Ogg is a data container created specifically for multimedia data by the Xiph.Org Foundation. As a container, Ogg supports several different formats for storing multimedia data like music, video, and speech. Ogg is impressive because all of its formats are open source and completely patent and royalty free. Ogg currently supports the following formats: Flac, Speex, Theora, and Vorbis. It also includes libraries for those formats and also the Icecast and Paranoia protocols.

The name Ogg isn't an acronym but a word used in a game called Netrek. Ogg is a tactical maneuver meaning to do something forcefully without consideration of the drain on future resources.