Shamanism itself is not a religion, but a practice found within indigenous cultures around the world. The word itself comes from the Tungus people of Siberia. In modern usage, it has come to refer to any medicine man or woman within the indigenous culture who practices spirit journeys via an altered state of consciousness. Many forms of religion contained shamanistic practitioners within them, including Christianity, Judaism, Islam or Buddhism. It is most well-known in Eastern European, South Pacific, South American and Native American cultures.

In some cultures shamans performed the roles of doctors/healers, teachers, artists, magicians and seers. But all cultures that had shamans shared one belief, that the shaman worked to bridge the known world and the unknown world. Moving beyond the physical world, the shaman seeks spirit energies for assistance, healing and knowledge from the ancestors and the gods.

Shamans believe that parts of the soul are able to travel, leaving the body and passing through time and space. A certain amount of this happens to everyone via the experience of dreaming. A shaman undertakes these journeys intentionally for a purpose. The soul is also believe to sometimes lose parts when extreme traumas happen, to protect the remaining energies and the body. Sometimes the shamanic journey is to retrieve these lost parts, returning them to the person so that they can again have their whole energies.

Spirit guides often work in conjunction with the shaman. Specific spirits may be involved and they may be human or animal in form. Totem animals are present in nearly every form of shamanism. Which specific animals were considered the most powerful or revered varied from culture to culture, most often connected closely to how the tribal group lived.

In many cultures, there are stories of knowledge passed from the gods or from animals to humans. Healing knowledge, use of plants, farming and cultivation and many more skills were developed by tribal peoples without any scientific basis for their uses, but these people knew their methods and techniques worked. Most often the shaman was the recipient of this knowledge and passed it to the rest of the group.

In addition to dream work, Shamans used altered states of consciousness, trance or ecstatic states, to leave the body and contact the spirit energies. Prolonged drumming or rattling, singing or dancing are all ways the shaman entered these altered states, along with the use of sacred plants, most often hallucinogens. Sometimes these were elaborate rituals that engaged the entire tribe, other journeys were done privately.

The role of the shaman was extremely varied and modern scholars of shamanism can find themselves studying a variety of disciplines to gather information: history of religions, anthropology, mythology, folklore, ethnobotany, and psychology or psychiatry.