The water pump is usually in front of the cylinder block, belt-driven from a pulley, on the front of the crankshaft. A hose connects it to the bottom of the radiator where the cooler liquid emerges.
It has fan-like blades on a rotor or impeller. Coolant enters the center of the pump. The rotor spins, and centrifugal force moves the liquid outward. It is driven through the outlet into the cooling passages called waterjackets.
Waterjackets are passages in the engine block and cylinder head that surround the cylinders, valves and ports.
Coolant can be also directed to hot spots such as the exhaust ports in the cylinder head, to stop local overheating.