Some, like Melinda Gates and Priscilla Chan, became affluent through marriage. Others, like Oprah Winfrey, earned fortunes on their own.
Australia is about to witness the largest intergenerational wealth transfer in our history, but giving through bequests in wills is currently low.
The US$2 billion that the Amazon founder and his wife are donating to help the homeless and educate young kids may appear selfless. But this money may also soften calls to raise taxes on the rich.
Amazon's founder turned to Twitter to crowdsource ideas for his charitable giving. This populist approach and his preference for short-term results set Jeff Bezos apart from other mega-donors.