At minimum, a maritime simulator consists of a software that realistically simulates the dynamic behavior of a vessel and its systems in a simulated maritime environment and an interface that allows the person using the simulator to control the vessel and interact with its simulated surroundings.
A maritime simulator needs software that simulates a vessel's dynamic behavior and its systems in a simulated maritime environment, along with an interface allowing the user to control the vessel and interact with its simulated surroundings.