"Girl Crush" by Little Big Town came from the hashtag #girlcrush, which its co-writer, Lori McKenna, spotted on Instagram.
Jeff Lynne sang the word "groose" in the chorus of "Don't Bring Me Down" as a nonsense placeholder, but left it in when he found out it means "greetings" in German ("gruss").
"Brad Paisley's "River Bank" was inspired by his childhood growing up 500 yards from the Ohio River.
Public Enemy didn't appreciate the Bobby McFerrin hit 'Don't Worry, Be Happy." in "Fight The Power," Chuck D raps, "damn if I say it you can slap me right here."
Lyrically, Elvis Costello's "Watching The Detectives" was inspired by American detective shows; musically, it was inspired by The Clash.
The dirty version of Cee-Lo Green's "Forget You" contains 16 F-bombs. He recorded a clean version as an afterthought, "just in case."
Yngwie Malmsteen and Steve Vai were two of Graham's co-writers for some '80s rock classics.
Scaramouch, a hoople and a superhero soundtrack - see if you can spot the real Queen stories.
Bob was the bass player and lyricist for the first two Ozzy Osbourne albums. Here's how he wrote songs like "Crazy Train" and "Mr. Crowley" with Ozzy and Randy Rhoads.
What happens when Kurt Cobain, Iron Maiden and Johnny Lydon are told to lip-synch? Some hilarious "performances."
Dave reveals the inspiration for "Feelin' Alright" and explains how the first song he ever wrote became the biggest hit for his band Traffic.
Jon Fratelli talks about the band's third album, and the five-year break leading up to it.