Quattro is symetrical AWD. It's Audi's name for it. Just like Honda's new SH AWD or VW's 4motion. All Wheel Drive systems basically all function the same. They have the ability to transfer torque to the front or rear wheels, or in newer versions (Subaru, Honda, Audi) they can actually transfer torque to specific wheels rather than a front/rear split or left/right split.