The Ouija, also known as a Oujia board, spirit board, talking board, or witch board, is a flat board marked with the letters of the Latin alphabet, the numbers 0–9, the words "yes", "no", and occasionally "hello" and "goodbye", along with various symbols and graphics. It uses a planchette as a movable indicator to spell out messages during a séance. Participants place their fingers on the planchette, and it is moved about the board to spell out words. The name "Ouija" is a trademark of Hasbro, but is often used generically to refer to any talking board.

A planchette, from the French for "little plank", is a small, usually heart-shaped flat piece of wood equipped with two wheeled casters and a pencil-holding aperture pointing downwards, used to facilitate automatic writing. The use of planchettes to produce mysterious written messages gave rise to the belief that the devices foster communication with spirits as a form of mediumship. The devices were popular in séances during the Victorian era, before their eventual evolution into the simpler, non-writing pointing devices for ouija boards that eclipsed the popularity of their original form. Scientists explain the motion is due to the ideomotor effect, but paranormal advocates believe the planchette is moved by the presence of spirits or some form of subtle energy.