jinni, in Arabic mythology, a spirit inhabiting the earth but unseen by humans, capable of assuming various forms and exercising extraordinary powers. Belief in jinn was common in pre-Islamic Arabia, where they were thought to inspire poets and soothsayers. Their existence was affirmed in the Qurʾān, and they are conceptualized in Islam as creatures parallel to human beings who are capable of choosing between good and evil and must thus face eventual salvation or damnation. They are beings of smokeless flame by nature, in the same manner in which humans are said to be made of earth, and they cannot be seen by human beings.
Jinn, especially through their association with things unseen, have always been favourite figures in North African, Egyptian, Syrian, Persian, and Turkish folklore and are at the centre of an immense popular literature, appearing notably in The Thousand and One Nights. In India and Indonesia they have entered the local Muslim imagination by way of the Qurʾānic descriptions and Arabic literature.
In common folklore, jinn are capable of assuming human or animal form and are said to dwell in all conceivable inanimate objects—stones, trees, ruins—and underneath the earth, in the air, and in fire. They possess the bodily needs of human beings and can even be killed, but they are free from all physical restraints. Jinn delight in punishing humans for any harm done to them, intentionally or unintentionally, and are said to be responsible for many diseases and all kinds of accidents. However, those human beings knowing the proper magical procedure can exploit the jinn to their advantage.
Ghūl (treacherous spirits of changing shape; ghouls), ʿifrīt (diabolical, evil spirits), and siʿlā (treacherous spirits of invariable form) constitute classes of jinn.