Age: 25
Occupation: Musician, producer
Previous TIME 100 appearances: 0
Since signing with Elektra Records in 2009, Bruno Mars has made a name for himself by writing the undeniably catchy hooks on songs such as B.o.B's "Nothin' on You," Travie McCoy's "Billionaire" and Cee Lo Green's "F--- You!" His 2010 album, Doo-Wops & Hooligans, reached No. 3 on the Billboard 200. No wonder he was nominated for seven Grammys this year.