An interesting thread over at absolutewrite (to be known as AW from now on) this morning. Essentially, the question raised is what is horror? A member has described their book which features angels, demons, Hell, death and all that fun stuff. They see it as more action than horror but apparently everybody they have described their book to hears demons and thinks horror. I don't. I think fantasy. Dark fantasy, yes, but not horror.
Horror gets under your skin, or should do, anyway. Horror should literally be that - horrifying. There's a place and obviously a huge readership for paranormal romance or sexy heroines kicking vampire ass, but that's not horror to me. I want my horror to stay with me long after I've finished writing or reading it. Take King's Pet Sematary, for example. A truly horrifying story. The worst part of that horror isn't (spoilers if you haven't read it...although I have to ask why you haven't read it) Gage's death or subsequent return. The horror is in Louis' developing insanity, in his grief and in the inevitability of events. You can call it Fate if you like. Whatever its name, you can't change what's coming by the end of King's book. You either get out of its way or it kills you. THAT's horror.
So what about gore and physical violence? Said AW member states: 'Take zombies: how the heck are zombies horror? Gorey? (sic) Sure, but that whole thing is more action/post apocalyptic than horror'. Obviously there's some truth in this. Anyone who's seen more than five minutes of pretty much any zombie film knows there's a lot of blood and snot and shit flying about when the dead start walking and start munching. That's not the true horror of the zombie world, though. The horror is what you bring to it.
You're in the zombie world. You've probably lost your family and friends; you have no food, probably no weapons and very little chance of making it to safety. And at any minute, you could be eaten alive. There's your horror. It comes from being in such a nightmarish situation, not just from the blood. Gore and violence are often part of horror, but they don't make it what it is. Don't believe me? Watch the relatively bloodless Night of the Living Dead, and then tell me that's not horror.
Ultimatey, horror should stay with the reader or viewer. It should haunt them. Put simply, horror should horrify. If it doesn't, chances are it isn't horror.