Selective racking is a popular racking type for bulk storage of materials and goods. Appropriate for both pallets and boxes, selective racking gives warehouse operators the ability to access goods where and when they need them. Bays are constructed in such a way where retrievers have direct access to the pallet they need without having to move others out of the way. Most common warehouses have single rows against the walls and double rows in the middle of the warehouse, creating aisles in between, so people, forklifts or AGVs can move about to retrieve pallets. It is the most common style of pallet racking today.