Particle systems are often overlooked by rookie game developers because they are not something that will affect game mechanics, or make the AI smarter. However, a particle system is very important in games because not only does it make a static and boring scene look a lot livelier, but it can also create different moods and affect the player's emotion. Particles can be applied to game environments, props, power-ups, weapons, magic skills, and so on.

To create a particle system, go to Create | Particle System, and it will create an empty object with the particle system attached to it. The particle system in Unity is in the form of a component and it has to be attached onto a game object in order for it to be functional, which means you can add the particle system to any game object, not necessarily an empty object only. Then, you will see something like this:

When a particle system is selected, a small window will appear at the bottom-right corner of your 3D scene....