Lamination is the technique of manufacturing a material in multiple layers, so that the composite material achieves improved strength, stability, sound insulation, appearance or other properties from the use of differing materials. A laminate is a permanently assembled object by heat, pressure, welding, or adhesives. The decorative arts are arts or crafts concerned with the design and manufacture of beautiful objects that are also functional. It includes interior design, but not usually architecture. The decorative arts are often categorized in opposition to the "fine arts", namely, painting, drawing, photography, and large-scale sculpture, which generally have no function other than to be seen.