The song is based on a blues-rock harmonic structure, primarily using the blues scale and a repetitive chord progression.
The rhythm is characterized by a slow, deliberate tempo and a heavy, syncopated groove.
The melody is blues-influenced, with John Lennon's vocals delivering the cryptic lyrics in a relaxed and somewhat understated manner.
The song originated from a campaign slogan for Timothy Leary's run for governor of California.
Serving as the opening track of the iconic 'Abbey Road' album, this song represents The Beatles' shift toward a heavier, more sophisticated studio sound. Its minimalist arrangement and swampy groove solidified its place as one of the most covered and enduring tracks in rock history.