A three-part work of art whose panels bear a relationship to each other. It is usually a painting, meant for placement on an altar, with three hinged panels that fold together. Usually the middle panel has the primary theme, with side panels being supplementary. Often the Triptych is set on a base or platform called a Predella, which often has decoration corresponding to the Triptych. Altarpiece Triptychs were very common in Byzantine and western churches during the Medieval and Renaissance periods, and some modern artists such as Max Beckmann continue the tradition. Source: Ralph Mayer, "A Dictionary of Art Terms and Techniques"<br><br> A painting which consists of one center panel, with two paintings attached on either side by means of hinges or other means, as "wings."