The spark is generated by the discharge phenomenon between the electrodes, and the gasoline engine generates power by timely combustion of the fuel and the mixed gas, but the gasoline as the fuel is difficult to self-ignite even in a high temperature environment, and it is necessary to make it timely burn. "Fire" to ignite. The spark ignition mentioned here is the role of "spark plug". The overall performance of the engine depends entirely on whether the spark plug flashes or not. We tend to compare the engine to the "heart of the car," but we can better compare the spark plug to the "heart of the engine."