A while ago, YouTube launched a simple demo of an HTML5-based video player. Recently, we published a blog post on our pre-spring cleaning effort and your number one request was that YouTube do more with HTML5. Today, we're introducing an experimental version of an HTML5-supported player.
HTML5 is a new web standard that is gaining popularity rapidly and adds many new features to your web experience. Most notably for YouTube users, HTML5 includes support for video and audio playback. This means that users with an HTML5 compatible browser, and support for the proper audio and video codecs can watch a video without needing to download a browser plugin.