When did cars start putting in seat belts?

While rudimentary seat belt designs existed earlier, the widespread adoption of seat belts in cars didn't happen overnight. There's no single year, but here's a timeline:

* Early experiments (1900s): Early versions of seat belts appeared in the early 1900s, but they were not standard or widely used.

* 1949: Nils Bohlin, a Swedish engineer working for Volvo, invented the three-point safety belt design that is now the standard.

* 1959: Volvo started fitting their cars with Bohlin's three-point seat belts.

* 1960s: The adoption of seat belts in cars began to increase in the US and other countries, but it was gradual. Legislation played a key role in accelerating this process.

* 1968: The US government mandated seat belts in all new vehicles.

So, while the *invention* was in 1949, the widespread *inclusion* in cars started in the 1960s, driven largely by legislation and increasing awareness of their life-saving potential. Even after being mandated, it took many more years for seat belt usage to reach high levels.