Glass is an amorphous inorganic non-metallic material, generally made up of a variety of inorganic minerals (such as quartz sand, borax, boric acid, barite, barium carbonate, limestone, feldspar, soda ash, etc.) as the main raw material, and a small amount of auxiliary materials are added. of. Its main components are silica and other oxides. The chemical composition of ordinary glass is Na2SiO3, CaSiO3, SiO2 or Na2O·CaO·6SiO2, etc. The main component is a silicate double salt, which is an amorphous solid with a random structure. Widely used in buildings, used to separate light from the wind, is a mixture. There are also colored glass in which a certain metal oxide or salt is mixed to exhibit color, and tempered glass obtained by physical or chemical methods. Sometimes some transparent plastics (such as polymethyl methacrylate) are also called plexiglass.