Jack & Jack

Affectionately known as the Jacks, the young pop-rap duo Jack & Jack used video-sharing sites, music-sharing sites, and other bits of social media to launch their career in 2014. Friends since kindergarten, Jack Gilinsky and Jack Johnson gained a loyal following thanks to a series of short comedic videos they uploaded to the Web in 2013. Music came a year later, first with the laid-back track "Distance" and then with the party cut "Wild Life." The latter climbed into the U.S. Billboard Hot 100 that summer, a summer that was also the duo's first as high-school graduates. In 201...