'Storage', in Ordinary, is the stocking of goods, household or commercial. Self storage is an industry in which storage space like rooms, lockers, containers, and/or outdoor space, is rented to tenants in which they can store and access their goods. Self storage facilities lease space to individuals usually for storing household goods and the rented spaces are secured by the tenant's own lock and key.
A warehouse, on the other hand, is a commercial building for storage of goods. Warehouses are used by manufacturers, importers, exporters, wholesalers, transport businesses, customs, etc. They are usually large plain buildings in industrial areas of cities and towns. They have loading docks to load and unload goods from trucks. Sometimes warehouses load and unload goods directly from railways, airports, or seaports.