The difference between “active safety” and “passive safety” in the field of automobiles can be explained quickly and simply:
Active safety is: not to hit the tree. Passive security is: If you have hit the tree after all, do not get hurt!
Active safety has played no role in vehicle construction for many years. In the beginning it was all about passive safety: the passenger compartment with defined crumple zones was invented, the seatbelt became normal and later the airbags were added. Passive safety was always what you would rather not try.
The better the passive safety became, the more the thought of “active safety” penetrated into the consciousness - first among the designers, later also among the car buyers and drivers.
Active safety begins where accidents are avoided. So do not get off the road and do not hit the tree. This can be very subtle things: good low beam, for example, or even the right tires. Only later were added ABS and ESP to the basic equipment. Today there are no more cars without these electronic helpers.
While progress in passive safety is always a little under the radar of customers, active safety systems are aggressively promoted by manufacturers. From Lane Keeping Assist, to Emergency Brake Assist, from Blind Spot Alert to Night Vision Assist. The list of “active safety features” is getting longer and in the end there is “autonomous driving”. Apparently a horror for many active drivers, but I am convinced that autonomous driving will turn out to be the highest level of active safety in automobiles. Sensors don't get tired. Sensors are not careless and sensors do not need passive safety for emergencies.