Paganism, witchcraft, and Wicca as portrayed on TV, movies, and popular culture. Buffy, the Vampire Slayer, Charmed, Practical Magic, etc. If you know of a good show or movie, you can recommend it here or discuss it with others.
Some necromancy deals with raising the dead, other communication, still other to cause the dead to rise to destory this plane. It depends really, just like the word witch.