HTML5 video
In 2010, in the wake of Apple iPad launch and after Steve Jobs announced that Apple mobile devices would not support Flash, a number of high-profile sites began to serve H.264 HTML5 video instead of Adobe Flash for user-agents identifying as iPad. HTML5 video was not as widespread as Flash videos, though there were rollouts of experimental HTML5-based video players from DailyMotion (using Ogg Theora and Vorbis format), YouTube (using the H.264 and WebM formats), and Vimeo (using the H.264 format).
Comparison of HTML5 and Flash
Both Flash and HTML text can be read by screen readers. However, special care must be taken to ensure Flash movies are read correctly. For example, if a Flash movie is set to repeat indefinitely, this can cause a screen reader to repeat the content endlessly. Selecting the "Make object accessible" check box in Adobe Flash Professional will create a text-only version of the object for screen readers. It will also hide any motion from the screen reader. Since Flash content is usually placed on a single webpage, it appears as a single entry in search engine result pages, unless techniques like deep linking are used with libraries like SWFAddress to provide multiple links within Flash websites and web applications. User interface widgets in Flash objects don't always behave like their host native counterparts. Keyboard, mouse and other accessibility shortcuts may not work unless the webpage developer explicitly adds support for it.