Hey Jude

"Hey Jude" is a song by English pop-rock group The Beatles. It was written by Paul McCartney. It started as "Hey Jules", a song McCartney wrote for John Lennon's son, Julian, during his parents' divorce.
"Hey Jude" was released in August 1968. It is over seven minutes in length. At the time, this was the longest single ever to top British music charts.
The song is well known for it's sing-a-long ending. Paul McCartney leads a large crowd in song, they are singing together. What they are singing is a simple melody with very simple lyrics over and over. This part of the song has just three words. First the sound "na" is repeated many times, and then come the words "hey Jude." In English, "na" has no meaning, it is just a sound to sing with your voice.