HTML5 video
Support for HTML5 video has been steadily increasing. In June 2013, Netflix added support for HTML5 video. In January 2015, YouTube switched to using HTML5 video instead of Flash by default. In December 2015, Facebook switched from Flash to HTML5 for all video content.
HTML5
The HTML 5 syntax is no longer based on SGML despite the similarity of its markup. It has, however, been designed to be backward-compatible with common parsing of older versions of HTML. It comes with a new introductory line that looks like an SGML document type declaration, codice_1, which triggers the standards-compliant rendering mode.
Since 5 January 2009, HTML 5 also includes "Web Forms 2.0", a previously separate WHATWG specification.