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Mediumship is the practice of purportedly mediating communication between spirits of the dead and living human beings. Practitioners are known as "mediums" or "spirit mediums". There are different types of mediumship or spirit channelling, including seánce tables, trance, and ouija.

Mediumship gained popularity during the nineteenth century, when ouija boards were used by the upper classes as a source of entertainment. Investigations during this period revealed widespread fraud—with some practitioners employing techniques used by stage magicians—and the practice began to lose credibility. Fraud is still rife in the medium/psychic industry, with cases of deception and trickery being discovered to this day.