I know that both indicate people with wealth, but what's the main difference between "millionaire" and "billionaire"?
Native speaker’s answer
Rebecca
A "billionaire" is someone richer than a "millionaire." A "billionaire" is a person with a net worth or wealth of over a billion dollars. A billion has nine zeros behind it: 1,000,000,000. A "millionaire" is a person with a net worth or wealth of over a million dollars. A million has six zeros behind it: 1,000,000. "Billionaires" and "millionaires" have way more money than the average person does, but a billionaire is richer. Ex: Bill Gates and Elon Musk are both billionaires. Ex: He became a millionaire after winning the lottery.