"Kickstart My Heart" is about all the ways Motley Crue gets their blood flowing without drugs. It was inspired by their bass player Nikki Sixx, who claimed he had to be revived with a shot of adrenaline to the heart after an overdose.
John Legend wrote "All Of Me" about his fiancée Chrissy Teigen. He sang it to her at their wedding ceremony in Como, Italy.
The voice of Waldo in Van Halen's "Hot For Teacher" video was the late Phil Hartman of Saturday Night Live Fame.
Lucinda Williams' track "Compassion" is based on a poem by her father, lauded Arkansas poet Miller Williams.
The Kate Bush song "Why Should I Love You?" is a collaboration with Prince. He completely re-worked her demo, so Bush spent a lot of time piecing it back together to keep her imprint.
"Irreplaceable" wasn't specifically penned for Beyonce - in fact, Ne-Yo wrote it more as a country song and had Faith Hill and Shania Twain in mind.
When he was asked to write a song for the Singles soundtrack, Mark thought the Seattle grunge scene was already overblown, so that's what he wrote about.
Martyn talks about producing Tina Turner, some Heaven 17 hits, and his work with the British Electric Foundation.
Rise Against frontman Tim McIlrath explains the meanings behind some of their biggest songs and names the sci-fi books that have influenced him.
Dokken frontman Don Dokken explains what broke up the band at the height of their success in the late '80s, and talks about the botched surgery that paralyzed his right arm.
An original member of Depeche Mode, Vince went on to form Erasure and Yaz.
On Glen's résumé: hit songwriter, Facebook dominator, and member of Styx.