Moonlight Bay is a traditional song, first published in 1912 and credited to Percy Wenrich (music) and Edward Madden (lyrics). It became more widely popular after Alice Faye sang it in Tin Pan Alley, a 1940 film. The first line is "We were sailing along, on Moonlight Bay . . ."
The Beatles sang a short, somewhat improvised version of this old classic during an appearance on the (Eric) Morecambe and (Ernie) Wise television show in December of 1963. They were in the ATV Studios (Borehamwood). On this program they performed This Boy and I Want to Hold Your Hand. Then they were joined by the hosts of the program for what might have seemed to be an impromptu rendition of Moonlight Bay, except that the Beatles put on boater hats and white jackets with stripes, while Eric Morecambe put on a Beatle wig and collarless jacket. In a spirit of good fun, he added spoken phrases after each line of the song, like "twist and shout" and "woo-woo." This performance was recovered from archival tapes and provided to the public in the Anthology 1 collection.