YouTube now uses HTML5 by default in Chrome, Internet Explorer 11, Safari 8 and beta versions of Firefox. YouTube announced HTML5 support four years ago; however, HTML5 limitations did not allow YouTube to move away from Flash as its default. Since its initial announcement, YouTube has worked with browser vendors and others to close technology gaps and shortcomings. The progress made in that time has enabled YouTube to default to HTML5 in most scenarios.
Key technology improvements in the HTML5 environment led to YouTube's decision. First, adaptive bitrate (ABR) streaming represents a critical component to streaming video without excessive buffering. Four years ago, HTML5 lacked ABR support, but that has changed. Additionally, HTML5 allows the use of open VP9 codec, which produces higher video resolution with lower bandwidth usage. Next, Encrypted Media Extensions separate the work of content protection from delivery, which allows YouTube to use a single video player across platforms. Platforms like Flash and Silverlight link content protection with the delivery platform, which limits capacity. WebRTC support grants users cutting-edge sharing technology without plug-ins. Finally, a new full-screen API provides an immersive viewing experience.
YouTube is one of many video companies making the move to HTML5. Netflix, Vimeo, Microsoft, Apple and others have contributed to the development of HTML5 and have helped the industry move away from legacy Flash technology. With the added improvements to HTML5 over the last few years, both traditional technology giants and new technology have benefited. For instance, HTML5 has made the way for advancements like Chromebooks and smart TVs. Many have resisted the move to HTML5 due to certain restrictions. However, with the advancements made in the past few years, industry leaders now feel comfortable with HTML5. Expect this trend to continue, and consider whether your platform or application should make a similar transition.