Before the introduction of the euro, francs were also used in France, Belgium and Luxembourg, while Andorra and Monaco accepted the French franc as legal tender (Monegasque franc).
Inside the caliper is a brake pad, a small block of friction material backed with a metal plate. When you step on your brake pedal, pistons inside the caliper cause it to apply pressure to the brake pad which squeezes the rotor, causing the car to slow or stop.
The 'car' electric circuits do everything but run the engine, so they include things like wipers, heater fan, head lights, tail lights, stop lights, indicators, hazard system, reverse lights, cigarette lighter, stereo, alarm, demister etc etc.