What was the board game that became Monopoly first meant to teach?

In 1904, an inventor named Lizzie Magie patented, or got the legal rights to, The Landlord's Game, about buying land and charging rent. It was a warning: she wanted players to feel how rent let one owner drain everyone else's money.

People made their own homemade versions. In 1935, a salesman named Charles Darrow sold one, called Monopoly, to the game company Parker Brothers and got rich. The company bought Magie's patent for $500.