With a personal fortune estimated at $96 billion, Bill Gates is the world’s second wealthiest person, ahead of Facebook’s Mark Zuckerberg ($60 billion) but some way behind Jeff Bezos of Amazon ($135 billion). Since founding Microsoft, Gates has become a leading player in a new wave of philanthropy. Through the Bill and Melinda Gates Foundation, he has invested heavily in research into malaria and Alzheimer’s and given billions of dollars to fund health and education initiatives.