As a side note, particle systems are very powerful, but it is not trivial to tweak and design them.
The implementation details of a particle system are straightforward, as we have seen. But making a particle system that looks realistic and good is something else entirely.
The key to fine-tuning them is to play with the parameters and see how they look, again, and again, and again until we are happy with the result.
To try and throw some light on the obscure art of tweaking particle systems, we are going to do a few examples. You can play with the particles and parameters on your own to see how much of a difference small changes make.
There are two ways of using particle systems: one-shot and continuous emitter. Let's make ...