Justin Bieber
In 2007, Bieber became the poster child of what social media can do when he was discovered by his manager, Scooter Braun, on YouTube. The singer was known by his small YouTube following as kidrauhl, a 13-year-old aspiring musician who posted covers of hits like Chris Brown’s “With You.” The covers quickly led to a meeting with Usher and a recording contract, and the rest is history.