There are three groups who can control supernatural power: sorcerers, wizards, and the karelian species. The first two are considered magicians.
Anyone with magic talent is a magician, whether they’ve developed the talent (becoming a wizard or sorcerer) or not. The term magician can mean nothing to a wizard or sorcerer or can be used to imply they’re an untrained or unskilled charlatan. It is most often used to refer to valend wizards (see below).
These rare magicians perform magic by force of will and understanding and subsequently have no methodology beyond instinct. They do not cast “spells,” use items to assist them, or need to speak or make gestures, though some do as a matter of style or preference.
Their only limitations are what they know, their imagination, strength, and endurance. They can be a danger to themselves or others precisely because their power is not regulated by spells. Most come to power on their own and without a teacher.
Those who use spells are called wizards and are much more common than sorcerers. Words, gestures, items like a wand or staff, and physical materials are generally used to perform magic, and they are in need of spell books. They must be trained, usually in a Wizards Guild. They can learn spells from different spheres of magic but typically start with just one.
The art of creating magic items is called valendry. Magicians who have not passed the final tests to become a wizard are considered to still be learning and are called valend wizards as a result (valend means one is still in training). Those who never pass are forbidden from performing magic except by enchanting items and thus give their name to the art.
The karelian species can control supernatural forces through innate ability given to them by the gods. Since they have a well-developed sixth sense, they are attuned to this energy. This includes spirits and undead, for which their affinity has made them infamous. Their ability to separate their own souls from their bodies for brief times has frightened many despite their good nature.