Topology

In mathematics, topology is the study of shapes and spaces. In his book, A Theory of Fun for Game Design, Raph Koster uses the term to describe the general shape of a game experience, the elements that do not seem to change from game to game in a certain genre.

As an example, he states two common paradigms of early platformers (Koster 70): These topologies continue to pop up in games, usually through the imposition of a time attack or secret areas system.
 * "Get to the Other Side" games -- Frogger, Donkey Kong, and Kangaroo.
 * "Visit Every Location" games -- Pac-Man, Dig-Dug, Q*Bert

Game topologies may also be considered units under Ian Bogost's unit operational theory of game criticism.