How does a car heater work?

[first time answering questions] car heater works like the reverse of the normal cooling radiator - in fact the heater is like a small version of the rad that's on the frnt of the car - the hot water from the engine block goes into this small rad and the heater fan blows air thru it into the car - the hot heater rad loses heat into the car and - bingo - you get warm inside