The Harvard dropout who changed what it means to be social by creating global neighborhood Facebook will add to his Silicon Valley legend this week by riding the company to a historic Wall Street debut.
Eight years after launching Facebook from his university dorm room, Mark Zuckerberg has evolved from an awkward public speaker into a confident chief executive presiding over an online community that, in the words of Time magazine, is "transforming the way we live our lives every day."
One thing that hasn't changed over the years is Zuckerberg's look -- despite a personal fortune projected to catapult above $28 billion based on shares of stock he will hold after Facebook goes public.
Zuckerberg still favors t-shirts, jeans and sneakers, his trademark hoodie and a mop of brown, curly hair.
His casual style of dressing has nettled members of the suit-wearing financial community in the weeks leading up to Facebook's initial public offering, but company insiders recount how hard it was to get him to give up wearing sandals to work.
Wearing a tie daily became one of the annual goals that Zuckerberg sets for himself as a way of expanding his life to include more than just work.
In 2011, it was to become a vegetarian and "only eat meat if I kill the animal myself."
In 2010, it was to learn Chinese. "Some members of my girlfriend's family only speak Chinese and I wanted to be able to talk to them," he said.
Zuckerberg will reportedly ring the Nasdaq opening bell remotely from Facebook's new campus in the northern California city of Menlo Park on Friday, kicking off the largest IPO ever by an Internet firm. Facebook is to keep slightly more than half of the $10.6 billion raised from stock sales.
The IPO is structured to keep control of Facebook in the hands of Zuckerberg, who has been the subject of a Hollywood blockbuster, Time's "Person of the Year" and cracked the Forbes list of 20 richest people in the world -- all before the age of 28.
Born on May 14, 1984, Zuckerberg was raised in Dobbs Ferry outside New York, one of four children of a dentist father and a psychiatrist mother.
Zuckerberg began writing computer programs at the age of 11 including one said to resemble Pandora's musical taste program which reportedly drew the interest of AOL and Microsoft.
He went to high school at the prestigious Phillips Exeter Academy, where he was captain of the fencing team, before entering elite Harvard University.
Zuckerberg launched Thefacebook.com, as it was then known, from his Harvard dorm room on February 4, 2004 with roommates and classmates Dustin Moskovitz, Chris Hughes and Eduardo Saverin.
The stated goal: "Making the world more open and connected."
Facebook's origins were not without controversy, however.
In 2008, a $65 million settlement was reached with three Harvard classmates -- twins Tyler and Cameron Winklevoss and Divya Narendra -- over their charges that Zuckerberg had stolen the idea for Facebook from them.
The conflict was at the heart of "The Social Network," the Oscar-winning film written by Aaron Sorkin and directed by David Fincher.
Zuckerberg left Harvard in May 2004 for Silicon Valley, where he received his first major funding -- $500,000 -- from PayPal co-founder Peter Thiel followed by nearly $13 million the next year from Accel Partners.
Despite recurring privacy complaints, Facebook has gone from strength to strength, growing from 50 million members in 2007 to more than 900 million today.
Zuckerberg's Facebook page, which has attracted 13 million fans, contains pictures of his girlfriend, Priscilla Chan; his dog, Beast, and co-workers. His "likes" include the band "Linkin Park" and the documentary "Waiting for Superman."
Zuckerberg has been referred to by some as being struck in the mold of Apple co-founder Steve Jobs, who died last year of cancer. Zuckerberg has praised Jobs as a friend and a role model.
Similarities between the men include not being afraid to risk falling while chasing big dreams, according to Creative Strategies principal analyst Tim Bajarin.
"He has the Silicon Valley DNA that you can't be afraid to fail," Bajarin said of Zuckerberg.
"Another thing that is very much Steve Jobs is he has a vision and he follows that vision no matter what anybody else says."