How does the Audi A4's quattro work?

I've heard the Audi A4 has a quattro all-wheel drive system, but I don't understand how it differs from other AWD systems. Can someone explain?

The Audi A4's quattro all-wheel drive system uses a center differential to evenly distribute power between the front and rear axles, providing better traction and handling in all weather conditions.

Compared to other AWD systems, the quattro in the Audi A4 also has the ability to send power to individual wheels, further improving traction and stability.

I've driven the Audi A4 through snow, mud, and rain and the quattro system never fails to impress. It makes a huge difference in overall performance and control.