UPDATE  POS is web application Software.

This is suitable for small and medium businesses/organization.

Simple User Interface
Products with taxes
Barcode and Label Printing page
Add customer without leaving POS Screen
Hold bills option to save it in open bills
Discount (now you can add different discount to each sale)
Edit Product Price, Quantity, Sale tax and discount from POS
Check today’s sales and load nay open bill without leaving POS Screen
Print or Email receipts
Barcode scanner/reader compatible