OggVorbis is the patent-free audio format written and sponsored by Xiph.org [http://www.Xiph.org].
It uses the OggContainer multimedia file format (which is also used for other Xiph.org projects such as OggTarkin, OggTheora, and OggSpeex.
OggVorbis is generally described as having sound quality on par with or slightly better than an MP3 of the same bitrate. It has never gained widespread acceptance, however, because it lacks support in portable players.
OggVorbis is of interest to programmers who need to work with audio encoding but wish to avoid the patent fees associated with the MP3 format.