The control of subsidiaries may be accomplished through the creation of a separate corporation to handle a distinct phase of the company's business, or through the purchase of interests in companies previously existing, the main corporation being in this case the holding company. The use of subsidiary corporations is becoming more and more extensive. A certain manufacturing corporation, for instance, has one operating company, one selling company, one purchasing company, one company owning a short railroad, one real estate company to buy land and erect buildings, and another company to operate these buildings. The United Cigar Stores Company also has a distinct corporation for the handling of its real estate operations.