A generic term for a thin, rigid material made of wood fiber molded under heat and pressure. Hardboard may be used as a painting surface when it is sealed and primed. It offers some advantages over traditional wood panel because does not swell or shrink with humidity changes and it is not attacked by wood-boring insects. Hardboard was commercially manufactured in England by 1893, and artists in Europe and North America were using it as a painting support in the late 1920s. See also: Masonite.