One thing I’ve been considering with worldbuilding, specifically regarding magic, is the various broad types or varieties of magic. I’ve been primarily thinking in a historical perspective, but to some degree purely fictitious as well. The following is off the top of my head, so is clearly not a comprehensive collection by any means. It is simply my attempt to categorize or classify different types of magic sources in fairly broad terms.
I will try to avoid certain words commonly associated with magic—ex. sorcery, witchcraft, wizardry—because they are very imprecise and are often used both interchangeably and for a variety of different magics.
My general terminology for magics that use rituals made up on the spot. In these cases, often the rituals are never the same twice as they are based on what the mage feels is right at the time. Terry Pratchett’s witches are a good fiction example, particularly the witches as depicted in the Aching books.
Historically, alchemy is a mix of mysticism, natural philosophy, and early scientific testing. For these purposes, I include any magic that gets its power from mixing ingredients to produce elixirs—whether potions, pills, or unguents—or chemistry, metallurgy, or related magical products. This can take the form of the laboratory (whether “traditional” magic lab or modern), the herbalist working in a hut or open fire, or the brewer/vintner mixing special ingredients into beers and wines to make magic drinks.
Historically, the study of the stars and planets to determine the future and predict the fates of individuals. Usually found the same way in fiction. One of the most famous astrologers in history was Dr. John Dee of England; and the practice was banned in England during Elizabeth I’s reign due to the succession question, predicting the queen’s death was a capital offense.
Quite possibly one of the earliest forms of magic in history, blood and magic have been associated for millennia. According to some, blood can provide energy to fuel spells; to others, it can be used to control the person it came from. To many cultures it was believed to be one of the most potent forms of magic.
Chi (or Ki)
The power of chi is the foundation of all wuxia stories and movies. This internal energy is, in the stories, most often harnessed through martial practice. Control of the body coming from martial arts leads to control of the mind and the inner energy. This is most famously channeled to great physical feats—strength, leaps, even a form of flight—or healing.
In some cases, the source of magic is the gods. Divine magic often relies on maintaining the deity’s or deities’ mandates and goodwill. Falling out of favor with the divine leads to removal of magical power. Some uses limit divine magic to healing, other uses restrict the mage to spells associated with the god’s areas of influence.
According to many traditions, there is magic inherent in the elements. Traditionally these are air, earth, fire, and water in the west and Hinduism; earth, fire, metal, water, wood in much of Asia. Often a sample of the element is necessary to invoke the magic, but not always.
Based on the idea that gemstones possess magical potential, this category of magic draws power and spells from the stones. Each stone is held to have different properties and associations that it can be used for, ex. amethysts as protection from poison. Often, I refer to this group as lithomancy. It appears regularly in history in many cultures as well as in fiction, MZB’s Darkover books have a variation, for instance.
I use the term hermetic here both in reference to its use in history (the Hermetic Order of the Golden Dawn) and because of a background with White Wolf’s Mage: the Ascension. This type of magic emphasizes ritual, specifically exact, repeated ritual. In a way, I suppose it is akin to alchemy in that it is relatively scientific with the idea that performing the same ritual, speaking the same words, moving the same way will produce the same magical result every time. It’s the opposite of Ad Hoc magic in its exactitude. Often it involves the “Laws of Magic” idea, ex. Law of Contagion, Law of Similarity, etc.
Magic for fans of spreadsheets and flow charts. The Kabbalistic view of magic involves potentially hundreds of variables including the position of stars, the sun, phase of the moon, locations of metaphysical planes, associations of magical materials with said planes or the subject or the caster, proper words, and proper ritual. There’s a very good systematization of this magic in the old third edition GURPS Cabal book, spreadsheets not included.
Magic that draws on ley lines, which I sometimes refer to as geomancy, for power. This is, obviously, a fairly common magic view in history and the modern world as it still has adherents. Power is drawn from the lines, and greater power from nodes (the places where lines cross; the more lines, the more power). Some believe ley lines are an element of dowsing, among a variety of other things. A variation is used by Robert Asprin in the M.Y.T.H. Inc. series.
Psychic magic draws on internal, mental energy to fuel magic. We commonly associate this with divination, fortune telling, clairvoyance, telekinesis, psychometry, precognition, scrying, and related abilities. As we can tell in many places, psychic magic appears often in history and the modern world, psychics and mentalists were a dime a dozen at one time and are still moderately popular for entertainment purposes.
Alongside blood magic, sex magic is perhaps one of the oldest in the world. Associations of sex and magic go back millennia and can be found in Tantric beliefs (famously) as well as Mesopotamian beliefs and branches of Taoism, Paganism, and Buddhism at the very least. Even some more esoteric branches of Christianity, particularly Gnostic Christianity, have embraced the concept. In modern fiction, it is often used to fuel other spells, initiate scrying and divination, or create magical bonds between individuals.
Sigil (or Word) Magic
Another very old magic, the idea that words and symbols have magical powers is ancient. We have records of spells and curses from ancient Greece and Rome, for instance, that are still extant and symbols in Celtic sites that seem to have magical purpose along with Norse and Saxon rune magic. Perhaps the four most common uses are varieties of blessings, curses, protection, and reading the future. I also include tattoo magic, inscribing magical sigils/words on the body, in this broad category.
Spirit (or Ghost) Magic
Magic that involves natural spirits or spirits of the dead would fall into this category. I include both necromancy—attempts to contact, acquire information from, and protection from the dead—and shamanism—attempts to call upon natural spirits to bless, curse, or heal—in this group. Modern conceptions of necromancy—raising the dead, creating undead hordes—would also be included. Jonathan Stroud’s Bartimaeus trilogy is a great fictional example of this magic, as is Book 11 of the Odyssey in which Odysseus calls upon the spirits of the dead for information.
In the Western world, tree magic is most closely associated with the Celts. They held the view that various kinds of trees, and other plants (ex. ivy), held magical properties. Use of the specific plant could bring about magical effects associated with the plant(s) involved, much like gem magic using plants instead. The Celts also used symbols that represented the trees in some cases. I have seen some things that associate tree magic with the Romany as well, but I haven’t been able to confirm this as yet.
Edit (8 July 2016)
Forgot Music Magic, but thinking it could be considered an effect or variation on Ad Hoc or Hermetic, depending on how it is used.