Always two there are, no more, no less?

i dont understand this very well. does this mean that there can only be two sith at one time in the whole galaxy, or is it just describing a master and apprentice thing?

as it was clearly said in TPM:

the sith can only be with two, no more, no less, a master and an apprentice

every sith is either a master or apprentice...right?

That's right, though bear in mind 'Apprentice' just means the junior one, not necessarily someone still in training.

George Lucas describes it thusly:

"One of the themes throughout the films is that the Sith lords, when they started out thousands of years ago, embraced the dark side. They were greedy and self-centered and they all wanted to take over, so they killed each other. Eventually, there was only one left, and that one took on an apprentice. And for thousands of years, the master would teach the apprentice, the master would die, the apprentice would then teach another apprentice, become the master, and so on. But there could never be any more than two of them, because if there were, they would try to get rid of the leader, which is exactly what Vader was trying to do, and that's exactly what the Emperor was trying to do. The Emperor was trying to get rid of Vader, and Vader was trying to get rid of the Emperor. And that is the antithesis of a symbiotic relationship, in which if you do that, you become cancer, and you eventually kill the host, and everything dies."

The point being that if there are ever more than two Sith, they become too divisive to be effective.

i shtere a difference between a sith and a regular dark jedi?

Only in name but the practical effect is the same- Dark Siders divide amongst themselves.

Ok but how about in Ep3 ? There will be dooku at first. Then he will die so the emperor will pick up grevious or will he still wait to recruit anakin ? Because we all know that both will be villains in this ep3. And if the emperor plans on recruiting anaking for a long time then it means grevious is not a sith or either the emperor is taking him for a short term job hoping anakin will kill him later... lot's of confusion in this.

I heard somewhere that Dark Jedi were just Jedi who had turned bad but still had the same powers as regular Jedi. Sith have a special magic they use that no one else knows about, so after all the Sith are destroyed there can be no more Sith because no one else knows about the magic. Don`t know if it`s true or not, I just heard it somewhere.

I'm assuming that General Grevious will be incorporated into Anakin to become Darth Vader. That's the perfect link to how Anakin gets his techno gear. So Grevious has to be destroyed in some fashion to make way for Darth Vader to rise.

grevious is not a sith. hes in charge of the separitists army and soon the clones. yes he fights with lightsabers i know, but thats only because he can and will. he doesnt have any jedi powers at all, just saber skill

Correct, as DA said, Greivous is not a sith. He weilds lightsabers and possesses some capacity to predict a jedi's movement, but is not, as far as I know, force-sensitive.

We have seen no evidence of any 'special Sith magic'.

what about sith magic beans?

they were eaten by the sith dog

Except for them, of course.

Originally posted by DARK ASSASSIN
grevious is not a sith. hes in charge of the separitists army and soon the clones. yes he fights with lightsabers i know, but thats only because he can and will. he doesnt have any jedi powers at all, just saber skill

that is stupid that is dumb...what the **** is lucas thinkin?...the lightsaber is suppose to be a weapon of a jedi and before u some of u say but the sith have them...yea the sith who are dark jedis and force sensitive...i dont beleive a non-jedi is gonna have a lightsabre

We've kinda had this argument already. It does indeed appear to be the case, so presumably Grievous has some very hi-tech co-ordination for his sabres.

Still, we shall see.

so what if it's the weapon of the jedi? can't mean a smuggler can't use it! just put the bright side in the other guy ... not THAT hard

just that if you fight a jedi with it ... you're dead meat

Han Solo used a lightsaber in ESB. Why would it be so hard to for a cybernetic soldier to use one?

There is a difference between using one as a cutting tool and using it to duel Jedi. But even so, it seems to be possible.