The camshaft is driven by the crankshaft over timing gears cams are made as indispensable parts of the camshaft and are designed in such an approach to open the valves at the right timing and to keep them open for the important span. An example is the camshaft of the vehicles, which takes the revolving movement of the engine and translates it in to the responding movement important to work the suction and exhaust valves of the cylinders.