Easy, Illustrated Instructions on How to Change Brake Pads

Here is a drawing of the brake disk. The wheel, which consists of a rim and a tire, bolts directly to this structure.
Brake pads sit on both sides of the disk, ready to grab onto it when someone pushes on the brake.
Here is a side view. The brake pads are usually designed to only grab in one spot on the disk. On the Hyundai, the brake pads are positioned toward the front-most spot on the disk.
A circular piston is positioned to push on one side of the brake pads.
That piston push is remarkably powerful, so it must be strategically arranged to put steady, even pressure onto the disk. To keep everything lined up and squeezing straight and even, the brake pads and piston are held in place by a chunky iron caliper, seen here colored orange.
The caliper holds the brake piston (cylinder) and the pads together. It also distributes the push of the cylinder to both sides of the brake pads.
When you aren't braking, the pads sit inside this contraption, almost touching the disk as the wheel turns.
The caliper and disk.
The disk in the center is not solid. It has little square holes in it to keep it lightweight and easier to keep cool. The curved gray hose, at the upper left quadrant of this photograph, connects this brake to the master brake cylinder in the car. The hose is full of brake fluid, and that fluid pushes this brake closed. I found it interesting that there aren't any electrical wires needed for the operation of the brakes down at the wheel.
Please continue reading page 3 of Easy, Illustrated Instructions on How to change brake pads.