Today, Facebook is one of the most-used websites on the Internet, visited by millions of users each day and home to more than 500 million accounts. Many people use Facebook to share pictures, news, and ideas with friends—but they may not know the true story behind Facebook's massive success. Facebook began as the idea of one college student: Mark Zuckerberg. Discover how Mark founded one of the most successful social networking sites on the Internet while he was still in school. Learn how he first got Facebook growing, and how he keeps millions of people logging in day after day. Find out more about the man behind Facebook—and learn what's next for his company.