What is a POS system? A retail guide
Understand checkout equipment, payments and stock records, with clear examples of what a shop needs before buying.
Last updated October 31, 2026
A point-of-sale system combines the software and equipment a business uses to record a sale and take payment. In a shop, it connects the products in a customer's basket with prices, a payment method and a receipt. Depending on the system and plan, it can keep stock records and sales reports too.
The useful question is what happens after someone pays. Can you see which product sold, at which location, and whether the stock balance changed? Those details determine how much work remains at the end of a shift.
How does a POS system work?
A typical sale follows a short sequence:
- The cashier scans a product or finds it in the catalog.
- The software adds the item, quantity and price to the basket.
- Any permitted discount and configured tax are applied.
- The customer chooses a payment method, such as cash or card.
- The cashier checks the payment result and completes the sale.
- The system records the transaction and offers a receipt.
When stock tracking is connected and configured, the sale changes the relevant product balance. The exact timing and treatment of unpaid or canceled orders depend on the software. Ask a provider to show the transaction and stock record side by side.
For a concrete example, Shopify's POS documentation describes creating a cart, accepting payment and syncing orders and inventory with the Shopify admin. That is one provider's workflow, not a promise that every checkout works the same way.
POS hardware and software
Software holds the product catalog and controls checkout. Hardware gives staff and customers a way to use it. A small counter might need a tablet, card reader and receipt printer; another business might need a fixed terminal and scanner.
| Part | What to check before buying |
|---|---|
| Checkout device | Screen size, supported operating system and how staff sign in |
| Card reader | Supported payment methods, country and processor |
| Barcode scanner | Whether it reads your actual product labels |
| Receipt printer | Connection type, paper and compatibility |
| Cash drawer | How it opens and who can open it without a sale |
Buy against the provider's supported equipment list. A USB socket or Bluetooth connection alone does not prove that two devices will work together.
POS system vs card terminal
A standalone card terminal processes a payment amount. It may not know which items the customer bought. If staff type a total into a separate reader, check how they confirm that the payment matches the basket and what happens after a decline.
An integrated reader receives the amount from checkout and returns the payment result. Some devices combine both functions in one unit. Judge the workflow rather than the shape of the machine.
Cash register vs POS
A basic cash register can record amounts and hold cash. A product-based checkout can connect those amounts to individual items, people and locations. The difference matters when you need to explain a stock discrepancy or identify which sizes sold.
A register can still suit a simple counter. Moving to more software makes sense when the information it captures removes a recurring problem, not merely because it looks newer.
Types of POS systems
Common setups include a fixed counter terminal, a tablet with separate accessories and a handheld device for serving customers away from the counter. Cloud services commonly provide remote access to administration and reports. Other systems keep more of their operation on local equipment.
These categories overlap. A cloud service can have some offline functions, and a handheld device can use the same catalog as a fixed counter. Compare where data is stored, which features require a connection and how you recover after equipment fails.
What does a POS system track?
Start with transaction references, dates, item quantities, prices, discounts, payment methods and refunds. Then check whether the plan includes stock by location, staff activity and the reports you need. Customer records and loyalty programs are additional capabilities, not requirements for every sale.
Keep the difference between recorded activity and physical reality in mind. A checkout cannot discover a damaged item on a shelf unless someone records it. Read the guide to connecting checkout and stock records before relying on the displayed quantity.
POS reports for retailers
Three useful starting views are sales by product, payment totals for a shift and returns with their original references. Product sales help with replenishment. Payment totals help with closing. Return records help explain why money and stock moved in different directions.
For cash, compare the recorded activity with a physical count using a consistent process. The free till reconciliation tool helps lay out that count; it does not connect to a payment processor or verify a sale.
Frequently asked questions
Can a POS system work offline?
Sometimes, but offline checkout and offline card acceptance are separate capabilities. Ask which devices, payment methods and time limits apply. Square's offline-payment guidance explains that offline transactions are uploaded later and that sellers bear the risk of expired, declined or disputed payments. A stored transaction is not the same as a confirmed payment.
Do small shops need a POS system?
The decision depends on the work you need it to do. List recurring problems, such as retyping totals, missing product-level sales or slow returns, then test whether a system resolves them. Use the selection checklist to compare the same tasks across providers.
Does headoffis take payments at the counter?
No. headoffis is a workspace for people, tasks, inventory and retail operations. It can record sales and review supported sales CSV imports, but it is not a card terminal or a checkout payment processor. Keep the payment record in your POS and use a defined process for the operational work around it.