In early modern Europe, witchcraft came to be seen as a vast diabolical conspiracy against Christianity, and accusations of witchcraft led to large-scale witch-hunts.

Academically, the concept of witchcraft is normally treated as a cultural ideology, a means of explaining human misfortune by blaming it either on a supernatural entity or a known person in the community. It is recognised, however, that many of the diabolical stereotypes surrounding witchcraft had evolved out of more benign pre-Christian beliefs regarding spirits and the other-world, and that some of those accused as Witches were in fact healers or seers with practices rooted in these same beliefs. The term 'witchcraft' has also been applied to cultures outside Europe, to describe similar ideologies of supernatural misfortune and blame, as well as to describe a wide variety of magical and shamanistic practices, generally dealing with spirits or deities, the afterlife, magic and ritual.

From the mid 20th century on, a growing number of people have come to identify with the term "witch", many seeing witchcraft as a religion with possible pre-Christian roots (see below, under Neopaganism).

The terms 'witch' and 'witchcraft' have slightly different meanings in different fields of study.

Historians of European witchcraft have found the anthropological definition difficult to apply to European and British witchcraft, which doesn't match African models. The presence or absence of magical techniques seems to have been of little concern to those participating in witch trials, and some of the accused really had attempted to cause harm by mere ill-wishing.

As in anthropology, witchcraft is seen by historians as an ideology for explaining misfortune, however this ideology manifested in diverse ways. There were a few varieties of witch in popular belief, and a few types of people accused of witchcraft for different reasons. Richard Kieckhefer places the accused into three categories: Those caught in the act of positive or negative sorcery; well-meaning sorcerers or healers who lost their clients' or the authorities' trust; and those did nothing more than gain the enmity of their neighbours. To these Christina Larner adds a fourth category: those reputed to be Witches and surrounded with an aura of witch-beliefs. Éva Pócs in turn identifies three varieties of witch in popular belief:

* The 'neighbourhood witch' or 'social witch': a witch who curses a neighbour following some conflict.

* The 'magical' or 'sorcerer' witch: either a professional healer, sorcerer, seer or midwife, or a person who has through magic increased their fortune to the perceived detriment of a neighbouring household; due to neighbourly or community rivalries and the ambiguity between positive and negative magic, they can become labelled as 'Witches'.

* The 'supernatural' or 'night' witch: portrayed in court narratives as a demon appearing in visions and dreams.

'Neighbourhood Witches' are the product of neighbourhood tensions, and are found only in self-sufficient serf village communities where the inhabitants largely rely on each other. Such accusations follow the breaking of some social norm, such as the failure to return a borrowed item, and any person part of the normal social exchange could potentially fall under suspicion. Claims of 'sorcerer' Witches and 'supernatural' Witches could arise out of social tensions, but not necessarily; the supernatural witch in particular often had nothing to do with communal conflict, but expressed tensions between the human and supernatural worlds, and in Eastern and Southeastern Europe such supernatural Witches became an ideology explaining calamities that befell entire communities.

Practices to which the witchcraft label have historically been applied are those which influence another person's mind, body or property against his or her will, or which are believed, by the person doing the labelling, to undermine the social or religious order. Some modern commentators consider the malefic nature of witchcraft to be a Christian projection. The concept of a magic-worker influencing another person's body or property against his or her will was clearly present in many cultures, as there are traditions in both folk magic and religious magic that have the purpose of countering malicious magic or identifying malicious magic users. Many examples can be found in ancient texts, such as those from Egypt and Babylonia, where malicious magic is believed to have the power to influence the mind, body or possessions, malicious magic users can become a credible cause for disease, sickness in animals, bad luck, sudden death, impotence and other such misfortunes. witchcraft of a more benign and socially acceptable sort may then be employed to turn the malevolence aside, or identify the supposed evil-doer so that punishment may be carried out. The folk magic used to identify or protect against malicious magic users is often indistinguishable from that used by the Witches themselves.

There has also existed in popular belief the concept of white Witches and white witchcraft, which is strictly benevolent. Many neopagan Witches strongly identify with this concept, and profess ethical codes that prevent them from performing magic on a person without their request.

Where belief in malicious magic practices exists, such practitioners are typically forbidden by law as well as hated and feared by the general populace, while beneficial magic is tolerated or even accepted wholesale by the people – even if the orthodox establishment objects to it.

Strictly speaking, "necromancy" is the practice of conjuring the spirits of the dead for divination or prophecy - although the term has also been applied to raising the dead for other purposes. The Biblical Witch of Endor is supposed to have performed it (1 Sam. 28), and it is among the witchcraft practices condemned by Ælfric of Eynsham:

"Witches still go to cross-roads and to heathen burials with their delusive magic and call to the devil; and he comes to them in the likeness of the man that is buried there, as if he arise from death."

During the 20th century interest in witchcraft in English-speaking and European countries began to increase, inspired particularly by Margaret Murray's theory of a pan-European witch-cult originally published in 1921, since discredited by further careful historical research. Interest was intensified, however, by Gerald Gardner's claim in 1954 in witchcraft Today that a form of witchcraft still existed in England. The truth of Gardner's claim is now disputed too, with different historians offering evidence for or against the religion's existence prior to Gardner.

The Wicca that Gardner initially taught was a witchcraft religion having a lot in common with Margaret Murray's hypothetically posited cult of the 1920s. Indeed Murray wrote an introduction to Gardner's witchcraft Today, in effect putting her stamp of approval on it. Wicca is now practised as a religion of an initiatory secret society nature with positive ethical principles, organised into autonomous covens and led by a High Priesthood. There is also a large "Eclectic Wiccan" movement of individuals and groups who share key Wiccan beliefs but have no initiatory connection or affiliation with traditional Wicca. Wiccan writings and ritual show borrowings from a number of sources including 19th and 20th century ceremonial magic, the medieval grimoire known as the Key of Solomon, Aleister Crowley's Ordo Templi Orientis and pre-Christian religions. Both men and women are equally termed "Witches." They practice a form of duotheistic universalism.

Since Gardner's death in 1964 the Wicca that he claimed he was initiated into has attracted many initiates, becoming the largest of the various witchcraft traditions in the Western world, and has influenced various occult movements and groups. In particular it has inspired a large movement of "sole practitioners", who are not initiated into the original lineage but live according to practices and beliefs that are in keeping with the original tenets of the religion, most notably the "Three Laws".

Especially in media aimed at children (such as fairy tales), Witches are often depicted as wicked old women with wrinkled skin and pointy hats, clothed in black or purple, with warts on their noses and sometimes long claw-like fingernails. Like the Three Witches from Macbeth, they are often portrayed as concocting potions in large cauldrons. Witches typically ride through the air on a broomstick as in the Harry Potter universe or in more modern spoof versions, a vacuum cleaner as in the Hocus Pocus universe. They are often accompanied by black cats. One of the most famous recent depictions is the Wicked Witch of the West, in L. Frank Baum's The Wonderful Wizard of Oz.

Stereo-typical witch hat Cauldron - another connotation attributed by popular culture

Witches may also be depicted as essentially good, as in Terry Pratchett's Discworld novels, or the television show Charmed. Following the movie The Craft, popular fictional depictions of witchcraft have increasingly drawn from Wiccan practices, portraying witchcraft as having a religious basis and Witches as humans of normal appearance.