What is a magnetron?

The magnetron converts high voltage electricity into the microwave energy that heats food. Its failure is confusing to owners because everything else keeps working, the light comes on, the turntable spins, the timer counts down, and the food stays cold. Magnetrons are killed early by running the oven empty and by sustained arcing from a damaged waveguide cover. Replacing one is professional work because of the capacitor sitting next to it.