Video format that wouldn't require a browser plugin

Question

What is the recommended (cross-browser) video format to use on websites so that users' browsers (or most of them) wouldn't require to download a plugin to view it?

Answer 1

There is no single video that will play in every browser. If you want it to work across the most browsers, you're going to have to encode your video more than once. Dive into HTML5 video has the gory details.

You nest your video references so that browsers try these in order, falling back if it's not supported:

1. Ogg Theora
2. MP4 H.264
3. A Flash container displaying #2

Number 1 gets you Firefox 3.5 and Chrome. Number 2 gets you Safari and the mobile phone WebKit browsers. Number 3 gets you IE, Firefox ≤3, and Opera.

Answer 2

There is no such format available yet. The best way to go is:

1. Flash (most of the users have flash plugin installed already, 99% according to http://www.adobe.com/products/player_census/flashplayer/)
2. OGG (This will be available in HTML5 as standard)