(Original Review, 1980-10-22)
Boy, are you going to get answers to this/ query! (Darkover tends to arouse very strong opinions). The Darkover stories comprise about a dozen novels and a few shorts by Marion Zimmer Bradley, plus a lot of (fortunately) mostly unobtainable fan fiction. Darkover is a harsh world with a few cities and a basically feudal/manorial social structure complicated by the presence of psionic faculties ("laran") in most of the aristocracy and many of the commoners.
If you're into stuff like this, you can read the full review.