The Facebook of today—and tomorrow—is far more expansive than it was just a few years ago. It’s easy to forget that when the company filed to go public on February 1, 2012, it was just a single website and an app that the experts weren’t sure could ever be profitable. Now, “a billion and a half people use the main, core Facebook service, and that’s growing. But 900 million people use WhatsApp, and that’s an important part of the whole ecosystem now,” Zuckerberg says. “Four hundred million people use Instagram, 700 million people use Messenger, and 700 million people use Groups. Increasingly, we’re just going to go more and more in this direction.” Read more at Fast Company.