Car’s safety ratings: Until the 1960s, a collision was not a concern in motor vehicle design. The notion was that the biggest and strongest vehicles would come out the best.
This is still true if the vehicle is what you are worried about. However, for the people inside, this is a different story.
If a vehicle is so rigid that it does not bend when it hits something, it does not absorb any of the energy f the impact. The full force of the impact is transmitted to the driver and other occupants.
Bodywork that bends does absorb some of the impact energy and the force inflicted on the occupants is concomitantly less.
For this reason, cars manufactured since the 1960s have been designed with energy-absorbing “crumple zones” fore and aft, with a “rigid cell” in the middle that ensures that the crumpling does not cave in on the occupants.
And because the remaining force of a big crash could still whiplash the driver and the occupants against the inside of the safety cell, seatbelts and head restraints were often used.
This combination of systems hugely improved the chances of survival in even quite severe crashes. In really heavy collisions, occupants could still be hurt because doors flew open or jammed shut. Moreover, the engine, steering wheel, and pedals could be forced into the passengers’ compartment and strike the passengers like sledgehammers.
Today, doors now have anti-burst locking mechanisms; engine mounting shear is a way that sends the large lump of Iron on the floor in a big crash, and the shaft f the steering wheel is designed to bend sideways instead of spearing towards the driver’s chest.
Other developments include airbags and the instant crash-tensioning of seatbelts; crumple zones have become more progressive and effective from different angles. Sidebars have been put in the doors and the integrity of the rigid cell is more exact and roof pillars do not kink.
All these things, individually and collectively are now measured by NCAP ratings, not just for their presence but for the precise degree of effectiveness. Their car safety ratings are on the internet.