Spellcasting 101: Schools of Magic

As a spellcaster, there are several main fields of study in which magic falls under (Using the definition familiar with the Dungeons and Dragons RPG. Note other RPG may categorize the fields differently). Most individuals will agree that there are some 8 major fields of magical disciplines, with the 9th being a universal school.

Abjuration: Magics are mostly concerned with protective spells. A spellcaster specialized in the field is an Abjurer. 

Alteration/Transmutation: Magics that change the properties of an item, creature, or condition. A spellcaster specialized in the field is a Transmuter.

Conjuration/Summoning: Conjuration magics bring forth non-living matter or effects forth which can also include healing forces and spirits. Summoning magics bring forth or the attention of living creature or powers. A spellcaster specialized in the field is a Conjurer or Summoner.

Divination: Magics involving knowledge of the past, present, and future fall under this field of study. A spellcaster specialized in the field is a Diviner.

Enchantment/Charm: Charm magics influence individuals through mind effecting compulsion. While Enchantments can imbue items or creatures with magics. A spellcaster specialized in the field is an Enchanter.

Evocation/Invocation: Magics that draw power of the natural energies and forces found in the universe (earth, fire, water, air, positive/negative energies, etc.). A spellcaster specialized in the field is an Evoker/Invoker.

Illusion/Phantasm: Magics that alter the perception of reality. It includes figments which create false sensation, Glamers which change sensory qualities, Phantasms which are mental impressions, and Shadows which are semi-real creations and effects. A spellcaster specialized in the field is an Illusionist.

Necromacny: Magics dealing with life, death, undeath. A spellcaster specialized in the field is a Necromancer.

Universal: These spells contain one or more of the other fields.

Beyond these basic fields, there are hundreds of schools which group spell under their particular effects, cultural influences, spellcasting technique, themetic effects..

Blood Magic: Spells dealing with the inherent magical properties of blood.

Chronomancy: Spell dealing with time effects. A spellcaster specialized in the field is a Chronomancer.

Elementalist: Spells dealing with
an natural elements. A spellcaster specialized in air magics are Aeromancers, earth magics are geomancers, fire magics are pyromancers, and water magics are hydromancers. Other variationa could include Storm,
Seas, Sand, Light, Darkness, Wood, Steel, Magma, Ooze, Ice, Minerals, etc.

Demonologist: Spells dealing mostly with calling forth forces and spirits and supernatural spirits. Usually known for trafficking with a variety of supernatural beings.

Digitologist: Spells cast using mathematical formulas.

Dragon Magic: Spells dealing with magics the emulate or associate themselves with the abilities of dragons.

Gem Magic: Spells dealing with the inherent magics properties of gems and precious stones.

Runic Magic: Spells using a certain number of glyphs that are associated with a number of supernatural effects.

Sonomancy: Magic dealing with sonic based effects. A spellcaster specialized in the field is a Sonomancer.

For Divine spellcasters the main eight disciplines do apply, but are usually organized by themes associated with their Divine Patrons. Such themes are Sun, Moon, Healing, Magic, Nature, Knowldege, Death, Creation, Weather, etc.