What's Cylinder Head in an Engine?

The cylinder head is the metal casing which covers the engine. It seals the main cylinders of the engine and prevents oil and other substances from finding their way inside. It also contains a number of valves vital to the engine. Internally the cylinder head has passages called ports for the fuel / air mixture to travel to the inlet valves from the intake manifold, for exhaust gases to travel from the exhaust valves to the exhaust manifold and for antifreeze to cool the head and engine.

1. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by ahead gasket. In most engines, the head also provides space for the passages that feed air and fuel to the cylinder, and that allow the exhaust to escape.
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In an internal combustion engine, the cylinder head (often informally abbreviated to just head) sits above the cylinders on top of the cylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket. In most engines, the head also provides space for the passages that feed air and fuel to the cylinder, and that allow the exhaust to escape. The head can also be a place to mount the valves, spark plugs, and fuel injectors.

The Cylinder head is the metal case ,which covers the engine .It contains guide ways for oil and valve inside the engine.It covers the top portion  of the Cylinder

 

http://en.wikipedia.org/wiki/Cylinder_head

In an internal combustion engine, the cylinder head (often informally abbreviated to just head) sits above the cylinders on top of thecylinder block. It closes in the top of the cylinder, forming the combustion chamber. This joint is sealed by a head gasket. 

Cylinder Head in the Engine is the one of the component of the Engine which is mounted top of the Engine that's over the cylinder of the Engine. In the Cylinder head the both inlet and exhaust valves are mounted. and in the over head cam engine the cam also placed in the Cylinder Head.

I agree with the expert answers.

There are2 types of Engines. One is External and another is Internal based upon the combustion. Locomotive engines are External and others such as vehicle engines are Internal.

All Internal Combustion Engines has2 parts. One is the Block accommodating Cylinders carrying Pistons and the other is Head accommodating Valves. These Heads are on the top of the Cylinders of the blocks called Cylinder Heads.