How the heck
 

In Command and Concuer Renegade a buch of fool with snipers are always doing this lag trick where they strafe to the side then dissapear and then you see them strafing to the side again. Like for example if I were to be hiding behind a mountain then I peer out(move to the side) then I dissapear and reapear behind the mountain, then I peer out again and so on and so forth. I don't know if you'll get my explanation but hopefully someone will. And BTW don't call me a noob!:) Oh and my question is how the heck do those snipers do that....

Never played it, but if it is a bg problem, they will probably fix it with a patch. If not, then hopefully someone will ba able to answer your question.

it might just be lag??

Truth is that game is horribly buggy.. and they proally wont be patching it anytime soon. it sold HORRIBLY! and westwood closed it's doors (at least the vegas office did, and they are the ones who worked on C_C:renegade)

Yeah but it can't be a lag because they can stop doing it whenever they want. In fact only the sniper guys do it.

Ask EA. You can also check http://www.gamefaqs.com/

Your description are unclear to me. Are you saying that they do not have ANY cover to hide behind? That they just become invisible?
Usually a sniper would shoot you from a far distance, then it may be that your PC does not draw all details far away from you. That would then be due to either a setting in the game or due to lack of power in your hardware leading to that details far away are skipped. Hence there may be a cover for them to hide behind that you dont see. Well that's just a theory.
Also consider all the cheats that are infesting the online world and they might be using.