How does the advanced safety technology in the Audi A6 prevent collisions?

I've heard that the Audi A6 has several advanced safety features, such as adaptive cruise control and lane departure warning. How exactly do these features work and how effective are they in preventing collisions?

The Audi A6 comes equipped with a pre sense front system which uses radar and camera sensors to detect potential collisions and can automatically apply brakes if necessary. Additionally, the car's lane departure warning uses a camera to monitor your position on the road and can alert you if you start drifting out of your lane.