Mark Elliot Zuckerberg (born May 14, 1984) is an American media magnate, internet entrepreneur, and philanthropist. He is known for co-founding Facebook, Inc. and serves as its chairman, chief executive officer, and controlling shareholder. He also is a co-founder of the solar sail spacecraft development project Breakthrough Starshot and serves as one of its board members. Zuckerberg attended Harvard University, where he launched the Facebook social networking service from his dormitory room on February 4, 2004. Originally launched to select college campuses, the site expanded rapidly and eventually beyond colleges, reaching one billion users by 2012. Zuckerberg took the company public in May 2012 with majority shares. His net worth is estimated to be nearly $54 billion as of March 2020. In 2007, at age 23, he became the world's youngest self-made billionaire. As of 2019, and the only one under 40 in the Top 20 Billionaires list. Since 2010, Time magazine has named Zuckerberg among the 100 wealthiest and most influential people in the world as a part of its Person of the Year award. In December 2016, Zuckerberg was ranked 10th on Forbes list of The World's Most Powerful People.

Zuckerberg was born on May 14, 1984, in White Plains, New York. His parents are Karen (née Kempner), a psychiatrist, and Edward Zuckerberg, a dentist. He and his three sisters, Randi, Donna, and Arielle, were brought up in Dobbs Ferry, New York, a small Westchester County village about 21 miles north of Midtown Manhattan. Zuckerberg was raised in a Reform Jewish household, and his ancestors hailed from Germany, Austria and Poland. He had a Star Wars-themed bar mitzvah when he turned 13. At Ardsley High School, Zuckerberg excelled in classes. After two years, he transferred to the private school Phillips Exeter Academy, where he won prizes in mathematics, astronomy, physics, and classical studies. In his youth, he also attended the Johns Hopkins Center for Talented Youth summer camp. On his college application, Zuckerberg stated that he could read and write French, Hebrew, Latin, and ancient Greek. He was captain of the fencing team.