Pink Floyd were an English rock (Rock music) band who earned recognition for their psychedelic (psychedelic rock) music in the late 1960s, and as they evolved in the 1970s, for their progressive rock music. Pink Floyds work is marked by the use of philosophical lyrics, sonic experimentation (Acoustics), innovative album cover art (album art), and elaborate live shows (Pink Floyd live performances). One of rock musics most critically acclaimed and commercially successful acts, the group have sold over 200 million albums worldwide, including 74.5 million certified units in the United States, making them one of the best-selling music artists (list of best-selling music artists) of all time.

Pink Floyd were formed in 1965, and originally consisted of university students Roger Waters, Nick Mason, Richard Wright (Richard Wright (musician)), and Syd Barrett. The group were a popular fixture on Londons underground music scene, and under Barretts leadership released two charting singles, "Arnold Layne" and "See Emily Play", and a commercially and critically successful debut album, The Piper at the Gates of Dawn. In 1968, guitarist and singer David Gilmour joined the line-up, and Barrett was removed due to his increasingly erratic behaviour. Following Barretts departure, bass player and singer Roger Waters became the lyricist and dominant figure in the band, which went on to achieve worldwide critical and commercial success with the concept albums The Dark Side of the Moon, Wish You Were Here (Wish You Were Here (Pink Floyd album)), Animals (Animals (album)), and rock opera The Wall.

Wright left the band in 1979, and Waters in 1985, but Gilmour and Mason (joined by Wright) continued recording and touring under the name Pink Floyd. Waters used legal means to try to keep them from using the name, declaring Pink Floyd a spent force, but the parties reached an out-of-court settlement allowing Gilmour, Mason and Wright to continue as Pink Floyd. The band again enjoyed worldwide success with A Momentary Lapse of Reason (1987) and The Division Bell (1994), and Waters continued as a solo musician, releasing three studio albums. Although for some years relations between Waters and the remaining three members were sour, the band reformed in 2005 for what would be a final one-off performance at Live 8.