How does a Microwave Oven work?
The simple answer is friction.
The longer version is that it vibrates the water molecules in the food at 2.45 Giga Hertz. The microwave oven works on magnetism, water molecules have a North and South pole and every second the magnetron inside the Microwave oven turns the molecule 4900 million times.
Wow, that is fast.
Now I don’t know about you but I reckon I would get more than a little hot under the collar if I was turning that fast. The heart of the system is a high voltage circuit that is a tuned radio transmitter. The antanna is the magnetron, the magnetron contains two powerful magnets and could be compared to the old fashion valves.