Here are some billionaires that dropped out of college to pursue their ambitions elsewhere.

College is a major stepping stone for most of the world’s success stories. That being said, college isn’t for everyone, including some of the biggest names in the business world.

The first example that most people would have heard of is Facebook CEO Mark Zuckerberg. Zuckerberg created the social network while he was still at Harvard. The creation was initially meant to help his fellow students learn more about each other, but he dropped out shortly after launching it. After dropping out of Harvard, Zuckerberg continued down his path with the social network and he’s now worth an estimated $66 billion.

The founder of Oracle, Larry Ellison, dropped out of two different colleges. He dropped out of the University of Illinois after his adoptive mother died, then he dropped out of the University of Chicago after just one semester. The 75-year-old is now worth about $63 billion.

Uber’s current CEO and co-founder of the company Travis Kalanick also dropped out of college before striking gold. Kalanick studied computer engineering at UCLA before moving on to work on a search engine called Scour. That project didn’t end up working too well, so after Scour filed for bankruptcy, Kalanick founded Red Swoosh, a networking-software company. He went on to sell Red Swoosh for $23 million in 2007 before traveling the world for a year, after which he founded Uber. Kalanick is now worth about $3.7 billion.