Model checking is a formal method used in computer science to verify the correctness of systems and protocols. It operates by creating a finite representation of the state space of the model, which is analyzed against specified properties, such as safety and liveness. It can be employed in various fields including hardware design, software engineering, and network protocols to ensure that implementations conform to their specifications. The process typically includes generating a state-transition graph, checking properties, and examining all possible states, making it a powerful tool for identifying errors in complex systems before deployment.