"Get Back" is a song recorded by the Beatles and written by Paul McCartney (though credited to Lennon-McCartney), originally released as a single on 11 April 1969 and credited to "The Beatles with Billy Preston." A different mix of the song later became the closing track of Let It Be (1970), which was the Beatles' last album released just after the group split. The single version was later issued on the compilation albums 1967–1970, 20 Greatest Hits, Past Masters, and 1.

The single reached number one in the United Kingdom, the United States, Ireland, Canada, New Zealand, the Netherlands, Australia, France, West Germany, Mexico, Norway, Switzerland, Austria, and Belgium. It was the Beatles' only single that credited another artist at their request. "Get Back" was the Beatles' first single release in true stereo in the US. In the UK, the Beatles' singles remained monaural until the following release, "The Ballad of John and Yoko".

"Get Back" is unusual in the Beatles' canon in that almost every moment of the song's evolution has been extensively documented, from its beginning as an offhand riff to its final mixing in several versions. Much of this documentation is in the form of illegal (but widely available) bootleg recordings, and is recounted in the book Get Back: The Unauthorized Chronicle of the Beatles' Let It Be Disaster by Doug Sulpy and Ray Schweighardt.

The song's melody grew out of some unstructured jamming on 7 January 1969 during rehearsal sessions on the sound stage at Twickenham Studios. Over the next few minutes, McCartney introduced some of the lyrics, reworking "Get back to the place you should be" from fellow Beatle George Harrison's "Sour Milk Sea" into "Get back to where you once belonged". McCartney had played bass on Jackie Lomax's recording of "Sour Milk Sea" a few months earlier. On 9 January McCartney brought a more developed version of "Get Back" to the group, with the "Sweet Loretta" verse close to its finished version. For the press release to promote the "Get Back" single, McCartney wrote, "We were sitting in the studio and we made it up out of thin air ... we started to write words there and then ... when we finished it, we recorded it at Apple Studios and made it into a song to roller-coast by."

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