An engine or motor, is a machine designed to convert one form of energy into mechanical energy

Types of Engine:
1. External combustion (E.C.) Engine
2. Internal Combustion (I.C.) Engine

Types of I.C. Engine
According to number of stroke:
1. Two stroke engine
2. Four stroke engine

According to design of engine:

1. Reciprocating engine (piston engine)
2. Rotary engine (Wankel engine)

According to fuel used:
1. Diesel engine
2. Petrol engine
3. Gas engine
4. Electric engine

According to method of ignition:
1. Compression ignition engine
2. Spark ignition engine

According to number of cylinder:
1. Single cylinder engine
2. Multi-cylinder engine

According to arrangement of cylinder:
1. In-line engine
2. V-type engine
3. Opposed cylinder engine
4. W-type engine
5. Opposite piston engine
6. Radial engine

According to air intake process:
1. Naturally aspirated
2. Supercharged engine
3. Turbocharged engine