The world's second-richest man is now 64 years old.
Bill Gates has a net worth of $108 billion, according to the Bloomberg Billionaires Index, and he knows how to make the most of it. While he has some indulgences — like a Washington estate worth $125 million, a private airplane, and a luxury-car collection — they make up only a fraction of his massive fortune.
In fact, Gates and his wife, Melinda, previously said it's unfair they're so rich. Instead of spending billions on themselves, they often donate it to charity through the Bill and Melinda Gates Foundation. They've also pledged to give away most of their fortune through the Giving Pledge, which they launched in 2010.
Keep reading for a look at how Gates spends his billions.