A front wheel drive car has the engine mounted transversely, with a transaxle driving the two output shafts. Rear wheel drive, the engine is mounted on a transmission (usually) and the driveshaft delivers the power to the rear differential which powers the rear axle, and wheels. Four wheel drive is similar to the rear wheel drive, but at the rear of the transmission is a transfer case. It takes the one output shaft of the transmission, and makes one output shaft to the rear and one to the front...then driveshaft to the front differential and axle, one to the rear.
this is written by a 14 year old... me. so it might be wrong.the cylinders spin the drive shaft which is connected to the differential which is geared is such a way that spins a shaft with wheels attached at either, this shaft has to be spun perpendicular to the drive shaft, otherwise you do what i did when i built my rocket powered go kart and end up in hospital for 2 weeks ...
Check drive train.
An engine is connected to the transmission via the flywheel. At the rear of the transmission is an output shaft. The drive shaft slides on to it, and connects to the rear end, which has gears in it to transfer power through axles to the wheels. (rear wheel drive only)