A POS or point of sale is a device that is used to process transactions by retail customers. A cash register is a type of POS. The cash register has largely been replaced by electronic POS terminals that can be used to process credit cards and debit cards as well as cash.

A POS may be a physical device in a brick-and-mortar store or a checkout point in a web-based store.

The software for POS devices is growing increasingly elaborate, with features that allow retailers to monitor inventory and buying trends, track pricing accuracy, and collect marketing data.