The document discusses various active safety systems used in modern vehicles, including anti-lock braking systems (ABS), traction control systems (TCS), electronic stability programs (ESP), and descent control systems (DCS). It describes how these systems utilize sensors and electronic control modules to monitor vehicle dynamics and apply brakes independently to wheels to maintain stability and prevent skidding, especially in emergency braking situations, low traction conditions, and steep downhill driving. The presentation emphasizes that these systems provide improved vehicle control and safety and are now standard features on most new vehicles.