Super charger  and turbo charger  a-car homepage

updated :

The intake of an engine has a friction. This makes that the volume of air taken in to the engines, for each turn, gets lower when the speed of the engine increases. So does the energy delivered bij each turn.

The solution is to pump more air in to the engine when the engine speed is higher.

This compressor is called "super charger"

The energy for the super charger can be supplied by an electric engine, belt or gear driven, or by a turbine mounted in the exhaust. When the energy comes from a turbine in the exhaust we call it a turbo charger. Comming from an electric engine we call it an electric super charger.