LOS ANGELES, CA - JULY 27:  Singer-songwriter Justin Bieber attends the 2014 Young Hollywood Awards brought to you by Samsung Galaxy at The Wiltern on July 27, 2014 in Los Angeles, California.  (Photo by Ari Perilstein/Getty Images for Variety)

Justin Bieber

Singer/Rapper

Gaining fame via Youtube, this self-taught singer became a teen idol at the speed of DSL. Raised by a young single mother, the Canadian-born teenager was mentored by R&B superstar Usher, with whom he performed live on the 2011 Grammy Awards. Bieber released his debut album, My World in 2009, which spawned no fewer than seven hit singles. He is now a certified pop phenomenon, rocking stages and the silver screen with his hit 3D concert film Justin Bieber: Never Say Never. (Photo: Ari Perilstein/Getty Images for Variety)