William Everett Preston (September 2, 1946 – June 6, 2006) was an American keyboardist, singer, and songwriter whose work encompassed R&B, rock, soul, funk, and gospel. Preston was a top session keyboardist in the 1960s, backing Little Richard, Sam Cooke, Ray Charles, the Everly Brothers, Reverend James Cleveland, the Beatles, and the Rolling Stones. He gained attention as a solo artist with hit singles "That's the Way God Planned It", the Grammy-winning "Outa-Space", "Will It Go Round in Circles", "Space Race", "Nothing from Nothing", and "With You I'm Born Again". Additionally, Preston co-wrote "You Are So Beautiful", which became a hit for Joe Cocker.
Preston is one of very few musicians to be given a credit on a Beatles recording, which was done at the band's request; the group's 1969 single "Get Back" was credited as "The Beatles with Billy Preston". He is one of several people referred to as a fifth Beatle. Preston continued to record and perform with George Harrison after the Beatles' breakup, along with other artists such as Eric Clapton and the Rolling Stones on many of the group's albums and tours during the 1970s.