Photograph:Charles Darrow Playing Monopoly

Monopoly, the most popular board game in history, began life as The Landlord's Game in 1904. Elizabeth Magie devised the game to point out the social pitfalls of unequal wealth among people. But instead, players greedily collected huge piles of money and property, delighting in opponents' financial troubles. Circulated informally at first, the game only gained popularity when Pennsylvanian Charles Darrow produced the first commercial version in 1934. By that time, several changes had worked their way into Magie's educational tool. Players could raise rents by "building" houses and hotels, and creating a "monopoly" of properties allowed incredibly steep rents. Squash the competition and drive up profits-not bad, eh? Darrow produced 5,000 copies at his own expense and sold them through a Philadelphia department store. Hearing of his success, Parker Brothers bought the rights in 1935 and sales soared. At the height of the Great Depression, Monopoly was the best selling game in the country. Since then, Monopoly has appeared in 40 countries and 25 foreign languages. The original game used property names familiar to residents of Atlantic City, New Jersey. But after 1994, Parker Brothers began producing versions representing major cities throughout the country.