Hi 
,question here.What’s the difference between particles and add object actuator(oh,and if there is something that good in particles like not taking much fps or something,will blender game engine ever support the Particles thingy)?I really dont know what particles are famous for 
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Particles are used outside of the game engine.
What do you mean?Ive seen so many games , where there are particles used or maybe im wrong.Are particles used only in Render Engine , is that what you mean?
Particles are only for the render engine, unfortunantly. I’ve heard something about them being put in the game engine though.
If you use the “add object” acutator in the game engine, all your particles will be going to same direction unless you use complex python and stuff.
Not to mention the fact that game engine particles are slooooooow! 
Actually particles are little things that can form realistic smoke, mist, atmosphere, fire, water, fur or more dependend on the shader you apply to it and the settings of those particles. It would be cool indeed to have those things added to the game engine, but no idea if that will ever happen. :-?
The difference between the add object actuator and a particle system is quite simple: The add object actuator just adds one object at a time while a particle system adds a lot of objects and gives better access to the added objects for controlling the behaviour (velocity, direction, damping, fading in/out, etc.).
Additionally you can use the add object actuator to create your own particle system in the Blender game engine - but you’ve got to script it by yourself with Python and probably it wouldn’t be as performant as a hardcoded particle system.
KEinStien basically covered it. You can 'fake" particles in the game engine by using and add object actuator with some alpha shading and maybe some tiled/animated textures and a LOT of python. Do not ask me how do to it I am not that good, YET. Subtabi did something like this in a demo months ago. The point is though even though you might get smoke or flame, or haze using these methods in the game engine it will be REALLY SLOW and will not look anywhere near as realistic as the particle system that is used in the rendering portion of blender.
Lol nothing you do in the game engine is as realistic as when you render stuff, because that is raytraced and takes a long time to even make ONE picture of. You can get pretty decent particle effects with add object actuator, even without python. If you use a few empties to add multiple things at once, good ipos for things, and really nice textures, you can make it look really good for whatever you are trying to do. Making it run fast, you just have to balance how good it looks with how fast you want it to run. You have to deal with that juggling act for all game graphics though. But ipos are good enough for most particle systems. Be creative!
True, Saluk. Especially if using only a simple particle system using emtpies, ipos and add object actuator only as addition to other effects - for example fire: a billboard texture with some rendered frames of flames and a few sparks and flame/smoke particles looks much better than a full-blown fire made with a particle system - and in addition: it’s faster! But actually I’d prefer some Python for that because it’s possible to make it look more random…
Thanx for info guys !It would be great to have a particle system supported in the game engine , but i can live without it too 
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