The term Magic[Footnote 1][Footnote 2] has two related meanings. First, it refers to a supernatural force or energy described as "the essence of life and creation. Second, it refers to the practice of harnessing this force to produce changes in reality. An act of magic is called a spell, and the act of performing such an act is called casting. Most supernatural beings are capable of performing magic, as are some mortals, who are referred to as practitioners.
According to Harry Dresden, magic is life's essence; generated by living things, and may be thought of as akin to the concepts of Odic force[Footnote 3] and prana;[Footnote 4] the human heart, soul and emotions are also powerful sources of magical energy. Black magic comes from negative emotions like lust, fear and anger, which are easy to harness. Dresden's magic was harder because it comes from a deeper, truer, and purer source—harder to tap, harder to keep but more elegant and more powerful.
Similar to using firearms, casting spells as a three-step process; gathering energy, shaping it with one's thoughts and feelings, releasing it in the intended direction. In Blood Rites, Dresden remarks tht it can be very difficult for a single individual to handle all these tasks when performing a large spell, so that three practitioners will work in concert to divide the effort.
Practitioners must be confident in their ability and in their motivation in casting a spell; believing that one is unable to do it, or that it's not right to do it, will preclude him from using that spell.
As a side-effect, magic the interferes with the operation of electrical or electronic devices; its severity depending on the complexity of the device and the amount of ambient magic. Although the term "interference" suggests that the effect is temporary, exposure to magic can and often does produce permanent damage to affected devices.(reference needed) Waldo Butters describes it an intensification of Murphy's Law.[Footnote 5](reference needed) It used to be magic caused dairy products to spoil and warts and boils appear on the human skin.(reference needed)
According to Ebenezar McCoy, this phenomenon is caused by the inner conflict of human beings and the resulting magical turbulence-Faerie magic does not harm machinery.(reference needed) Or, more simpply, magic is interwoven in Faeries in a way that it is not in mortals, so that its side effects are different; according to Waldo Butters, wizards are surrounded by a "murphyonic field", closely linked to their healing powers.(reference needed) As a consequence, Harry Dresden often hexes, knowingly or unknowingly, computers, electrical material, and other machinery.
Curses, such as malocchio, entropy curse and the death curse are spells intended to do harm. They need some means of directing the magic at a target; body parts like hair, nail-clippings, fresh blood work best. To make a curse long-lasting, it needs to be anchored to an object or a blood relation.
Really strong curses require three people to cast the spell: one to gather the energy, one to shape it, one to aim it.
Practitioner is a generic term for an individual who can use magic, with no reference to the user's power or skill. There are a number of other terms, however, which do have such connotations.(reference needed)
Most human beings cannot use magic at all; the number of practitioners diminishes with the increase of the power they can command.(reference needed)
- Wizards are practitioners who show the full spectrum of magical abilities known to mortals, and are therefore members of the White Council. The Council grants membership only to the top two percent most powerful practitioners. Yet, even the strongest wizards are insignificant with respect to supernatural heavyweights like the Faerie Queen; very few exceptions, such as The Original Merlin, exist.(reference needed)
- Sorcerers are wizards magically qualifying for the White Council, that do not meet its other criteria for eligibility or have chosen not to accept membership. They are often self-taught or lack the resources and knowledge base of the White Council. The term is sometimes used as a pejorative, with the connotation of a dangerous or destructive individual.(reference needed)
- Minor talents are practitioners with a small magical ability.(reference needed)
- Warlocks are practitioners who have violated one of the laws of magic.
Wizards are very long lived, with a lifespan measured in centuries. Their self-healing capabilities are also extraordinarily high; though they don't heal faster than ordinary people, they heal better. A practitioner's body can recover from injuries that an ordinary mortal never could. Furthermore, the recovery is eventually so complete that sometimes there is no evidence that an injury ever occurred. Wizards can get serious scars, which eventually will be repaired.
In much the same way that people have varying talents for art, science, or music, practitioners have varying aptitudes for different aspects of magic. Harry Dresden is very adept at thaumaturgy (particularly at finding things), but less so at evocation. His apprentice Molly Carpenter, on the other hand, has a knack for veils and psychomancy.(reference needed)
Props and toolsEdit
Though spells are mental constructs, most magical practitioners use various physical objects in casting them; many of them can get extremely complex and difficult to cast properly. The use of props reduces the amount of required mental effort.
A long-duration spell needs to be anchored to either objects, such as Dresden's blasting rod,(reference needed) or people, in which case they need to be blood relatives to either the caster or the target. The Bloodline curse is such a case.(reference needed)
Circles of power are one of the basic tools of magic. An empowered circle creates a barrier that magical forces and beings of the Nevernever cannot cross, preventing magical interference from the outside. Circles can also be used to contain supernatural beings or keep them out.  Setting up circles, gathering energy and aligning forces can be time-consuming.
Names anchor to thaumaturgical links to the being bearing them. Correct pronunciation is essential, and it ultimately has to be told from the Name's bearer. Thaumaturgical links can also be created enchanting a piece from the target; if it is a human being, hair strands, nail clippings, or fresh blood are excellent items. can be used to aim a thaumaturgic spell at the person it was taken from. 
Homunculi[Footnote 6] are objects used to temporarily host a spirit incapable of manifesting a physical form of its own. Some practitioners use fresh corpses,(reference needed) Harry Dresden uses a Cabbage Patch doll[Footnote 7] as a vessel for Ulsharavas.
Blood has a kind of power; a practitioner can use blood to track the person who spilled it. Once it dries, or is excessively diluted, it's harder, if not impossible, to use. Different amounts of blood are needed according to the efficiency and skill of the magic user and how much energy the spell requires.
The Seven Laws of MagicEdit
- Main article: Seven Laws of Magic
- Thou shalt not kill by use of magic.
- Thou shalt not transform others.
- Thou shalt not invade the mind of another.
- Thou shalt not enthrall another.
- Thou shalt not reach beyond the borders of life.
- Thou shalt not swim against the currents of Time.
- Thou shalt not seek knowledge beyond the Outer Gates.
In the seriesEdit
- Main article: Storm Front
- Main article: Blood Rites
In Blood Rites: Harry Dresden was hired by Arturo Genosa to stop Strega from killing with a Malocchio—an Entropy curse. Murphy asked Harry why he can't do the sunshine magic thing like he did on Bianca St. Claire a few years back. Harry said that he tried it again after The War and found out that he needed to be genuinely happy to be able to fold sunshine into a hankie or it does not work.
- Main article: Turn Coat
In Turn Coat, Anastasia Luccio told Harry Dresden how his mother, Margaret LeFay, loved pointing out the ares of "grey" magic, as she called it and questioned their legitimacy. As a consequence, the Senior Council tasked the Wardens with keeping an eye on her.
- Main article: Changes
In Changes, Harry Dresden performed magic in his mind without the use of any props while immobilized after having broken his back and being desperate to rescue his daughter. He first summoned Uriel who cannot help him. Harry then summoned Mab.
- Main article: Ghost Story
In Ghost Story, Harry Dresden tries to figure out how to use magic being a ghost. He had to access the energy, empower the spell with memories. "Working magic as a ghost was all about doing it au natural." With a tracking spell to find Molly, at first he kept finding himself at some place they were at long ago. When he used a current memory and filled it with details, it worked.
Word of ButcherEdit
According to Jim Butcher, "Magic wasn't always screwing up post-WW2 tech. Before WW2 magic had other effects. It sorta changes slowly over time, and about every 3 centuries it rolls over into something else. At one time, instead of magic making machines flip out it made cream go bad. Before that magic made weird moles on your skin and fire would burn slightly different colors when you were around it."
- ↑ Magic - wikipedia
- ↑ Magic in fiction - wikipedia
- ↑ Odic force - wikipedia
- ↑ Prana - wikipedia
- ↑ Murphy's Law - wikipedia
- ↑ Homunculus - wikipedia
- ↑ Cabbage Patch dolls - wikipedia
- ↑ 1.0 1.1 1.2 Storm Front, ch. 2
- ↑ Fool Moon, ch. 33
- ↑ 3.0 3.1 3.2 Blood Rites, ch. 27
- ↑ Fool Moon, ch. 10
- ↑ Storm Front, ch. 1
- ↑ Cold Days, ch. 19
- ↑ The Warrior
- ↑ 8.0 8.1 Summer Knight, ch. 19
- ↑ White Night, ch. 41
- ↑ Grave Peril, ch. 1
- ↑ Blood Rites, ch. 9
- ↑ Blood Rites, ch. 4
- ↑ 13.0 13.1 Changes, ch. 29
- ↑ 14.0 14.1 Storm Front, ch. 6
- ↑ Turn Coat, ch. 19
- ↑ "Last Call"
- ↑ The Warrior
- ↑ Storm Front, ch. 11
- ↑ 19.0 19.1 Small Favor, ch. 04
- ↑ Death Masks, ch. 8
- ↑ Cold Days, ch. 47
- ↑ Ghost Story, ch. 10
- ↑ 23.0 23.1 Fool Moon, ch. 4
- ↑ 24.0 24.1 Cold Days, ch. 27
- ↑ Blood Rites, ch. 3
- ↑ Storm Front, ch. 9
- ↑ Blood Rites, ch. 23
- ↑ Turn Coat, ch. 28
- ↑ Changes, ch. 30
- ↑ Ghost Story, ch. 21
- ↑ Jim Butcher Dragon*con Q&A