Feist's "1234" is "about lost love, and the hope to recapture what you once had," but it's best known for the Sesame Street version about counting to four.
The line, "Gotta keep 'em separated" in "Come Out And Play" by The Offspring came to lead singer Dexter Holland when he was a medical student and needed to keep bacteria samples away from each other.
"Just Dance" was Lady Gaga's first hit, and it also brought the techno-synth sound that had been popular in Europe for the previous decade to the United States.
Mike Nesmith wrote Linda Ronstadt's first hit, "Different Drum," before he joined The Monkees. He played an intentionally bad version of it on the show.
"Hunger Strike" by Temple of the Dog features Chris Cornell and Eddie Vedder, and was Vedder's first music video.
Just how much did these monsters of rock dabble in the occult?
Did Eric Clapton really write "Cocaine" while on cocaine? This question and more in the Clapton edition of Fact or Fiction.
Medley looks back on "Unchained Melody" and "You've Lost That Lovin' Feelin'" - his huge hits from the '60s that were later revived in movies.
A history of songs dealing with transgender issues, featuring Pink Floyd, David Bowie, Morrissey and Green Day.
These overtly religious songs crossed over to the pop charts, despite resistance from fans, and in many cases, churches.