3. Mark Zuckerberg, 33, is the founder and CEO of Facebook. The Zuckerberg-led social network is used by billions of people and has turned him into the fifth richest person in the world.
4. Sebastian Kurz, 31, is leader of the conservative Austrian People's Party and is expected to become the next chancellor of Austria. When he takes over as chancellor, Kurz will become the youngest national leader in the world.
10. Sam Altman, 32, is the president of Y Combinator, Silicon Valley's largest startup incubator. Altman has laid out his vision of tech-powered future, and is commenting more frequently on politics and his plan for the US's future.
11. LeBron James, 32, is one of the most dominant athletes in the world. The star basketball player has comically lampooned his own image on TV and in movies, and is outspoken on social and political issues.