A POS machine is a point of sales machine that includes a debit and credit card reader for accepting payments. It also provides a receipt for the transactions and maintains a sales history for accountability. A modern retail POS machine goes way beyond the basic functions of an old-school cash register, even when it looks like one on the outside. On an ancestral cash register, you needed to enter the price of each product manually; now, however, the prices are pre-programmed into the system and are read from a barcode scanner. That cuts down substantially on the potential for mistakes, and it also improves the accuracy of your sales reports. The POS terminal can be set up to track and record your sales of products and services in just about any way that's meaningful to you, and usually, this ties directly into your accounting software so that information is always at your fingertips.