39. Kevin Systrom
Kevin Systrom
CEO, Instagram
Age: 27
Industry: Technology

Having launched only a year ago, "Instagram" is already part of the general lexicon. The multipurpose app -- it alters photos, organizes them, and enables a wide range of sharing options on its own Twitter-like network -- has quickly amassed 11 million users. By the nine-month point, users had shared 150 million pictures. Systrom co-founded the company with Mike Krieger after he joined Systrom's previous mobile sharing app, Burbn.

Tech in the genes: Systrom's mother worked at Monster.com during the first startup boom, and now she's a category director at Zipcar.

Last updated October 25 2011: 5:11 PM ET
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