What is Quattro and why is it important in Audi vehicles?

I've heard about Quattro being a major selling point for Audi cars, but I'm not sure what it actually does. Can anyone explain the technology and its benefits?

Quattro is Audi's signature all-wheel drive system that has been an integral part of the brand's success for decades. It uses a center differential to distribute power to all four wheels, providing improved handling, traction, and stability in all types of driving conditions.