If you have ever played 3D games, you must have seen particles in action. Many 3D games use particles to simulate all kinds of (mostly natural) phenomena such as explosions, falling leaves, and blood spatters.
In Papervision3D, a particle can be described as a 2D graphic that can be scaled and positioned relative to a 3D point. Think of it as a lightweight plane that always faces the camera. This chapter mainly discusses the following two aspects of working with particles:
Billboarding, which is a technique used to cut down the number of triangles in your scene
Creating natural phenomena, which is usually done with the help of a particle system
The two aspects do not exclude each other. However, this classification is a good starting point when discussing particles in Papervision3D.