Hank Green (co-founder of DFTBA.com) started making YouTube videos with his brother almost 20 years ago. Now he’s a go-to internet science guy, having produced and hosted thousands of videos and podcasts. He’s also an author, stand-up comedian, and entrepreneur, having co-founded Focus Friend (Google’s App of the Year), Good.Store (which donates all profit to charity), and, of course, Complexly, which produces SciShow, Crash Course, and nearly a dozen other educational YouTube channels.