Simulation refers to creating a computer model or program that imitates or emulates the behavior of a real-world system or process with something virtual, like a digital twin. Simulation is most frequently used to study the behavior of complex systems that are difficult or impossible to observe directly. For example, agent-based modeling (ABM) and multi-agent AI, ABM’s subset, can be used within a simulation to study agent interactions within a more extensive simulated system or environment.