The Compact Cassette or Musicassette (MC), also commonly called the tape cassette,cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback It was introduced in September 1963. Compact Cassettes come in two forms, either already containing content as a prerecorded cassette (Musicassette), or as a fully recordable "blank" cassette. Both forms have two sides and are reversible by the user.