Active safety refers to everything designed to help prevent an accident from happening. It can include features such as power-assisted steering systems that give the driver accurate feedback from the road; good suspension characteristics, well-tuned suspension systems, optimum traction and good overall handling characteristics; effective brakes and engines with plenty of power reserve. Seats that reduce fatigue, clear visibility, good climate control, understandable and uncomplicated instruments and controls help the driver to remain alert. Electronic vehicle systems such as the Anti-lock Brake System (ABS), the Traction Control (ASR), the Electronic Brake-force Distribution (EBD), the Electronic Differential Lock (EDL), the Electronic Stabilization Program (ESP®), the roof rack detection system, Audi side assist, and even the voice control system are also active safety features. Together with the car’s passive safety features, active safety systems help to provide optimum protection for all of the car’s occupants.