Using the satellite navigation data, the optional Adaptive cruise control knows exactly where the car is, so if travelling on a motorway and the car in front brakes and indicates left (because the driver wants to take the next exit) the system can recognise this - thanks to the camera image and because it sees the exit on the navigation data. In this scenario a traditional radar based cruise control system would brake, whereas the A8 would continue uninterrupted.
Article source: www.audi.co.uk