"Jessie's Girl" tells the true story of a girl Rick Springfield was crushing on, but her boyfriend's name was really Gary and he was more of an acquaintance than a friend.
Tina Turner hated "What's Love Got To Do With It" but when her manager convinced her to record it anyway, it became her big comeback hit.
Justin Timberlake originally wrote "Gone" for Michael Jackson, but his team turned it down, so 'N Sync cut it instead.
"A Hard Day's Night" was the title song to The Beatles' first movie, which was surprisingly good: it was nominated for two Oscars.
The video for Iggy Azalea's "Fancy" pays homage to the classic 1995 film Clueless with the rapper playing Cher and featured singer Charli XCX portraying Tai. It was filmed at some of the same locations used in the movie.
Pink Floyd's "Shine On You Crazy Diamond" is about their founding member Syd Barrett, who became an acid casualty. Notice the S-Y-D in the title.
Before "Rap" was a form of music, it was something guys did to pick up girls in nightclubs. Donnie talks about "The Rapper" and reveals the identity of Leah.
The former Metallica bassist talks about his first time writing a song with James Hetfield, and how a hand-me-down iPad has changed his songwriting.
Fishbone has always enjoyed much more acclaim than popularity - Angelo might know why.
Eddie (played by Johnny Depp in the video) found fame fleeting, but Chuck Berry's made-up musician fared better.
The top chant artist in the Western world, Krishna Das talks about how these Hindu mantras compare to Christian worship songs.
Dave reveals the inspiration for "Feelin' Alright" and explains how the first song he ever wrote became the biggest hit for his band Traffic.