It's hard to imagine a more modern billionaire than Mark Zuckerberg. He may occasionally come in for some bad press, but he invented Facebook. His creation has changed the way we connect with people.
Zuckerberg has been with Priscilla Chan since they met at Harvard. They got married back in 2012 in a surprisingly low-key wedding. While he got busy on the internet, she became a pediatrician. She also manages the multi-billion-dollar Chan Zuckerberg Initiative charity, which has raised over $45bn for good causes.