Kevin Systrom turned down a job from Mark Zuckerberg in college, shared a desk with Jack Dorsey as an intern at what became Twitter. Then in 2010 launched Instagram as we know it. Just two years later he reunited with Zuckerberg and made Silicon Valley history agreeing to sell Instagram to Facebook for a billion dollars. The company had just 13 employees and just 30million users. Today over half a billion on the planet use Instagram every month sharing more than 95 million photos and videos a day.