The law in California says that all drivers and passengers must wear a seat belt while the car is in motion. This is a primary law, which means that you can be pulled over and ticketed for not wearing a seat belt, even if you are not breaking any other traffic laws.
There are a few exceptions to this law. If you are a driver or passenger in a taxi, limousine, or other hired car, you do not have to wear a seat belt. And if you are riding in a bus, you are only required to wear a seat belt if the bus has seat belts installed.
Despite the law, many people choose not to wear a seat belt. Some people find them uncomfortable, and others think that they are not necessary if they are only going a short distance. But the fact is that seat belts can save lives, and it is important to always wear one when you are in a car.