An ignition switch is a crucial component in a vehicle's electrical system. It is responsible for starting the engine and powering various electrical systems when the key is turned or the start button is pressed. The ignition switch connects the battery to the ignition system, allowing the engine to start and run. In addition to starting the engine, the ignition switch also controls other functions, such as the dashboard lights and accessories like the radio. If the ignition switch fails, it can prevent the vehicle from starting or cause electrical issues, making it an important part of the automotive system.