The song is written by Roger Waters. It begins with an iterative bass line before the vocals start. The first, gentler vocals are performed by Richard Wright with Waters whispering, the following, harder refrain by David Gilmour. The last two minutes feature for the first time a guitar solo from Gilmour on a Pink Floyd album, featuring his distinctive style of playing single notes treated with effects such as distortion and echo.
A rare US-only single release (Tower 440) contains edited mono versions of this song and "Remember a Day". The single did not chart. Pink Floyd performed the song live from 1968-69, often as an encore.