"And I Love Her" is a song recorded by English rock band the Beatles, written mainly by Paul McCartney (credited to Lennon–McCartney). Being the fifth track on their third album, A Hard Day's Night, it was released 20 July 1964 with "If I Fell" as a single by Capitol Records in the United States, reaching No. 12 on the Billboard Hot 100.

The Beatles performed "And I Love Her" just once outside Abbey Road Studios; on 14 July 1964 they played it for an edition of the BBC's Top Gear radio show, which was broadcast two days later.

A majority of the composition modulates back and forth between the key of E and its relative minor C#m. It also changes keys altogether just before the solo, to Gm. It ends on the parallel major of the key of F's relative minor, D. This technique is known as Picardy third resolution.

The song was written mainly by McCartney, though John Lennon claimed in an interview with Playboy that his major contribution was the middle eight section ("A love like ours/Could never die/As long as I/Have you near me").

Beatles publisher Dick James lends support to this claim, saying that the middle eight was added during recording at the suggestion of producer George Martin (an early take of the song was released on Anthology 1 in 1995, and the middle eight had not yet been added). According to James, Lennon called for a break and "within half an hour [Lennon and McCartney] wrote...a very constructive middle to a very commercial song." McCartney, on the other hand, maintains that "the middle eight is mine.... I wrote this on my own. I would say that John probably helped with the middle eight, but he can't say 'It's mine'."

...
Wikipedia