H.264 is a type of MPEG-4 video compression, offering higher quality video in a smaller file size than MPEG-2 (standard DVD video format) or MPEG-4 ASP (DivX format). It is the default file format of Apple’s QuickTime, and there is a petition to make it a standard video format for the next generation of the HTML Web programming language (HTML5). Windows 7 includes native support for H.264-encoded videos, but early versions will need a proper codec to play the video back correctly. Tips Writer Bio

How to Install the QuickTime H 264 Codec - 90