After 47 visits to the Hot 100, Justin Bieber topped the tally for the first time on September 17, 2015 with "What Do You Mean?"
"All Star" was written as a confidence builder for fans who were bullied for liking Smash Mouth.
"Walking on a Thin Line" by Huey Lewis and the News is about an American soldier who is trained as a sniper in the Vietnam War. It was written for a documentary on the war.
"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 Pretenders are named after the 1956 song "The Great Pretender" by The Platters.
Janet Jackson wrote the lyric to "Nasty" in response to random guys calling her "baby."
Switchfoot's frontman and main songwriter on what inspires the songs and how he got the freedom to say exactly what he means.
What's the deal with "Summer of '69"? Bryan explains what the song is really about, and shares more of his songwriting insights.
The Red Hot Chili Peppers have some rather unusual song titles - see if you can spot the real ones.
Dean wrote the screenplay and lyrics to all the songs in Footloose. His other hits include "Fame" and "All The Man That I Need."
Dave reveals the inspiration for "Feelin' Alright" and explains how the first song he ever wrote became the biggest hit for his band Traffic.
Daryl Hall's TV show is a hit, and he's been inducted into the Rock and Roll Hall of Fame - only one of these developments excites him.