Stores can be on-line to a central server or they can operate with their own copies of programs and data, with regular, e.g. hourly, information exchange between a central server and stores.
If the stores are on-line, then the consolidated data is always up-to-date. Otherwise, information from other locations is bought up-to-date with each information exchange.
Head office functions can include comprehensive merchandising and performance management, inventory control, Replenishment management, accounts payable, accounts receivable and general ledger including financial management reporting. Any of these functions can be available in the stores also if required.