The Compact Cassette, also known as an audio cassette or cassette tape, is an analog magnetic tape format used for audio recording and playback. Developed by Lou Ottens and his team at Philips in the Netherlands, it was introduced in August 1963. Compact Cassettes were available both as prerecorded music cassettes (Musicassettes) and as blank tapes for home recording.

The Beatles' U.K. cassette catalog began in 1967 with Sgt. Pepper's Lonely Hearts Club Band, followed by Abbey Road in 1969 and Let It Be in August 1970. Most of the group's earlier albums were first issued on cassette in September and October 1970, shortly after EMI opened its new tape duplication facilities at Hayes, Middlesex, in July 1970.