Digital media needs metadata to be supremely useful. For example, wouldn’t it be nice if your CD player showed you artist, album, and track information while it was playing a song? MP3 tracks have ID3 tags to supply this information, but naturally, Microsoft has created an extensive set of APIs for embedding metadata in all types of media. This article will bring you up to speed on metadata support for media encoding, playback, and more.

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnwmt/html/WM_Metadata_Us
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