The songwriting partnership credited on many Beatles songs by Paul McCartney and John Lennon was Lennon–McCartney. The shared credit generally appears with Lennon’s name first, although some early releases used the reverse order, McCartney–Lennon.
Lennon and McCartney began writing together after meeting on 6 July 1957, when McCartney watched Lennon perform with the Quarrymen at a church fête in Woolton, Liverpool. They soon joined forces in the group and wrote songs together at locations including McCartney’s family home and Lennon’s aunt’s house.
Their agreement was unusually broad: songs written individually by either man during the partnership were generally credited to both. This explains why the label appears on songs whose musical or lyrical origins were largely associated with one writer. The pair published approximately 180 jointly credited songs between 1962 and 1970.
The credit does not mean every song was literally written side by side. Early compositions often involved extensive collaboration, while later songs were frequently begun or completed by one partner with limited assistance from the other. The arrangement also excluded George Harrison and Ringo Starr from the partnership credit, despite their important Beatles contributions.