Paul McCartney's favorite song that he wrote for someone else is Cilla Black's 1968 UK Top 10 hit, "Step Inside Love."
Steely Dan's engineer, Roger Nichols, built one of the first drum machines, which they used on "Hey Nineteen."
Paul McCartney wrote "Hey Jude" to comfort John Lennon's 5-year-old son Julian, whose parents were getting a divorce.
John Lennon wrote "The Continuing Story of Bungalow Bill" about Richard Cooke, a hunter he met at the Maharishi's camp in India. Cooke hasn't shot anything since the camp, except with his camera - he became a freelance photographer for National Geographic.
The lyrics for Lesley Gore's "It's My Party" were based on actual events relating to his daughter Judy's sweet 16 party. The teenager threw a tantrum and burst into tears when her mum and dad insisted that her grandparents had to be invited.
"Grenade" was a term used on the show Jersey Shore to mean an ugly girl. Bruno Mars says his hit song with that title was written before the show started.
The 10 biggest "retirement tours" that didn't take.
Beef with Bon Jovi? An unfortunate Spandex period? See if you can spot the true stories in this Metallica version of Fact or Fiction.
Can you be married in one country but not another? Only if you're part of a gay couple. One of the first famous singers to come out as a lesbian, Janis wrote a song about it.
Was Janet secretly married at 18? Did she gain 60 pounds for a movie role that went to Mariah Carey? See what you know about Ms. Jackson.