A warehouse is an industrial building used for storage. Not so many years ago, warehouses were places where men stacked bags and boxes by hand. Such buildings still exist, but many modem warehouses are far different. Today's warehouse might contain automatic cranes serving racks 25m (85ft) high. Or it might include a mix of multi-level conveyors and wireguided turret trucks in aisles just 2m (6ft) wide. Even the term warehouse has become dated in some circles. Many industrial engineers speak instead of 11materials-handling systems" and 11distribution centres".