaded every minute. Two years later, the uploads had risen to more than 500 hours per minute. During the COVID-19 pandemic, when most of the world was under stay-at-home orders, usage of services like YouTube significantly increased. One data firm estimated that YouTube was accounting for 15% of all internet traffic, twice its pre-pandemic level. In response to EU officials requesting that such services reduce bandwidth as to make sure medical entities had sufficient bandwidth to share information, YouTube and Netflix stated they would reduce streaming quality for at least thirty days as to cut bandwidth use of their services by 25% to comply with the EU's request. YouTube later announced that they would continue with this move worldwide: "We continue to work closely with governments and network operators around the globe to do our part to minimize stress on the system during this unprecedented situation."

Following a 2018 complaint alleging violations of the Children's Online Privacy Protection Act (COPPA), the company was fined $170 million by the FTC for collecting personal information from minors under the age of 13. YouTube was also ordered to create systems to increase children's privacy. Following criticisms of its implementation of those systems, YouTube started treating all videos designated as "made for kids" as liable under COPPA on January 6, 2020. Joining the YouTube Kids app, the company created a supervised mode, designed more for tweens, in 2021. Additionally, to compete with TikTok, YouTube released YouTube Shorts, a short-form video platform.

During this period, YouTube entered disputes with other tech companies. For over a year, in 2018 and 2019, no YouTube app was available for Amazon Fire products. In 2020, Roku removed the YouTube TV app from its streaming store after the two companies were unable to reach an agreement.

In 2022, YouTube launched an experiment where the company would show users who watched longer videos on TVs a long chain of short unskippable adverts, intending to consolidate all ads into the beginning of a video. Following immense public outrage over the unprecedented amount of unskippable ads, YouTube "ended" the experiment on September 19 of that year.

YouTube public dislike count removal (2021–present)
After testing earlier in 2021, YouTube removed public display of dislike counts on videos in November 2021, claiming the reason for the removal was, based on its internal research, that users often used the dislike feature as a form of cyberbullying and brigading. While some users praised the move as a way to discourage trolls, others felt that hiding dislikes would make it harder for viewers to recognize clickbait or unhelpful videos and that other features already existed for creators to limit bullying. Some theorized the removal of dislikes was influenced by YouTube Rewind 2018, which was heavily panned and became the most-disliked video on the platform. YouTube co-founder Jawed Karim referred to the update as "a stupid idea", and that the real reason behind the change was "not a good one, and not one that will be publicly disclosed." He felt that users' ability on a social platform to identify harmful content was essential, saying, "The process works, and there's a name for it: the wisdom of the crowds. The process breaks when the platform interferes with it. Then, the platform invariably declines." Shortly after the announcement, software developer Dmitry Selivanov created Return YouTube Dislike, an open-source, third-party browser extension for Chrome and Firefox that allows users to see a video's number of dislikes. In a letter published on January 25, 2022, YouTube CEO Susan Wojcicki acknowledged that removing public dislike counts was a controversial decision, but reiterated that she stands by this decision, claiming that "it reduced dislike attacks."

Video technology
YouTube primarily uses the VP9 and H.264/MPEG-4 AVC video codecs, and the Dynamic Adaptive Streaming over HTTP protocol. MPEG-4 Part 2 streams contained within 3GP containers are also provided for low bandwidth connections. By January 2019, YouTube had begun rolling out videos in AV1 format. In 2021 it was reported that the company was considering requiring AV1 in streaming hardware in order to decrease bandwidth and increase quality. Video is usually streamed alongside the Opus and AAC audio codecs.

At launch in 2005, viewing YouTube videos on a personal computer required the Adobe Flash Player plug-in to be installed in the browser. In January 2010, YouTube launched an experimental version of the site that used the built-in multimedia capabilities of web browsers supporting the HTML5 standard. This allowed videos to be viewed without requiring Adobe Flash Player or any other plug-in to be installed. On January 27, 2015, YouTube announced that HTML5 would be the default playback method on supported browsers. With the switch to HTML5 video streams using Dynamic Adaptive Streaming over HTTP (MPEG-DASH), an HTTP-based adaptive bit-rate streaming solution optimizes the bitrate and quality for the available network.

The platform can serve videos at optionally lower resolution levels starting at 144p for smoothening playback in areas and countries with limited Internet speeds, improving compatibility, as well as for the preservation of limited cellular data plans. The resolution setting can be adjusted automatically based on detected connection speed, as well as be set manually.

From 2008 to 2017, users could add "annotations" to their videos—such as pop-up text messages and hyperlinks, which allowed for interactive videos. By 2019 all annotations had been removed from videos, breaking some videos which depended on the feature. YouTube introduced standardized widgets intended to replace annotations in a cross-platform manner, including "end screens" (a customizable array of thumbnails for specified videos displayed near the end of the video).

In 2018, YouTube became an ISNI registry, and announced its intention to begin creating ISNI identifiers to uniquely identify the musicians whose videos it features. In 2020 it launched video chapters as a way to structure videos and improve navigation.

Uploading
All YouTube users can upload videos up to 15 minutes each in duration. Users can verify their account, normally through a mobile phone, to gain the ability to upload videos up to 12 hours in length, as well as produce live streams. When YouTube was launched in 2005, it was possible to upload longer videos, but a 10-minute limit was introduced in March 2006 after YouTube found that the majority of videos exceeding this length were unauthorized uploads of television shows and films. The 10-minute limit was increased to 15 minutes in July 2010. Videos can be at most 256 GB in size or 12 hours, whichever is less. As of 2021, automatic closed captions using speech recognition technology when a video is uploaded is available in 13 languages, and can be machine-translated during playback.

YouTube also offers manual closed captioning as part of its creator studio. YouTube formerly offered a 'Community Captions' feature, where viewers could write and submit captions for public display upon approval by the video uploader, but this was deprecated in September 2020.

YouTube accepts the most common container formats, including MP4, Matroska, FLV, AVI, WebM, 3GP, MPEG-PS, and the QuickTime File Format. Some intermediate video formats (i.e., primarily used for professional video editing, not for final delivery or storage) are also accepted, such as ProRes. YouTube provides recommended encoding settings.

Each video is identified by an eleven-character case-sensitive alphanumerical Base64 string in the Uniform Resource Locator (URL) which can contain letters, digits, an underscore (_), and a dash (-).

In 2018, YouTube added a feature called Premiere which displays a notification to the user mentioning when the video will be available for the first time, like for a live stream but with a prerecorded video. When the scheduled time arrives, the video is aired as a live broadcast with a two-minute countdown. Optionally, a premiere can be initiated immediately.

Quality and formats
YouTube originally offered videos at only one quality level, displayed at a resolution of 320×240 pixels using the Sorenson Spark codec (a variant of H.263), with mono MP3 audio. In June 2007, YouTube added an option to watch videos in 3GP format on mobile phones. In March 2008, a high-quality mode was added, which increased the resolution to 480×360 pixels. In December 2008, 720p HD support was added. At the time of the 720p launch, the YouTube player was changed from a 4:3 aspect ratio to a widescreen 16:9. With this new feature, YouTube began a switchover to H.264/MPEG-4 AVC as its default video compression format. In November 2009, 1080p HD support was added. In July 2010, YouTube announced that it had launched a range of videos in 4K format, which allows a resolution of up to 4096×3072 pixels. In July 2010, support for 4K resolution was added, with the videos playing at 3840 × 2160 pixels. In June 2015, support for 8K resolution was added, with the videos playing at 7680×4320 pixels. In November 2016, support for HDR video was added which can be encoded with hybrid log–gamma (HLG) or perceptual quantizer (PQ). HDR video can be encoded with the Rec. 2020 color space.

In June 2014, YouTube began to deploy support for high frame rate videos up to 60 frames per second (as opposed to 30 before), becoming available for user uploads in October. YouTube stated that this would enhance "motion-intensive" videos, such as video game footage.

YouTube videos are available in a range of quality levels. Viewers only indirectly influence the video quality. In the mobile apps, users choose between "Auto", which adjusts resolution based on the internet connection, "High Picture Quality" which will prioritize playing high-quality video, "Data saver" which will sacrifice video quality in favor of low data usage and "Advanced" which lets the user choose a stream resolution. On desktop, users choose between "Auto" and a specific resolution. It is not possible for the viewer to directly choose a higher bitrate (quality) for any selected resolution.

Since 2009, viewers have had the ability to watch 3D videos. In 2015, YouTube began natively supporting 360-degree video. Since April 2016, it allowed live streaming 360° video, and both normal and 360° video at up to 1440p, and since November 2016 both at up to 4K (2160p) resolution. Citing the limited number of users who watched more than 90-degrees, it began supporting an alternative stereoscopic video format known as VR180 which it said was easier to produce, which allows users to watch any video using virtual reality headsets.

In response to increased viewership during the COVID-19 pandemic, YouTube temporarily downgraded the quality of its videos. YouTube developed its own chip, called Argos, to help with encoding higher resolution videos in 2021.

In certain cases, YouTube allows the uploader to upgrade the quality of videos uploaded a long time ago in poor quality. One such partnership with Universal Music Group included remasters of 1,000 music videos.

Platforms
Most modern smartphones are capable of accessing YouTube videos, either within an application or through an optimized website. YouTube Mobile was launched in June 2007, using RTSP streaming for the video. Not all of YouTube's videos are available on the mobile version of the site.

Since June 2007, YouTube's videos have been available for viewing on a range of Apple products. This required YouTube's content to be transcoded into Apple's preferred video standard, H.264, a process that took several months. YouTube videos can be viewed on devices including Apple TV, iPod Touch and the iPhone.

The mobile version of the site was relaunched based on HTML5 in July 2010, avoiding the need to use Adobe Flash Player and optimized for use with touch screen controls. The mobile version is also available as an app for the Android platform.

In September 2012, YouTube launched its first app for the iPhone, following the decision to drop YouTube as one of the preloaded apps in the iPhone 5 and iOS 6 operating system. According to GlobalWebIndex, YouTube was used by 35% of smartphone users between April and June 2013, making it the third-most used app.

A TiVo service update in July 2008 allowed the system to search and play YouTube videos.

In January 2009, YouTube launched "YouTube for TV", a version of the website tailored for set-top boxes and other TV-based media devices with web browsers, initially allowing its videos to be viewed on the PlayStation 3 and Wii video game consoles.

During the month of June that same year, YouTube XL was introduced, which has a simplified interface designed for viewing on a standard television screen. YouTube is also available as an app on Xbox Live.

On November 15, 2012, Google launched an official app for the Wii, allowing users to watch YouTube videos from the Wii channel, but was discontinued in June 2017. An app was available for Wii U and Nintendo 3DS, but the latter was discontinued in August 2019. Videos can also be viewed on the Wii U Internet Browser using HTML5. Google made YouTube available on the Roku player on December 17, 2013, and, in October 2014, the Sony PlayStation 4.

YouTube launched as a downloadable app for the Nintendo Switch in November 2018.