Brakes help you slow down your car and bring it safely to a stop. When you hit the brakes, you bring your car to a slower speed.
Don't confuse brakes with breaks, which are periods of time in which activity stops, like coffee breaks or winter break. Both of these sound-alike words can also be verbs: you brake when your foot presses down on the pedal that makes a vehicle slow down. When you break for dinner, you stop working in order to eat, but if you break something, like a window, you cause damage — the thing you break no longer works.