Sergey Brin (Google)

Sergey mentioned how he didn't have too many friends when he was at Stanford and liked athletic classes the most.

The Brins’ story provides me with a clue to the origins of Sergey’s entrepreneurial instincts. His parents, academics through and through, deny any role in forming their son’s considerable business acumen—“He did not learn it from us, absolutely not our area,” Michael says. Yet Sergey’s willingness to take risks, his sense of whom to trust and ask for help, his vision to see something better and the conviction to go after it—these traits are evident in much of what Michael Brin did in circumventing the system and working twice as hard as others to earn his doctorate, then leave the Soviet Union.
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Sergey's father: "also began to teach himself computer programming, having no expectation of getting an academic position if they ever got out." [Lesson: teaching yourself programming is doable; it isn't a crazy endeavor]
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When I ask about her former pupil, Barshay lights up, obviously proud of Sergey’s achievements. “Sergey wasn’t a particularly outgoing child,” she says, “but he always had the self-confidence to pursue what he had his mind set on.”

He gravitated toward puzzles, maps and math games that taught multiplication. “I really enjoyed the Montessori method,” he tells me. “I could grow at my own pace.” He adds that the Montessori environment—which gives students the freedom to choose activities that suit their interests—helped foster his creativity. [This reminds me of the way I've been teaching myself finance / programming / mathematics / entrepreneurship, which has involved a lot more meandering than a typical college curriculum.]

“He was interested in everything,” Barshay says, but adds, “I never thought he was any brighter than anyone else.”
[Lesson: You may have exceptional potential even if no one recognizes it except you.]
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Sergey attended Eleanor Roosevelt High School, a large public school in Greenbelt. He raced through in three years, amassing a year’s worth of college credits that would enable him to finish college in three years as well. At the University of Maryland, he majored in mathematics and computer science and graduated near the top of his class.
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Personable, with an easy smile, Sergey brims with a healthy self-assuredness that at times spills over into arrogance. At Stanford, he was known for his habit of bursting in on professors without knocking. One of his advisers, Rajeev Motwani, recalls, “He was the brash young man. But he was so smart, it just oozed out of him.” 
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Like Sergey, Larry is the son of high-powered intellects steeped in computer science. His father, Carl Victor Page, a computer science professor at Michigan State University until his death in 1996, received one of the first Ph.D.s awarded in the field. His mother, Gloria, holds a master’s degree in computer science and has taught college programming classes.
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Larry and Sergey soon began working on ways to harness information on the World Wide Web, spending so much time together that they took on a joint identity, “LarryandSergey.”
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Calling their new invention Google—a misspelling of a very large number in mathematics—Larry and Sergey shopped it around to various companies for the price of $1 million.

No one was interested. In the technology boom of the late 1990s, conventional thinking was that so-called web portals like Yahoo! and AOL, which offered email, news, weather and more, would make the most money. No one cared about search. But Sergey and Larry knew they were on to something, so they decided to take leaves of absence from Stanford and build a company themselves. Sergey’s parents were skeptical. “We were definitely upset,” Genia says. “We thought everybody in their right mind ought to get a Ph.D.”

Soliciting funds from faculty members, family and friends, Sergey and Larry scraped together enough to buy some servers and rent that famous garage in Menlo Park. Their venture quickly bore fruit: After viewing a quick demo, Sun Microsystems cofounder Andy Bechtolsheim (himself a Jewish immigrant from Germany) wrote a $100,000 check to “Google, Inc.”
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Sergey: “I don’t feel comfortable being one of the crowd,” he reflects. “It’s kind of interesting—I really liked the schools that I went to, but I never rooted for the sports teams. I was never one of the crowd supporting something or not. I like to maintain my independence.”
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Larry took the podium first, urging the students to maintain a “healthy disregard for the impossible,” a favorite Google phrase. When it was Sergey’s turn to speak, he began, to the crowd’s delight, with a few words in Russian, which he still speaks at home with his parents.

“I have standard Russian-Jewish parents,” he then continued in English. “My dad is a math professor. They have a certain attitude about studies. And I think I can relate that here, because I was told that your school recently got seven out of the top 10 places in a math competition throughout all Israel.”

The students applauded their achievement and the recognition from Sergey, unaware that he was setting up a joke. “What I have to say,” he continued, “is in the words of my father: ‘What about the other three?’”

...I've come to recognize that the challenge of a problem or the importance isn't that related to how likely you are to achieve it.[...] [Going after an ambitious goal] is a little bit harder, but you bring so much passion that you're more likely to succeed. [Larry Page has said the same thing in a speech given to the Academy of Achievement]