Simulator

A simulator is a device or software that imitates the essential features and dynamics of a real-world system or process to support training, analysis, and decision making. Simulators aim to reproduce the behavior, environment, and constraints of the target domain while allowing controlled variation of conditions and repeatable scenarios. They typically rely on models that encode the system's rules, data inputs, and an interface through which users interact.

Simulations can be continuous, discrete-event, or hybrid, and may run in real time or accelerated time. They can be implemented on general-purpose computers, specialized hardware, or immersive environments such as virtual reality. Common modeling approaches include physics-based equations, statistical models, agent-based simulations, and stochastic processes.

Types of simulators include flight simulators for pilot training; driving simulators for vehicle operation; weather and climate models; economic and financial market simulations; power grid and manufacturing process simulators; and medical or surgical simulators used for education and planning. In entertainment, computer games also function as simulators, though with different objectives.

Applications span training, performance evaluation, design testing, risk assessment, and policy analysis. Simulators enable experimentation without endangering people, property, or environments and help validate system behavior before deployment. Model fidelity, verification, and validation are essential to ensure reliable results.

The concept has roots in military training and mathematical modeling, with advances in computing expanding the scope of simulation from simple analog devices to complex, data-driven models. Modern simulators are integral in aviation, transportation, energy, healthcare, urban planning, and scientific research.