2005: YouTube is born
Me at the Zoo is the first video uploaded to YouTube
2006: Google buys YouTube
One year after YouTube launches, videos play in the FLV container with the H.263 codec at a maximum resolution of 240p. We scale videos up to 640x360, but you can still click a button to play at original size.
2007: YouTube goes mobile
YouTube is one of the original applications on the iPhone. Because it doesn't support Flash, we re-encode every single YouTube video into H.264 with the MP4 container. YouTube videos get a resolution notch to 360p.
2008: YouTube kicks it up to HD
With upload sizes and download speeds growing, videos jump in size up to 720p HD. Lower resolution files get higher quality by squeezing Main Profile H.264 into FLVs.
2009: YouTube enters the third dimension
YouTube supports 3D videos, 1080p and live streaming.
2010: YouTube's on TV
The biggest screen in your house now gets YouTube courtesy of Flash Lite and ActionScript 2. 2010 also sees the first playbacks with HTML5 <video> thanks to VP8, an open source video codec. We bump up the maximum resolution to 4K, known as "Original" at the time.
2011: YouTube slices bread (and videos) to battle buffering
We launch Sliced Bread, codename for a project that enables adaptive bitrate in the Flash player by requesting videos a little piece at a time. Users see higher quality videos more often and buffering less often.
2012: YouTube live streaming hits prime time
We scale up our live streaming infrastructure to support the 2012 Summer Olympics, with over 1,200 events. In October, over 8 million people watch live as Felix Baumgartner jumps from the stratosphere.
2013: YouTube's first taste of VP9
We start our first experiments with VP9 in Chrome, which brings higher quality video at less bandwidth. Adaptive bitrate streaming in the HTML5 and Flash players moves to the DASH standard using both FMP4 and MKV video containers.
2014: Silky smooth 60fps comes to YouTube
High frame rate isn't just for games anymore: YouTube now supports videos that play in up to 60fps. Gangnam Style becomes the first YouTube video to break the MAX_INT barrier with more than 232 / 2 - 1 views.
2015: YouTube adds spherical video (look behind you!)
You can now upload videos that wrap 360 degrees around the viewer. Even 4K videos can play up to 60fps. HTML5 becomes the default YouTube web player.