How does the Audi 80's Quattro system improve handling and performance?

I've heard that the Quattro system is a major selling point of the Audi 80, but I'm not sure exactly how it works. Can someone explain it to me in more detail?

The Quattro system is a permanently engaged four-wheel drive system that distributes power to all four wheels, providing improved handling and traction in all conditions.

The Quattro system uses a center differential to distribute power between the front and rear axles, giving the Audi 80 exceptional balance and stability while driving.