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Mark Zuckerberg is an American technology executive and computer programmer who cofounded the social networking site Facebook. Zuckerberg is chief executive officer (2004– ) of both Facebook and its parent company Meta Platforms, Inc. (META).
Mark Elliot Zuckerberg was born on May 14, 1984, in White Plains, New York, to Edward Zuckerberg, a dentist, and Karen Kempner-Zuckerberg, a psychiatrist. He grew up in nearby Dobbs Ferry with three sisters: Randi, Donna, and Arielle.
His father operated a dental practice from the family home, where computers were part of Zuckerberg’s life from an early age. At about age 11, Zuckerberg created a home messaging network called ZuckNet that allowed his family to send messages between computers. After attending Phillips Exeter Academy, Zuckerberg enrolled at Harvard University in 2002.
On February 4, 2004, Zuckerberg and Eduardo Saverin launched thefacebook.com (renamed Facebook in 2005), a directory in which fellow Harvard students entered their own information and photos into a template that Zuckerberg had devised.
Within two weeks, half of the student body had signed up. Zuckerberg’s roommates Dustin Moskovitz and Chris Hughes helped him to add features and make the site available to other campuses nationwide. Facebook quickly became popular as registered users could create profiles, upload photos and other media, and keep in touch with friends.
Facebook differed from other social networking sites, however, in its emphasis on real names (and email addresses), or “trusted connections.” It also laid particular emphasis on networking, with information disseminated not only to each individual’s network of friends but also to friends of friends—what Zuckerberg called the “social graph.”
In the summer of 2004, Facebook’s operations were moved to Palo Alto, California, where Zuckerberg secured seed funding from venture capitalist Peter Thiel. Zuckerberg dropped out of Harvard to concentrate on the fledgling company, becoming its CEO and president.
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In May 2005, Facebook received its first major infusion of venture capital ($12.7 million). Four months later, Facebook opened to registration by high-school students. Meanwhile, foreign colleges and universities also began to sign up, and by September 2006 anyone with an e-mail address could join a regional network based on where he or she lived.
At about that time, Zuckerberg turned down a $1 billion buyout offer from Yahoo!, but in 2007 Facebook struck a deal with Microsoft (MSFT) in which the software company paid $240 million for a 1.6% stake in Facebook; two years later Digital Sky Technologies purchased a 1.96% share for $200 million.
Facebook held its initial public offering (IPO) in 2012, one of the largest technology IPOs in U.S. history, cementing Zuckerberg’s position as one of the world’s most prominent technology executives.

In October 2021, Facebook changed the name of its parent company to Meta Platforms (META). The name change reflected an emphasis on the metaverse, in which users would interact in virtual reality environments.
Meta’s investment in the metaverse proved costly, with its Reality Labs division accumulating more than $80 billion in operating losses from late 2020 through mid-2026. The company also struggled to attract users to its virtual reality products. Beginning in 2023, Zuckerberg shifted Meta’s attention toward generative artificial intelligence and AI-powered tools, while continuing to invest in virtual reality.
AI increasingly became a focus of Zuckerberg’s leadership at Meta. For 2026, the company forecast capital expenditures of $135 billion to $145 billion, including investments in AI infrastructure and data centers, as it sought to compete with other leading AI developers.
In August, Zuckerberg outlined his vision for what he called “personal superintelligence,” arguing that advanced AI should be widely accessible rather than controlled by a small number of companies or governments. He reaffirmed Meta’s commitment to developing open-source AI models that others could download, modify, and run independently.
In October 2026, Zuckerberg reached an agreement with Meta’s board that would allow him to sell shares of a new class of nonvoting stock without relinquishing voting control of the company. The arrangement was intended to help him meet potential tax obligations under a proposed California tax on billionaires. The new shares would also give Meta greater flexibility to raise capital for its AI investments.
In the 2000s and 2010s, Zuckerberg spoke publicly about issues such as U.S. immigration policies and social justice. His immigration reform group Fwd.US criticized mass deportation of undocumented immigrants in 2015, and Zuckerberg himself endorsed broadly liberal policies.
After Donald Trump won the 2016 presidential election, Facebook faced criticism over the spread of political misinformation on the site. In response, Zuckerberg committed Facebook to greater efforts to combat misinformation, including working with independent fact-checking organizations.
On January 6, 2021, a mob of Trump supporters stormed the U.S. Capitol in an attempt to prevent the certification of Pres. Joe Biden’s victory. Facebook and Instagram subsequently banned Trump, citing his posts during the violence and the risk of further violence.
In January 2023, Trump’s accounts were reinstated, but with restrictions in place to “deter repeat offenses.” The restrictions were temporary and were removed in July 2024. In an August 2024 letter, Zuckerberg criticized the Biden administration’s efforts to persuade Facebook to restrict COVID-19 misinformation during the pandemic, saying that he believed the “government pressure was wrong.”
After Trump’s second presidential victory in November 2024, Zuckerberg congratulated him. In December, Meta donated $1 million to Trump’s inaugural fund. In January 2025, Meta ended its fact-checking program in the United States on Facebook and Instagram, a move Zuckerberg said would help the company “get back to its roots around free expression.”
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