A: WebM is an open media file format, which, as the name suggests, is designed for media playback of the web. The WebM format uses the VP8 video codec for compression and Vorbis for the audio.

See the WebM Project page for details. The WebM add-on for Internet Explorer 9 can be found at this website.

To see more FAQs, please go to John Savill's FAQs page on Windows IT Pro.