This is too important to just leave to my browser’s bookmarks. I just found this absolutely marvelous online dictionary of narrative mechanisms called Television Tropes & Idioms. Despite the name it is not just about TV, but about story telling in all mediums, including games. And every definition I’ve encountered so far is absolutely spot on. And in discussing devices and twists it makes mincemeat of the opinions of producers (“the punters only like happy endings“) and viewers (“they can’t bring back Joe, his brains are scattered over three continents and a small asteroid called Katie”) alike.