What is Quattro all-wheel drive and what makes it unique in the Audi A4?

I am interested in purchasing an Audi A4 and have heard about their Quattro all-wheel drive system. Can you provide more information on how it works and what makes it stand out from other all-wheel drive systems used in cars?

Quattro all-wheel drive is a signature feature of Audi vehicles and sets them apart from other all-wheel drive systems. It uses a center differential to distribute power between the front and rear axles, allowing for better grip and traction on all types of terrain.