Spell

Wingardium Leviosa, a levitation charm.

» List of Spells

A spell is a magical action often accompanied by an incantation (usually—but not always—Latin based; exceptions include Obliviate or Point Me) that makes use of the magical force of the wizarding world in order to accomplish extraordinary feats ordinary people (Muggles) cannot perform, for example levitating objects, conjuring fire, or stunning a person. Spells often have some kind of physical representation in the form of light and as such can usually miss, be dodged, or blocked with an object (including another spell). The action of performing a spell is referred to as casting.

Page adapted from Spell at the Harry Potter Lexicon.

Usage

Now, don't forget that nice wrist movement we've been practicing! The swish and flick! And saying the magic words properly is very important, too — never forget Wizard Baruffio, who said 's' instead of 'f' and found himself on the floor with a buffalo on his chest.

—Professor Flitwick in Charms Class, Harry Potter and the Philosopher's Stone

Normally, spells require three main factors to be properly accounted for in order to succeed: wand movement, incantation and intent. If one does not move their wand in the correct way, does not speak the incantation properly and/or cannot retain their desired outcome in their imagination during casting then the spell will fail or backfire.

It should be noted that spells can be performed with or without speech and wands, though non-verbal and wandless spells are much more difficult and hence are usually not taught to practitioners until they reach a more advanced level, such as the sixth year of study at Hogwarts.

Most incantations derive from the Latin language (such as Accio) but there are also some English incantations (such as Obliviate or Stupefy).

A simplified analogy for the differentiation between Transfiguration and Charms is the difference between form and function or matter and energy; one is concerned with what the object is (its form - Transfigurations) whilst the other is concerned with what the object is doing (its function - Charms).

Appearance

When performed, spells usually evoke light from the wand they are cast with, such as the tell-tale red of Stupefy or green of Avada Kedavra. However, some spells, such as Accio and Silencio, produce no visible intermediate effect. Some spells also make loud noises when cast, although it has been noted that "bangs and smoke were more often the marks of ineptitude than experience."

Durations

Typically, spells brought about through magic have a certain time limit placed upon them. This means that effects and after-effects magically induced by them are not meant to last, since spells like Expelliarmus only operate brief and swift, while spells like Stupefy and Petrificus Totalus wear off eventually. Counter-curses can also end a designated spell's effect. Likewise, most spells whose effect has yet to diminish would disappear at the moment of the caster's death

Origin

New spells can be crafted by wizards and witches, though it is a difficult and dangerous practice.

Classification

Below is a list of all known categories that spells can be assigned to. It should be noted that the following categories are not necessarily mutually exclusive to each other; i.e. whilst a spell can't be both a charm and a transfiguration, a jinx can be a healing. Certain spell types also belong to separate classification schemes to others. For example: Petrification is dark magic of the most advanced kind but it is also Transfiguration, Melofors is both a Jinx and a Conjuration, Fiendfyre could be considered a Charm as well as a curse and many healing spells could also be considered either charms or transfigurations. Hence, charm vs. transfiguration is one method of classification and counter-spell vs. jinx/hex/curse vs. healing spell a different one.

Spell Type	Defining Feature	Notes	Example
Transfiguration	Alteration of the object's form or appearance	Spells of this group may be separated into true transfiguration spells (where an existing object is altered) and conjurations, where the desired object is seemingly transfigured out of thin air.	Vera Verto - a true transfiguration spell that changes animals into water goblets. Avis - a conjuration that produces a flock of birds
Charm	Alteration of the objects inherent qualities i.e. its behaviour and capabilities.	When cast by an experienced practitioner, charms appear to usually have fairly long-lasting effects.	Expelliarmus - the Disarming Charm, so-called because it changes its object's (the opponent's) quality from armed to disarmed by separating them from their wand.
Jinx	Minor dark magic; spells whose effects are irritating but amusing, almost playful and of minor inconvenience to the target.	Jinxes can only be maintained as long as the caster keeps eye contact.	Impedimenta - the Impediment Jinx, which (appropriately) impedes the forward motion of an object.
Hex	Consistently affects the object in a negative manner; has a connotation of dark magic, but more so than a jinx. Major inconvenience to the target.		Anteoculatia - a hex that causes antlers to sprout from the object's head.
Curse	The worst kind of dark magic, intended to affect the target in a strongly negative manner.		Avada Kedavra - a.k.a. the Killing Curse, which kills the victim.
Counter-spell	Inhibition of the effect of another spell.	There are six types: Counter-jinxes, counter-curses, counter-charms, untransfigurations, anti-jinxes and undifferentiated counter-spells. Whilst nomenclature is complex they all share the common trait of inhibiting another spell.	Finite Incantatem - a widely-employed counter-spell that terminates spell effects in general.
Healing spell	Improves the condition of the living object.		Episkey - heals minor injuries

A simplified analogy for the differentiation between a transfiguration and a charm is the difference between form and function or matter and energy; one is concerned with what the object is (its form - transfigurations) whilst the other is concerned with what the object is doing (its function - charms).