A shaman is a person who interacts with both the normal world and the world of spirits, usually acting as a sort of intermediary between the two. Shamans are common in many tribal cultures, although shamanism may also exist in other types of culture. The shaman is often responsible for both the physical and spiritual health of people, and may also be called upon to invoke spirits for aid, or to predict the future and interpret omens.

Central to the idea of the shaman is the concept of a focal point where the natural and supernatural worlds connect. This node is often viewed as the center of the world, and may be associated with an archetypal feature — such as the World Tree. A shaman crosses over from the natural world into the supernatural world, and often must overcome certain trials there to exert some power over the world of the spirits. When the shaman then returns to the natural world, they have been imbued with special powers or knowledge, which they can use either for good or ill.

The path a shaman takes varies widely, depending on the cultural context they come from. Many people have pointed out that generalizing all tribal belief systems to a single term — shaman — fails to take into consideration the diversity these paths may take. A shaman may use force to gain their power, literally trapping or enslaving spirits to do their bidding. A shaman may also use a more peaceful form of communion, becoming attuned with spirits in order to learn from them or request their help. Some shamans may view what they do as a literal movement, with their physical body accompanying them into the world of the spirits, while others may embark on their spirit journey while in a trance, using a form of astral projection to visit the spirit realm.

The powers a shaman possesses also depend on the cultural context, the skill of the shaman, and their level of knowledge. A shaman may be able to see into the future and the past, foretelling events and warning against certain courses of action. A shaman may be able to heal sicknesses, often thought to be brought about by malevolent spirits, or even to heal more pronounced physical wounds by calling upon the aid of benevolent spirits. A shaman may exert control over the weather, calling rain to water crops, or storms to punish enemies. A shaman may fly or teleport their body instantly, cause plants to grow or wither, make women fertile or barren, or exert total control over their body by stopping their heart, cutting themselves without bleeding, or holding burning hot coals in their hands.

The term is used in such a broad context that it covers many traditional healers or miracle workers in tribal societies. Any belief system that is predicated upon the idea of unseen spirits that interact constantly with our world — spirits that can be contacted or controlled by one with proper training and power — is essentially shamanistic. Unlike priests, shamans operate independently, perhaps learning their art from an old shaman or a spirit guide.