Lennon–McCartney was the songwriting partnership between English musicians John Lennon (1940–1980) and Paul McCartney of the Beatles. It is widely considered one of the greatest, best known and most successful musical collaborations ever by records sold, with the Beatles selling over 600 million records worldwide as of 2004. Between 5 October 1962 and 8 May 1970, the partnership published approximately 180 jointly credited songs, of which the vast majority were recorded by the Beatles, forming the bulk of their catalogue.

A songwriter is a musician who professionally composes musical compositions or writes lyrics for songs, or both. The writer of the music for a song can be called a composer, although this term tends to be used mainly in the classical music genre and film scoring. A songwriter who mainly writes the lyrics for a song is referred to as a lyricist. The pressure from the music industry to produce popular hits means that song writing is often an activity for which the tasks are distributed among a number of people. For example, a songwriter who excels at writing lyrics might be paired with a songwriter with the task of creating original melodies. Pop songs may be composed by group members from the band or by staff writers – songwriters directly employed by music publishers. Some songwriters serve as their own music publishers, while others have external publishers.