Zuckerberg hasn't shied away from giving back. In fact, last year he was the second-most generous giver in the United States, according to the Chronicle of Philanthropy.
He doesn't have any direct personal ties to Newark, N.J. But in 2010, he pledged a whopping $100 million of his fortune to helping out troubled schools there.
The money was the first gift from Startup: Education, a foundation created by Zuckerberg to help schools. Joined by Booker and Christie, Zuckerberg took to "The Oprah Winfrey Show" to announce the donation and foundation.
Cynics noted that the gift came shortly before the release of "The Social Network," the fictionalized film on Facebook's birth that many believed cast Zuckerberg in a negative light.
But his philanthropy didn't stop there. Zuckerberg later pledged an even bigger sum, nearly $500 million, to the Silicon Valley Community Foundation, which issues grants for a host of causes in the San Francisco area. In 2012, its charitable causes ranged from programs that teach immigrants English to groups providing food and shelter to the needy to funds for victims of the California wildfires.