Before 1973, if you had said something like "games are a storytelling medium," just about anyone would have looked at you as if you were mad - and anyone knowledgeable about games would have assumed you knew nothing about them.

Before 1973, the world had essentially four game styles: classic board games, classic card games, mass-market commercial board games, and the board wargame. None of these had any noticeable connection to story: There is no story in chess, bridge, Monopoly, or Afrika Korps.

But in the early 1970s, two things happened: Will Crowther's computer game adventure Colossal Cave, and Gary Gygax and Dave Arneson's tabletop role-playing game Dungeons and Dragons.