Gods and Demons Wiki
To be honest, no one truly know what magic is, not even the gods themselves, and because of that, we call it magic. In its most simplest of explanation, magic is the unknown, the world's greatest [Mystery] that is hidden from all existence, and only those with connection to the primordial source might have a clue of its origins. And knowing who these primordial entities are, I doubt they would actually enough to tell us, if not outright lie and tell a bullshit story right at the spot just to mess with us.
Matt Wright

Magic, also known as Magick or Sorcery, is a method of controlling the natural world (including events, objects, people and physical phenomena) through mystical, paranormal or supernatural means. The belief that one can influence supernatural powers, by prayer, sacrifice, or invocation dates back to prehistoric religions and it can be found in early records such as the Egyptian pyramid texts and the Indian Vedas.

Magic is sometimes practiced in isolation and secrecy and often viewed with skepticism and suspicion by the scientific community. In non-scientific societies, a perceived magical attack is sometimes employed to explain personal or societal misfortune.

One who practices magic that derives from supernatural or occult sources is usually known as a magician or sorcerer, but the labels enchanter, wizard, warlock, mage, magus, necromancer or thaumaturgist may also be used. Ceremonial Magic or Ritual Magic is characterized by a wide variety of long, elaborate and complex rituals or ceremonies and a variety of necessary accessories to aid the practitioner.

Black Magic (or Dark Magic) is a form of sorcery that draws on malevolent powers, and may be used for dark purposes or malevolent acts that deliberately cause harm in some way. It is usually associated with the "Left-Hand Path" belief systems, which value the advancement and preservation of the self and the pursuit of temporal and terrestrial goals, rather than the "Right-Hand Path", which elevates spirituality, the strict observance of moral codes and the worship of deities.

Most witches would agree that in order to be able to carry out magic, the mind first needs to be trained in the techniques of meditation, visualization, concentration and imagination. There are three basic sources of natural energy or power used in magic: Personal Power (the power that resides within our own bodies, our life force and willpower), Earth Power (the power that resides within our planet and its natural products, such as stones, trees, wind, fire, water, crystals, oils and scents) and Divine Power (the spiritual power that is charged and channeled by the Goddess and the God).