How does the all-wheel steering system work in the Audi A8?

I've heard that the Audi A8 has an all-wheel steering system, but I'm not sure how it actually works. Can someone explain?

The all-wheel steering in the Audi A8 works by adjusting the rear wheels to turn slightly in the opposite direction of the front wheels at lower speeds, which improves maneuverability and reduces the turning radius. At higher speeds, the rear wheels turn in the same direction as the front wheels, which improves stability and handling.