Point of sale

This system was the first commercial use of client-server technology, peer-to-peer communications, local area network (LAN) simultaneous backup, and remote initialization.

Each station in the restaurant had its own device which displayed the entire order for a customer — for example, [2] Vanilla Shake, [1] Large Fries, [3] BigMac — using numeric keys and a button for every menu item.

In 1986, Gene Mosher introduced the first graphical point of sale software[7] featuring a touchscreen interface under the ViewTouch[8] trademark on the 16-bit Atari 520ST color computer.

[9] It featured a color touchscreen widget-driven interface that allowed configuration of widgets representing menu items without low level programming.

[10] The ViewTouch point of sale software was first demonstrated in public at Fall Comdex, 1986,[11] in Las Vegas Nevada to large crowds visiting the Atari Computer booth.

In 1986, IBM introduced its 468x series of POS equipment based on Digital Research's Concurrent DOS 286 and FlexOS 1.xx, a modular real-time multi-tasking multi-user operating system.

Although experienced employees work more quickly with mechanically keyed entry,[12] some systems favoured adopting GUI technology for ease of learning or for ergonomic factors.

[13] The key requirements that must be met by modern POS systems include high and consistent operating speed, reliability, ease of use, remote supportability, low cost, and rich functionality.

Many POS systems are software suites that include sale, inventory, stock counting, vendor ordering, customer loyalty and reporting modules.

Comprehensive analysis performed by a POS machine may need to process several qualities about a single product, like selling price, balance, average cost, quantity sold, description and department.

Currently POS systems are also used in goods and property leasing businesses, equipment repair shops, healthcare management, ticketing offices such as cinemas and sports facilities and many other operations where capabilities such as the following are required: processing monetary transactions, allocation and scheduling of facilities, keeping record and scheduling services rendered to customers, tracking of goods and processes (repair or manufacture), invoicing and tracking of debts and outstanding payments.

This puts high demand not just on software coding but also designing the whole system covering how individual stations and the network work together, and special consideration for the performance capability and usage of databases.

[15] With regard to databases, POS systems are very demanding on their performance because of numerous submissions and retrievals of data - required for correct sequencing the receipt number, checking various discounts, membership, calculating subtotal, so forth - just to process a single sale transaction.

Enterprise database Microsoft SQL Server, for example, has been known to freeze up (including the OS) entirely for many minutes under such conditions showing a "Timeout Expired" error message.

POS system accuracy is demanding, given that monetary transactions are involved continuously not only via the sale window but also at the back end through the receiving and inputting of goods into the inventory.

This user interface is highly critical when compared to those in other software packages such as word editors or spreadsheet programs where the speed of navigation is not so crucial for business performance.

The faster a sale is completed the shorter the queue time which improves customer satisfaction, the less space it takes, which benefits shoppers and staff.

The advent of cloud computing has given birth to the possibility of electronic point of sale (EPOS) systems[16] to be deployed as software as a service, which can be accessed directly from the Internet using a web browser.

It can also mean that the system software and cloud server must be capable of generating reports such as analytics of sale against inventory for both a single and multiple outlets that are interlinked for administration by the headquarters of the business operation.

For such contingency, a more innovative though highly complex approach for the developer is to have a trimmed down version of the POS system installed on the cashier computer at the outlet.

The POS interface at a retail establishment varies greatly depending on the industry and owner of the retailer, but usually includes a cash register (typically a specialized x86-based computer running Windows Embedded or Linux), a method for employee input, cash drawer, receipt printer, barcode scanners (which may incorporate a scale), and an interface for processing Card payments and Processing Customer Information (a Payment Terminal).

In the past, most IBM systems used a primarily keyboard-based interface, and NCR previously used side-keys on their displays before touchscreens were widely available, similar to their ATM products.

POS software can also allow for functions such as pre-planned promotional sales, manufacturer coupon validation, foreign currency handling and multiple payment types.

Self-service grocery stores such as Piggly Wiggly, beginning in 1916, allowed customers to fetch their own items and pass the point of sale enroute to the exit.

With the development of the mobile technology, Cloud-based POS systems are also put forward to increase the efficiency of some restaurants, integrated with some latest software services such as scan QR code to order by customers themselves.

On the software and hardware side each tablet on a customer table has to be networked to the cashier POS station and the kitchen computer so that both are continually updated on orders placed.

Therefore, from 1 January 2018, all retail businesses in France are required to record customer payments using certified secure accounting software or cash register systems.

The ability of a POS system to void a closed sale receipt for refund purpose without needing a password from an authorized superior also represents a security loophole.

This is one effective way to alert the company to any suspicious activity - such as a high number of cancelled sales by a certain cashier - that may be occurring, and to take monitoring action.

To further deter employee theft, the sales counter should also be equipped with a closed-circuit television camera pointed at the POS system to monitor and record all activities.