The printed code used for recognition by a barcode scanner (barcode reader). The "bar" in barcode comes from the ubiquitous, one-dimensional (1D) UPC barcode found on countless product packages. Several two-dimensional (2D) barcodes are also in wide use, but they are not as bar-like as the UPC. The 2D codes are scanned horizontally and vertically and hold considerably more data. All the 2D examples below contain the same data: the URL for www.computerlanguage.com. See barcode scanner, mobile tagging, point of sale and AIM. Contrast with RFID.
One-dimensional (1D) UPC barcodes are used on millions of consumer items as well as shipping containers. For details, see UPC
2D QR Code
Widely used to mark products as well as identify establishments, QR codes are recognizable by their four squares with dots in the middle. For details, see QR code
Symbol Technologies' PDF417 is a general-purpose barcode that is recognizable by patterns of vertical lines on each side. For details, see PDF417
The DataMatrix code is used to mark small parts and holds up to 2,355 alphanumeric and 3,116 numeric characters. It is recognizable by its border with two solid lines and two alternating lines.
The MaxiCode uses hexagonal symbols and is recognizable by its center bull's eye. Used for high-speed sorting, it holds up to 93 alphanumeric and 138 numeric characters. For more data, MaxiCodes can be chained together. (Image courtesy of AIM, Warrendale, PA, www.aimglobal.org)
Designed for mobile tagging, this system from Switzerland accepts company logos. Recognizable by its honeycomb-like cells, BeeTaggs are also used for exchanging business card data. For more information, visit www.beetagg.com. See mobile tagging
2D Microsoft Tag
Also developed for mobile tagging, Microsoft's system uses color. Another form of the tag allows a company logo to occupy the background. For details, see Microsoft Tag