Millionaires are so 1999.

Billionaires have changed the way our world works. They’ve altered the way we communicate, travel, and live. And along the way, they have made incredible amounts of money for their efforts.

Learning from the 10 billionaires below is not only a good idea if you want to boost your bank account, but also if you want your work to make a difference.

With that in mind, here are 10 lessons from billionaires on earning money, succeeding in business, and finding happiness in life.

1. “You become what you believe. You are where you are today in your life based on everything you have believed.” —Oprah Winfrey, net worth of $2.7 billion

First and foremost, you have to believe that greatness is possible. Many of the world’s billionaires have shifted the way our world works, because they believed that they were capable of doing something that was previously impossible.

Change is possible. Greatness is possible. But you can’t do anything unless you first believe in yourself.

2. “What we say here every day is that our success is really based on our members’ success, our community’s success.” —Pierre Omidyar, net worth of $6.7 billion

Your success is directly tied to how much you do for others. It’s not what you know. It’s not who you know. It’s what you do for who you know. Success follows generosity.

3. “The typical human life seems to be quite unplanned, undirected, unlived, and unsavored. Only those who consciously think about the adventure of living as a matter of making choices among options, which they have found for themselves, ever est