- Paintball guns are also known as markers. The term "markers" is used so that people won't assume the sport is violent. The first paintball markers were actually used to mark cattle. The marker uses compressed air, nitrogen or carbon dioxide to expel a plastic ball of paint.
- The most basic form is the pump-action marker. The player cocks the gun, just like a traditional shotgun. The semiautomatic does not need to be cocked but only fires one paintball every time the trigger is pulled. The automatic paintball marker can shoot paint balls as long as the trigger is depressed. Numerous companies make paintball markers, but all use the physics of pneumatics to construct them.
- The trigger frame, bolt and valve are the main components of the firing mechanism. These are usually built in an aluminum body to reduce weight and cost. The other parts of the marker are the barrel and the hopper/loader. These parts can usually be changed at the consumer's will.
- Workers at paintball factories make the the trigger frame form plastic or aluminum. The trigger is put in place to use a series of springs and levers that thrust the hammer forward. The trigger usually has a barrier around it so that only a player's finger can fit between it and the trigger itself. It is a safety precaution.
- The valve and bolt assembly is the core of the paintball marker. The bolt controls the direction of air from the tank, while the valve controls whether the marker is actually firing. These two components are so closely connected that a lot of markers are built with a combination of the component. The valve can be built into the bolt.
- The body of the marker must be able to hold all the components. It's built with a handle a chamber where the bolt and valve assembly can go, as well a place for the barrel, hopper/loader and air tank to be installed.
- A single company builds the body with the components in it. It also comes with the factory barrel and hopper/loader. Different companies make air tanks, loaders, and barrels to satisfy consumer needs.
