Making Things Happen
Types of Magic
The simplest way to let another person use a spell is to cast it on an item. These items do not cast magic on the spot, but they have an aura of effect, like a shield or a good luck charm. They will consistently produce that effect until they come into contact with something that makes them stop. Artefacts will be magical regardless of who holds them, because they do not depend in any way upon the magical abilities of that person. On the down side, they are obvious to those familiar with magic, because they do give off an aura of magic, which is perceptible to most who use it frequently, though successfully identifying the type of magic in question is a bit more difficult.
Potions are one-shot spells that can be ingested to produce an effect. Like artefacts, they are not dependent on the power of the user, and can be used by anyone, once they have been produced. A potion can only affect the individual who ingests it, and it is completely possible to have an allergic reaction to one, based on the ingredients needed to contain the spell. The effects of potions are temporary, some ninety percent of the time, with the other ten being things that have caused irreversible alterations to the body, such as dramatic aging or limbs falling off. A potion that imparts a power or active enhancement to the user, such as increased strength or a shield, will generate an aura of magic around the user, but one that imparts a passive alteration, like a transformation or sleep, does not.
Powers are those nifty things that magical creatures don't have to study in order to use. They're innate to the species, or in some cases of mutation, to the individual. Powers can do anything that can be done with any other spell, but require less effort and energy, because they're a native function. Using a power will generate an aura, and having powers will usually mark one to a certain degree, in the eyes of other magical or magic-using creatures. Frequently, the more potent the power, the more obvious the user is, unless, obviously, the power is stealth-related.
Spells are the basis of all non-native magic. If it's not a power, it involved a spell, at some point. All spells will generate an aura, when cast, but not all spells will leave a residual aura, afterward. Basically, if the spell has a continuous effect, it will have a continuous aura, but only rarely will a one-shot spell, like a fireball or a mending spell, have an aura after the effect has happened. Anything that can be reversed by removing the spell will have an aura.
When one needs to cast a spell quickly, there are few things better for the job than a wand. A wand can only be used by an individual with some innate capability for magic, and usually contains one or two spells, never more than five, and that only in cases of the very most powerful which are extremely rare (read 'no, you don't have one'), which can be activated with a particular word or gesture. A wand will lack an aura until it is used, at which point it will flare.
Types of Beings
Naturals are those who have no magic in them, but that which gave them life. They cannot perform spells, but can use artefacts and potions. Most humans are naturals, as well as many other species, sentient and otherwise, from the aptly-named 'natural planes'.
Mages are creatures who, by their species and other factors, should have been naturals, but through some mutation, have gained magical powers. This does not include creatures who are half-natural with one innately magical parent, but does include children of other mages. It is thought that some magical creatures may have arisen from mage lineages of other species.
These creatures naturally have magical powers, of some sort, or otherwise contain magic as an innate part of their being. Dragons, fae, kitsune, and most other legendary creatures of the natural planes are magical creatures of some sort.
The origins of the deities are unknown, though there are many stories. In essence, they are the forces that make the world function as intended. Some are able to give a part of their power to selected other creatures, whether those creatures initially had magic or not, and to instruct those individuals to attend to certain things, on their behalf, for a time.
Literally, 'miracle makers'. These are the badassinest badasses ever to give form to magic. Where a wizard practises theory, a thaumagenist produces theory, delving ever deeper into the mysteries of why magic works and how to better harness it for various applications. It is extremely unlikely you will ever meet one, because they are extremely distracted and distractable sorts, and rarely remember to go to functions, because they often forget to eat lunch, because they've found some exciting new theory.
Wizards study magic, on the theoretical level. They are known for taking complex spells, and making them as simple as possible, and thus easier to both teach and perform. They are most akin to cut and paste coders, taking parts of several spells and combining them to get the necessary effects. While this may seem to be a minimal effort, a wizard usually has enough going on that when he enters a room, his aura will turn heads. Even a natural will recognise the presence of magic, around a wizard.
Sorcerers are the height of awesome, for most people. Court wizards in the Natural planes are often actually sorcerers, not making magic, but performing it exceptionally well and efficiently. A sorcerer is often capable of making artefacts, wands, and potions of middling quality.
Enchanters are those with a basic understanding of magic and the skill to perform many common spells, like discovering illness in animals and locating lost property. An enchanter is so known for the ability to make basic artefacts and some potions, though they lose potency fairly quickly.
An adept has magic, and possibly powers, but does not have much formal training. While basic magic comes fairly easily, it does not manifest without cause, whether training or peril. An adept cannot produce any magical items, as they lack the control required, but if given a magical item, they will not likely experience any difficulties using it, if given instructions.
Proxies may or may not have any magic of their own, but they have been granted a power and a task by a deity, usually one they worship, although there have been some terribly amusing incidents, in the past. The powers of proxies are tied to the responsibilities of the deity and to the task the proxy has been given. As so called 'holy magics', those powers may operate somewhat differently than the others described here.