This is not a full blog post. I just liked the differentiation between the terms "gaming" and "simulation" presented in "Applied Mathematical Programming" by Bradley, Hax, and Magnanti (Addison-Wesley, 1977).
[In] gaming [,...] a model is constructed that is an abstract and simplified representation of the real environment. This model provides a responsive mechanism to evaluate the effectiveness of proposed alternatives, which the decision-maker must supply in an organized and sequential fashion. The model is simply a device that allows the decision-maker to test the performance of the various alternatives that seem worthwhile to pursue.
Simulation models are similar to gaming models except that all human decision-makers are removed from the modeling process. The model provides the means to evaluate the performance of a number of alternatives, supplied externally to the model by the decision-maker, without allowing for human interactions at intermediate stages of the model computation.