Subgenres of horror films

Cannibalism or Cannibal Films
Classic Horror
Creature Features
Demonic Possession
Dracula
Erotic
Frankenstein, other Mad Scientists
Ghosts
Gore
Gothic
Haunted House, other Hauntings
Halloween
Macabre
Monsters
Older-Woman-In-Peril Films ("Psycho-Biddy", aka 'Hag Horror' or 'Hagsploitation')
Psychic Powers
Psychological Horror
Reincarnation
Satanic Stories
Serial Killers
Slashers or "Splatter" Films
Supernatural Horror
Teen Terror ("Teen Screams")
Terror
Vampires
Witchcraft
Wolves, Werewolves
Zombies