The co-creator of Dungeons and Dragons, the world's most popular role-playing game, has died at his home in Wisconsin.

Gary Gygax was legendary among the gaming community for his invention, and its more popular successor Advanced Dungeons and Dragons.

The two games are still the most popular role-playing games and are a multi-billion dollar industry.

Games in which participants create characters from magical or mythical scenarios have been around for decades.

But Gygax and his friend Don Kaye began publishing scenarios in 1974 for others to play, and codified a set of rules so that players could write their own games.

"The essence of a role-playing game is that it is a group, cooperative experience," Gygax said in an interview with The New York Times in 2006.

"There is no winning or losing, but rather the value is in the experience of imagining yourself as a character in whatever genre you're involved in, whether it's a fantasy game, the Wild West, secret agents or whatever else."

Most role-playing games are now played entirely on computer, of which Gygax largely disapproved.

He felt that computer graphics replaces one of the most important facets of the game, i.e. imagination.