Sergey Brin, 31, President, Technology & Co-Founder, Google ($4.17 billion)

Sergey Brin, co-founder of the phenomenally successful Internet search engine Google, closely follows his friend Larry Page at No. 5 on the Fortune '40 under 40' list.

Brin, a native of Moscow, received a bachelor of science degree with honors in mathematics and computer science from the University of Maryland at College Park. He is currently on leave from the PhD programme in computer science at Stanford University, where he received his master's degree.

Brin is a recipient of a National Science Foundation Graduate Fellowship as well as an honorary MBA from Instituto de Empresa.

It was at Stanford that he met Larry Page and worked on the project that became Google. Together they founded Google Inc. in 1998, and Brin continues to share responsibility for day-to-day operations with Larry Page and Eric Schmidt.

Photograph: Justin Sullivan/Getty Images

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