In his book Half Real: Video Games between Real Rules and Fictional Worlds, game studies theorist Jesper Juul sets out five main types of game worlds (131-132):
1. Abstract Games: games that do not represent something else, either in its pieces or in its entirety. These types of games are centered around the rules, with little to no fiction to dress them up. Examples: Backgammon, Tetris, Tic-Tac-Toe.
2. Iconic Games: games with individual components that have iconic meaning, but have no fiction as a whole. In cards, for example, royalty cards exist and seem to represent high values, but no fiction arises from this comparison. Examples: Cards, Checkers.
3. Incoherent World Games: games which express a fiction, but are impossible to explain without referring to the rules. Donkey Kong, for example, tells the story of a man trying to rescue his girlfriend from the hands of an ape that kidnaps her, but the fact he has three lives is not part of the fiction. Examples: Donkey Kong, Chess
4. Coherent World Games: games in which the rules are integrated within the fiction, and most (if not all) of the game can be explained without referring to the rules of the game. Examples: most adventure games, like Tales of Monkey Island.
5. Staged Games: games in which abstract or representational games are played in a more elaborate fictive world; a "game within a game." Examples: Wario Ware Inc., Puzzle Bobble.
