MP3 is an audio-specific format that was designed by theMoving Picture Experts Group as part of itsMPEG-1 standard and later extended inMPEG-2 standard. The first MPEG subgroup -Audio group was formed by several teams of engineers atFraunhofer IIS,University of Hannover,AT&T-Bell Labs,Thomson-Brandt,CCETT, and others. MPEG-1 Audio (MPEG-1 Part 3), which included MPEG-1 Audio Layer I, II and III was approved as a committee draft ofISO/IEC standard in 1991, finalised in 1992 and published in 1993 (ISO/IEC 11172-3:1993). Backwards compatible MPEG-2 Audio (MPEG-2 Part 3) with additional bit rates and sample rates was published in 1995 (ISO/IEC 13818-3:1995).
