Zuma is an arcade game where you have to shoot balls or colored balls to gather them in groups of three at least in order to remove them. All balls follow a path and they progress towards the bottom of the screen.
You must ensure to remove them all before they reach the bottom. That is why you will have to focus and concentrate in Zuma games.
Zuma games reflect the same principle of the original Zuma game, with variants more or less easy and friendly. You will for example have bombs to launch the balls or bonus marbles that stop time or make more balls disappear.