what is rear wheel drive

Rear-wheel drive (RWD) is a powertrain distribution system used in motor vehicles, in which the engine drives the rear wheels only. Until the late 20th century, RWD was the most common configuration for cars. Most RWD vehicles feature a longitudinally-mounted engine at the front of the car. The most common layout for an RWD car is with the engine and transmission at the front of the car, mounted longitudinally. Other layouts of RWD cars include front-mid engine, rear-mid engine, and rear-engine. RWD cars bring advantages and disadvantages. Some of the advantages include better balance for drivers because of its even weight distribution, and better at putting their power down on the road when conditions are dry, as the mass of the car shifts rearward under acceleration, transferring weight to the rear wheels, helping them stick to the road. Some of the disadvantages include less grip in slippery conditions, as there is no engine sitting above them to help push the tires down onto the road.