Medium-density fiberboard (MDF) is an engineered wood panel made by breaking down hardwood or softwood residuals into wood fibers, MDF is generally denser than plywood. It is made up of separated fibers, but can be used as a building material similar in application to plywood. It is stronger, and denser, than particle board. The name derives from the distinction in densities of fiberboard. Large-scale production of MDF began in the 1980s, in both North America and Europe.