A billionaire is a person who has a net worth at or exceeding one billion dollars. Generally this term is measured in U.S. dollars.
The world's first billionaire was oil tycoon John D. Rockefeller, who passed the milestone in 1916. Other moneyed barons soon emerged, including Henry Ford, Lamar Hunt, and J.P. Morgan.
Since Rockefeller's induction, the process of becoming a billionaire has become slightly less fantastic, due to inflation. There are numerous billionaires in the world today, including celebrities such as Paul McCartney, J.K. Rowling, and Oprah Winfrey. Today, the main fields to find billionaires are:
Although billionaires come from all walks of life, including oil, chewing gum, packaging materials, real estate, television and film, and cosmetics.
Much like billionaire was at the turn of the 20th century, the race is on to find the first trillionaire. It is widely expected that the world's richest man, Bill Gates, will reach a net worth of $1 trillion sometime in the next 20-30 years. Only time will tell if we'll reach such an astronomical number.