Getting started in paintball is not difficult. You only need some basic paintball equipment and you will be ready to play. It doesn't have to be expensive, you can spend as little or as much money as you want.
Gun or marker
Paintball guns (also referred to as markers) are the very basis for the sport of paintball. They come in all shapes and sizes, but to play you only need something that propels paintball fun in a somewhat straight line. Paintball guns can be bought new for less than $40 or rented for $10-$20 a day from many paintball shops.
Paintball masks exist for the simple reason of protecting your face. A flying paintball can leave a small bruise if it hits your body, but a direct shot in the eye can blind you. Make sure your mask is approved for paintball and then use it as if your eyesight depended on it.
Paintballs need to get into the chamber of your gun before you can shoot them and the best way to do this is with a hopper. A hopper is a small container that sits on your gun and feeds paint into your gun.
The propellant to fire a paintball fun comes from compressed gas - usually either compressed air or compressed carbon dioxide (co2). Guns require one of two kinds of compressed air tanks: small 12 gram tanks that also are used in bb guns or larger tanks that screw onto the gun. A larger tank of co2 or compressed air will be able to shoot hundreds of paintballs.
Along with paintball guns, paintballs are what make paintball possible. These spherical containers of paint are loaded into your gun and then shot by the expansion of compressed gas. Many different brands and colors exist, and more expensive usually means a better ball. For a beginner, though, they all perform about the same as long as they are not too old, so pick what looks good to you and use it. Be sure to bring enough to last as long as you want to play.