The undead are beings that even though are definitely deceased demonstrate some aspects of still being among the living.
This grouping will include ghosts, spirits and corporeal beings such as vampires and zombies. While ghosts, spirits and apparitions can spook and terrify us into believing we are losing our minds - vampires and zombies can physically attack us and sometimes transform us into one of them.
It would seem very common in tales that most ghosts and spirits become a hassle or threat to the living only when they seek closure over an evil deed that was once carried out against them while they were still among the living.
Since they are essentially sentenced to exist in limbo while forever waiting, being tortured and taunted with the lack of resolve and/or vengeance, a means to an end is the only thing they desire and seek.
Others are just evil to the core for absolutely no reason - perhaps puppets or mere soldiers at the mercy and command of a much greater evil.
Physically enabled beings such as vampires and zombies have terrorized and forced us to try and overtime prove some very effective techniques to help the living guard against them.
Depending on which story you read though, it is very difficult to feel 100% confident that most, if any of these methods would actually work. That is probably why in many accounts, the preyed upon often try to use many if not all defense methods hoping that something will finally do the trick.
THE A-Z LIST
Baital - Human looking, brown skin, boney with bat wings
Banshee - A young woman, a distinguished matron or a tousled old hag
Black Dog - Extremely large, black canine ghost
Boogeyman - Shadows that transform into a feared monster
Cu Sith - Enormous, dark green hound
Diwata - Male or female guardian spirits
Draugr - Ghosts of fallen Vikings
Drekavac - Dog`s body with large kangaroo-like hind legs
Fairies - Human-looking spirits with magical powers
Ghouls - Undead, decomposing human body
Grim Reaper - Skull face wearing a black cloak and hood
Gwyllion - Ugly female spirits that relish in mischief
Headless Horseman - A horse riding ghost with no head
Inugami - Canine spirit
Kitsune - Fox spirit with magical powers and many tails
Lich - Skeletal looking and extremely clever animated corpse
Mummies - Corpses wrapped in thin strips of linen
Oni - Huge bodies, horns, wide mouths
Skeletal Warriors - Weapon yielding humanoid skeletons
Tengu - Head of a beaked man with the wings and talons of a large crow
Tokoloshe - Child-size body, pale skin, eyes and brain removed
Vampires - Human looking creatures in need of blood to survive
Varcolac – Large undead wolf demon
Wendigo - Bony body, crooked teeth, disfigured face
Wraiths - Dark ghostly bodies of ultimate evil
Yuki-Onna - Ghost of a beautiful woman with see through skin
Zombies - Reanimated corpses