Faces of Facebook: Who's Who in 'The Social Network'?

Oct. 1, 2010— -- Mark Zuckerberg may the biggest face attached to Facebook, but he's not the only one. "The Social Network," the controversial story about the world's most powerful social network, has a colorful cast of characters -- on screen and off.

This weekend, "The Social Network," the highly-anticipated movie about Facebook's founding, opens in theaters around the country to give movie fans Hollywood's take on the college kids and computer crackerjacks behind the wildly-successful website.

It is based on a book that is widely understood (at the very least) to be dramatized. Zuckerberg himself told ABC News that the movie is "fiction."

Still, though some of the movie's events may be in dispute, the characters are real.

If you want to learn a bit more about the faces behind Facebook, take a look below.

The man of the moment, Mark Zuckerberg, is the 26-year-old billionaire who founded Facebook from his Harvard dorm room in 2004. As if the new movie wasn't already shining a bright enough spotlight on the young CEO, Zuckerberg set tongues wagging last week when he announced a $100 million charitable donation to public schools.

The movie depicts him as a girl-crazy computer nerd desperate to gain access to the university's refined and exclusive social clubs. But some in Silicon Valley say Zuckerberg, who grew up in Dobbs Ferry, N.Y., is motivated by data, not dating.

"From the beginning, what fascinated him about Facebook was having the sheer efficiency ... taking all that complex data and making it, within seconds, work for you," Sarah Lacy, a longtime Silicon Valley reporter and author of "Once You're Lucky, Twice You're Good," told ABCNews.com in a June 2009 interview.

According to a recent New Yorker profile on Zuckerberg, he has been dating his current girlfriend, Priscilla Chan, since 2003, with a short interruption. In a recent interview with Oprah Winfrey, he let cameras videotape the modest home he shares with Chan in Palo Alto, Calif., and said she played an influential role in his decision to fund public schools.

Forbes Magazine last week released its list of the 400 richest Americans and ranked Zuckerberg 35th, ahead of even Apple's CEO, Steve Jobs, with an estimated worth of $6.9 billion.