Windshield glass is not the same as standard glass, as it is specially designed for cars. They are made in such a way as to support the structure of a car, with the help of different kinds of safety glass. Safety glass is always used in automobiles due to the fact that there are less chances of injury when it shatter.
The two different kinds used are laminated and tempered glass. The windshield itself is laminated glass. In 1927, the car industry started using laminated glass, which is made by two pieces of glass stuck together, with transparent plastic known as polyvinyl butyral, or PVB. The plastic and glass is infused together using heat and pressure.
This technique prevents a windshield from shattering during collisions. It is designed to absorb the impact without shattering and offer protection to passengers in the vehicle. If they are not wearing their safety belts and are thrown forward into the windshield, the vinyl will act like a cushion. Since this does not normally shatter, the broken pieces will stick to the plastic lining and will have a spiderweb appearance.
Laminated glass is normally used in cars when the possibility of human impact can happen. Sometimes it can be install in side and rear windows too. It can also be installed in store windows in certain locations when hurricanes are a common occurrence.
While the side and rear windows of a car can have laminated glass, they are usually made from tempered glass. Fast heating and cooling processes are used to make tempered glass. If an accident occurs or if the stability of glass is compromised, such as being hit with an projectile, the tempered glass does not shatter. It does, however, break into tons of small pebble shaped pieces. These pieces are not sharp, so they will not cut like normal broken glass.