I'm not technically minded either, but there are 2 sorts, the stuff you get on the yank tanks - a "roots" type, and the one fitted to the cars here. Both are driven from a belt from the crankshaft - the bit that the pistons drive - they then drive a turbine in the air intake to push more air into the engine. You can then pump in a bit more fuel and get a stronger explosion in the cylinders. Now watch me get shot down!!