A Point of Sale (POS) system is the software a shop uses to ring up sales, take payment, print receipts and keep stock accurate in real time. Building one in PHP and MySQL is a fantastic way to learn transactional programming, because every sale has to update several tables consistently — or not at all.
What the system handles
- Cash, cheque and credit sales
- Receipt generation
- Stock deduction as items are sold
- Customer and supplier records and ledgers
Reports it can generate
- Individual, daily, weekly, monthly and yearly sales
- Inventory and stock-remaining reports
- Collectibles and supplier reports
- Per-customer ledgers
The key concept: transactions
When a cashier completes a sale, the app must insert the sale, insert each line item, and reduce stock for each product. If any step fails, none should be saved. That’s what database transactions (BEGIN / COMMIT / ROLLBACK) are for, and a POS is the clearest possible example of why they matter.
Technology stack
Plain PHP with MySQL is ideal here — it keeps the focus on the data logic. Add a little JavaScript for barcode entry and live totals, and Bootstrap for a clean cashier screen.
What you’ll learn
Atomic transactions, accurate stock accounting, receipt formatting, and how to design reports that aggregate the same sales data by day, week, month and year.
Frequently asked questions
How do I handle barcode scanners?
Most scanners act like a keyboard — they “type” the code and press Enter. Capture that into your product-lookup field and no special drivers are needed.
Can it support multiple cashiers?
Yes — add user accounts and stamp every sale with the cashier ID so each session and shift can be reconciled.
A note on using this project
This guide is written to help students and developers understand how a PHP/MySQL application like this is designed and built. Treat any sample code as a learning reference: read it, run it locally, and adapt it to your own requirements rather than shipping it unchanged. If you reuse third-party components, check their licences first.