The Dark Side of the Moon is Pink Floyd’s eighth studio album, released in 1973. It built on ideas explored in the band's earlier recordings and live shows, but lacks the extended instrumental excursions that characterised their work following the departure in 1968 of founder member, principal composer, and lyricist, Syd Barrett. The themes on The Dark Side of the Moon include conflict, greed, the passage of time, and mental illness, the latter partly inspired by Barrett's deteriorating mental state.
Developed during live performances, an early version of the suite was premiered several months before studio recording began; new material was recorded in two sessions in 1972 and 1973 at Abbey Road Studios in London. The group used some of the most advanced recording techniques of the time, including multitrack recording and tape loops. Analogue synthesizers were given prominence in several tracks, and a series of recorded interviews with the band's road crew and others provided the philosophical quotations used throughout. Engineer Alan Parsons was responsible for some of the album's most notable sonic aspects and the recruitment of non-lexical singer Clare Torry.
The album's iconic sleeve, designed by Storm Thorgerson, features a prism that represents the band's stage lighting, the record's lyrical themes, and keyboardist Richard Wright's request for a “simple and bold” design. The Dark Side of the Moon was an immediate success; it topped the Billboard Top LPs & Tapes chart for one week and remained in the charts for 741 weeks from 1973 to 1988. With an estimated 50 million copies sold, it is Pink Floyd's most commercially successful album and one of the best-selling albums worldwide.