According to the way of loading of the shelves: cantilever shelves, cabinet-type shelves, shelf-plate shelves. According to the structure of the shelves of the combination of removable shelves, fixed-type shelves. Which is divided into unit-type shelves, general-type shelves, mobile shelves, through-type shelves. According to the shelf height: lower shelf: Height below 5 meters, middle shelf: height in 5-15 meters, high shelf: height above 15 meters. By the weight of the shelf: heavy shelves: The shelf weight of each layer of 500 kg or more; medium shelf: Each shelf load 150-500 kg, light shelf: each shelf weight of 150 kg below.