And don't forget to add the mime types in your webserver (Apache, Nginx, etc...):
-
video/mp4
for.mp4
: for Internet Explorer 9+ and Safari 5+ -
video/ogg
for.ogv
: for Firefox 3.5+, Opera 10.5+ and Google Chrome +6 (and Internet Explorer 9+ if the codec is installed) -
video/webm
for.webm
: for Firefox 4+, Opera 10.6+ and Google Chrome 6+ (and Internet Explorer 9+ if the codec is installed) -
application/x-shockwave-flash
for.swf
: for all browsers with Flash installed
You can use Miro Video Converter to generate all versions of the video and Flashdevelop to make a Flash movie.
If you plan to support iOS users (iPhone / iPad), your HTML5 video must have controls enabled because Apple forbids autoplaying videos, even using a script; there used to be hacks until iOS 4.2, but they are no longer usable.