thats why i used the term "force user", because they could be either a Jedi or Sith, which by the way, are just organizations within the force user community. There can be a force user that is neither a Jedi or Sith, and can still be light or dark side force user, and still not be a Jedi or Sith, just a force user.
The light saber alone doesn't make a force user a Jedi or Sith, a Jedi does what Jedi do, and Sith do what Sith do. It is possible to exist between the two, and not be a member of either, and still have a lightsaber, as long as you have the knowledge to build a lightsaber, you still do not have to be a Jedi or SIth to have it.
General Grievous was neither a Jedi or Sith, but he had an abundance of lightsabers.
The very existence of flamethrowers proves that some time, somewhere, someone said to themselves, "You know, I want to set those people over there on fire, but I'm just not close enough to get the job done." -George Carlin