Plaster is a building material used for the protective or decorative coating of walls and ceilings and for moulding and casting decorative elements.^[1] In English, "plaster" usually means a material used for the interiors of buildings, while "render" commonly refers to external applications.^[2] Another imprecise term used for the material is stucco, which is also often used for plasterwork that is worked in some way to produce relief decoration, rather than flat surfaces.