What is the difference between OHV, OHC, SOHC and DOHC engines?

The main difference between these engine types lies in their valve train configuration. OHV (Overhead Valve) engines have the valves located in the cylinder head, but the camshaft is located in the engine block. The camshaft operates the valves through lifters, pushrods, and rocker arms. OHC (Overhead Camshaft) engines have the camshaft located in the cylinder head, directly operating the valves. SOHC (Single Overhead Camshaft) engines have one camshaft per bank of cylinders, operating all the valves in that bank. DOHC (Dual Overhead Camshaft) engines have two camshafts per bank of cylinders, one for the intake valves and one for the exhaust valves.