2012 witnessed the rise of several Internet entrepreneurs who tapped into the power of social media and online marketing to reach a massive audience. Pinterest was easily among the most popular and fastest growing social networking tool of the year. The photo-sharing networking tool was launched in March 2010 by Paul Sciarra and Ben Silbermann. Silbermann, in an effort to be interactive with users, personally wrote to the first 5,000 users with his phone number for any questions they may have. After nine months of its launch, Pinterest attracted 10,000 users. Despite a rough start, Silbermann and Sciarra continued to improve user experience on Pinterest rather than accept defeat—their efforts have paid off.

Instagram was launched in October 2010, which happened to perfectly coincide with the release of the iPhone 4. Instagram is an online photo-sharing and social networking service that enables its users to take a picture, apply a digital filter to it, and share it on a variety of social networking services, including its own. The brainchild of Instagram is Kevin Systrom—he graduated from Stanford with a B.S. in management science and engineering, the perfect storm. After three months of its launch date, Instagram boasted 3 million users. The icing on the cake for Instagram? Facebook acquired the photo-sharing tool in April 2012 for $1 billion. As of September 2012, Instagram had a following of 100 million users.

The masterminds behind Twitter, Turntable, and RockMelt also made the list of the top Internet entrepreneurs of 2012. Check out the infographic below to learn more!

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