Using modeling and simulation techniques in game development can look back on a comparably long history, starting in the early 1970s. In contrast to this long tradition of combining games and simulations, it is usually not made explicit which kind of simulation is used, which models are fundament of the simulation, and which role the simulation and the models have in the game based scenario (e.g. non-player characters, environment, engines). This has led to a situation where research in modeling and simulation and development of games run in parallel – it is not clear how recent research results influence the interwoven development of both fields. This paper will start with an attempt to structure both fields, and to provide for a collection of defined terms, which help to relate modeling and simulation approaches to game development.