Witchcraft traditionally means the use of magic or supernatural powers to harm others. A practitioner is a witch. In medieval and early modern Europe, where the term originated, accused witches were usually women who were believed to have used malevolent magic against their own community, and often to have communed with evil beings. It was thought witchcraft could be thwarted by protective magic or counter-magic, which could be provided by cunning folk or folk healers. Suspected witches were also intimidated, banished, attacked or killed. Often they would be formally prosecuted and punished, if found guilty or simply believed to be guilty. European witch-hunts and witch trials in the early modern period led to tens of thousands of executions. In some regions, many of those accused of witchcraft were folk healers or midwives. European belief in witchcraft gradually dwindled during and after the Age of Enlightenment.

Contemporary cultures that believe in magic and the supernatural often believe in witchcraft. Anthropologists have applied the term "witchcraft" to similar beliefs and occult practices described by many non-European cultures, and cultures that have adopted the English language will often call these practices "witchcraft", as well. As with the cunning-folk in Europe, Indigenous communities that believe in the existence of witchcraft define witches as the opposite of their healers and medicine people, who are sought out for protection against witchcraft. Modern witch-hunting takes place in parts of Africa and Asia.

A theory that witchcraft was a survival of a European pagan religion (the witch-cult hypothesis) gained popularity in the early 20th century, but has been discredited. A newer theory is that the idea of "witchcraft" developed to explain strange misfortune, similar to ideas such as the evil eye.

In contemporary Western culture, most notably since the growth of Wicca from the 1950s, some modern pagans and followers of New Age belief systems may self-identify as "witches", and use the term "witchcraft" for their self-help, healing or divination rituals. Others avoid the term due to its negative connotations.