Superchargers are devices used in reciprocating (internal combustion) engines to compress air that deliver additional air to an engine. They draw power from the engine. Superchargers are placed behind the air intake so they will compress the air before it flows to the cylinders in the engine where it is compressed again. Superchargers use a small rotary compressor to give air from the atmosphere higher pressure. They are powered by gears in the engine's crankshaft.

Superchargers are important at high altitudes where air has low density and pressure and where engine performance deteriorates. Use of a supercharger provides higher pressure air (air that has been compressed) to go the engine.

A turbocharger, also called a turbosupercharger, is a supercharger that is driven by a turbine that draws power from the engine exhaust rather than from the engine. Using a turbine to power the supercharger is more efficient since exhaust gas pressure is used, which is wasted energy. This enables the engine to use all of the power for rotating the propeller. Turbochargers can provide more "supercharging" than the gear-driven type of supercharger.