How microwaves are structured

In a microwave there are a lot of different components that make it work, one component that makes microwaves unique the magnetron which was how microwaves were first invented, and the magnetron produces the electromagnetic waves so that they are able to cook food. The waves are used to control where the electromagnetic waves go inside the cooking chamber. Once the power is turned on "A capacitor is used to smooth out the current before it reaches the magnetron. (1)"

Electromagnetic waves are created by both electric waves which are created by having the microwave plugged into your normal power socket and magnetic waves which are created by the magnetron tube. The magnetron tube uses the space between an anode and the cathode (filament-heat filament) as a grid to create magnetic energy, this space is referred to as the anode cylinder. The anode cylinder also referred to as the resonant cavity control the frequency output of the tube. Powerful magnets are positioned around the magnetron so that the magnetic field runs parallel with the filament. The antenna transfers the electromagnetic energy (RF energy) to the wave guide.

http://repairfaq.ece.drexel.edu/sam/maganode.gif

Magnetron from the top (3) Magnetron lengthwise (4) Magnetron Sideview (5)