Approximately 1 billion people, in 111 countries and 43 languages, have played Monopoly since Parker Brothers published it in 1935.  The traditional story goes that Charles Darrow, an unemployed radiator repairman, invented the game and populated it with property names from Atlantic City where he had summered as a child.

There is, however, an earlier chapter in the story that most people don't know about.  Namely that Monopoly was actually based on "The Landlord's Game" released in 1906 by an actress from Maryland named Lizzie Magie.  

The October issue of Harper's has a great feature article on the true, and somewhat surprising, origins of the Monopoly.