Why does the Audi A6 have a Quattro all-wheel drive system?

I've been looking at Audi A6s and noticed that many of them have the Quattro all-wheel drive system. What does this system do and how does it benefit the car?

The Quattro all-wheel drive system in the Audi A6 provides power to all four wheels, allowing for better traction and control on various road conditions.

This system also helps with cornering stability and increases overall performance, making the Audi A6 a great option for drivers who want both power and control.