Drum brakes are found on older or less powerful cars.
Here is a typical drum brake arrangement seen when the rear wheel has been removed ;
Here are some examples of what the inside might look like once the outer brake drum has been removed ;
Below is a diagram with the internal parts labelled ;
Drum brakes are less powerful than disc brakes.
Drum brakes are more difficult to service and change the brake pads on in comparison to disc brakes because there are more moving parts.
We recommend that if you are going to work on your own drum brakes, you should get a copy of your vehicles Haynes Manual and read it thoroughly.