The internal combustion engine is an engine in which the combustion of a fuel occurs with a mixture of air in a combustion chamber.
In an internal combustion engine, the expansion of the high-temperature and gases produced by combustion applies direct force to the pistons.
This force moves the pistons over a distance, generating mechanical energy, which is in turn transmitted to the flywheel via the crankshaft.
The term internal combustion engine usually refers to an engine in which combustion is intermittent, such as the more familiar four-stroke and two-stroke engines.
With variants, such as the six-stroke piston engine and the rotary engine.