Users of Chrome and Internet Explorer 11, and current beta users of Firefox, have one less reason to use Flash as YouTube begins to serve up its HTML5 player by default.
For some time, YouTube has offered its HTML5 beta, but not all videos were able to be served with it. In particular, support in HTML5 for Encrypted Media Extensions (EME) has allowed YouTube to provide a ubiquitous digital rights management solution.
The last holdout on EME, Mozilla, folded on the issue in May last year.
"Encrypted Media Extensions separate the work of content protection from delivery, enabling content providers like YouTube to use a single HTML5 video player across a wide range of platforms," said YouTube Engineering manager Richard Leider in a blog post.
"Combined with common encryption, we can support multiple content protection technologies on different platforms with a single set of assets, making YouTube play faster and smoother."
The move to HTML5 video element has also allowed YouTube to begin deprecating its old object-based embed code, and move to iframes.
"We encourage all embedders to use the <iframe> API, which can intelligently use whichever technology the client supports," Leider said.
The HTML5 player replaces YouTube's video player based on Adobe's Flash plugin, which has once again fallen foul of a cascade of zero-day attacks.
YouTube is also touting the use of its VP9 codec, which YouTube said it has served up "hundreds of billions" of times already, and adaptive bitrate streaming as mechanisms to reduce the bandwidth needed to stream high-quality video with less buffering.
"These advancements have benefited not just YouTube's community, but the entire industry. Other content providers like Netflix and Vimeo, as well as companies like Microsoft and Apple, have embraced HTML5 and been key contributors to its success," said Leider.
"By providing an open standard platform, HTML5 has also enabled new classes of devices like Chromebooks and Chromecast."