What is billboarding, and can or should it be used to create special effects for 3D games on weapon blasting effects?
What is billboarding ?
Billboard is a textured flat object, usually a polygon, which faces the camera. Its direction usually changes constantly as the object and camera move, so it always faces the camera direction, this operation is called Billboarding. Billboards usually use texturing + alpha to represent many phenomena that do not have smooth solid surfaces (e.g. Clouds, Grass, Smoke, Fire).
Can or should it be used to create special effects for weapon blasting effects?
You need to make a distinction between billboards and particle systems. A particle system is a set of small objects that are animated and controlled using an algorithm. Particles can be represented by Billboards, but other forms are also common such as points and lines. You can make gun blasting effects using billboards, but in the end, you will need a way to control those billboards which will end you up making a particle system (though might be a very simple one)
A billboard within your game is always orientated to face the camera. As the camera moves the object is orientated to face the camera. The same theory can also be applied to cause an object to always face another object within your game.
based on orientation its divided into 2 types Points, Axial