Abstract: A computer system for entering, processing and recording sales of items is provided, which is especially suitable for use in retail sales, particularly quick service restaurants. The system includes a plurality of programmable POS registers for entering and tabulating customer orders, an off-line processor for programming the programmable POS registers, shared memory for recording data entered and tabulated by the programmable POS registers, and a communication structure for networking a plurality of programmable POS registers, the off-line processor and the shared memory. In one embodiment, the system includes an access control system for enabling access to the POS registers, the off-line processor or the shared memory if operation of those are authorized.