The steel plate is divided according to the thickness, the thin steel plate < 4 mm (the thinnest 0.2 mm), the thick steel plate 4~60 mm, the extra thick steel plate 60~115 mm. The steel plate is divided into rolling, hot rolling and cold rolling. The width of the sheet is 500~1500 mm; The width of the thickness is 600~3000 mm. According to the kinds of steel, there are ordinary steel, high quality steel, alloy steel, spring steel, stainless steel, tool steel, heat resistant steel, bearing steel, silicon steel and industrial pure iron sheet. According to the professional use, there are oil drum board, enamel board, bulletproof board, etc.; According to the surface coating, there are galvanized sheet, tin plate, lead plate, plastic composite steel plate, etc.