A cylinder head is a casting generally made out of iron or aluminium that holds the valves, valve springs and retainers and one or two camshafts (overhead cam engines only). The cylinder head has numerous machined surfaces to provide a precision fit to mating parts. Inline four- and six-cylinder engines have one cylinder head. V6, V8 and V10 engines have two cylinder heads.
The cylinder head, when used with a head gasket, seals the cylinders so that they're capable of building compression for engine operation.
The engine in your car will last for many thousands of kilometres if driven and cared for properly. The best way to care for the cylinder head is to follow a good maintenance regimen. This includes regular oil and filter changes, engine performance check-ups, and cooling system maintenance. The main enemy of the cylinder head is overheating. If you notice that the engine temperature is higher than normal, take your car to a good repair shop as soon as possible. Overheating can quickly warp aluminium cylinder heads and contribute to head gasket failure. Any time you notice engine performance dropping off, or observe problems with coolant temperature or oil pressure, it's wise to have these looked into as soon as possible by a qualified professional.