The simulation software function models real or imaginary systems that shows how these systems or similar ones work and demonstrate their concepts. There are two types of simulations that teach about something: physical simulations and iterative simulations. Physical simulations let users manipulate things and processes that are represented on the screen. Iterative simulations "speed up or slow down processes" either extremely slow or fast in which "the students can't see the event unfold." There are also two types of simulations that teach how to do something: procedural simulations and situational simulations. Procedural simulations teach the correct sequences of steps for certain prodecures while situational simulations have students react to various "hypothetical problem situation." An example of a simulation software is the game The Sims. This life simulation game requires players to create a family to tend to from birth to end.