How the car brakes work?

In its most basic form, automotive brake systems consist of a brake pedal that is connected to a closed
loop of brake lines filled with fluid, as well as calipers, pads and rotors.
The brake rotors rotate along with the wheels and tires as the vehicle moves, but the calipers at each
wheel are stationary. Master cylinders and brake boosters are usually involved, but essentially pressing the brake pedal forces brake fluid through the brake
lines or hoses.
When that pressurized fluid enters a brake caliper, it pushes pistons out of the caliper, which in turn force the brake pads against the brake rotor. The friction created when the pad rubs against the rotor slows the vehicle, wears down the pads and rotors a bit, and creates a lot of heat. This conversion of kinetic energy (the energy in the moving vehicle) into
thermal energy (the heat generated under braking) is the actual work being done by the brake system.
Because of the tremendous amount of heat being
generated in a stop, brake components are designed
to absorb that heat and dissipate it out into the
atmosphere as quickly and efficiently as possible.
Because cooler components have a higher thermal
capacity than hot ones, shedding that heat between
stops is important for optimal stopping power the
next time you need it.

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