Relief is a sculptural technique where the sculpted elements remain attached to a solid background of the same material. The term relief is from the Latin verb relevo, to raise. To create a sculpture in relief is to give the impression that the sculpted material has been raised above the background plane. What is actually performed when a relief is cut in from a flat surface of stone (relief sculpture) or wood (relief carving) is a lowering of the field, leaving the unsculpted parts seemingly raised. The technique involves considerable chiselling away of the background, which is a time-consuming exercise. On the other hand, a relief saves forming the rear of a subject, and is less fragile and more securely fixed than a sculpture in the round, especially one of a standing figure where the ankles are a potential weak point, especially in stone. In other materials such as metal, clay, plaster stucco, ceramics or papier-mâché the form can be just added to or raised up from the background, and monumental bronze reliefs are made by casting.
There are different degrees of relief depending on the degree of projection of the sculpted form from the field, for which the Italian and French terms are still sometimes used in English. The full range includes high relief (alto-rilievo, haut-relief), where more than 50% of the depth is shown and there may be undercut areas, mid-relief (mezzo-rilievo), low-relief (basso-rilievo, or French: bas-relief), and shallow-relief or rilievo schiacciato, where the plane is only very slightly lower than the sculpted elements. There is also sunk relief, which was mainly restricted to Ancient Egypt (see below). However, the distinction between high relief and low relief is the clearest and most important, and these two are generally the only terms used to discuss most work.