UPC, RFID, and QR Codes
There are three common technologies retailers use to identify and track individual product units in retail sales transactions, inventory management and distribution, or supply chain- UPC, RFID and QR codes. Most of these symbols are quite familiar as we see them on a daily basis.
The Universal Product Code (UPC) is a barcode symbology that is widely used in the United States, Canada, United Kingdom, Australia, New Zealand, in Europe and other countries for tracking trade items in stores.
Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. The tags contain electronically-stored information. No line-of-sight is required to receive information from RFID which makes it better suited for inventory flowing through a warehouse conveyor system, for example.
A quick response code (QR code) is a matrix barcode made up of dots. Because it is two-dimensional, it can hold substantially more data than one-dimensional barcodes, such as UPC. It can be read by a QR scanner or by a smartphone with a camera.
This YouTube video does a fairly good job providing some background information on this technology. It discusses the origin of bar codes, describes how they work, and helps us understand the evolution to QR codes.