As with all his books, Pratchett takes a very well known part of mostly English folklore, and turns it on its head. He presents witches as they may really have been - strong willed and knowledgeable women that thewhole village were terrified of. However, this is the disc world, so of course they can also perform magic, although not always as intended.

A great read, and you do not have to have read any of the other books in the series to appreciate it.