This video celebrating 25 years of the quattro system shows exactly how it has revolutionised motorsport.
The quattro system was first introduced in 1980 on the Audi Quattro and has since been deployed to most of the Audi range.
In the original quattro system, the engine and transmission are situated in a longitudinal position. Power is sent through the transmission to a mechanical centre differential which splits it between the front and rear axles.
The quattro system is probably best known for changing the face of rallying after Audi mated a high power turbo engine to an all wheel drive layout.