What is a barcode?

A barcode is an optical machine-readable representation of data relating to the object to which it is attached. Originally barcodes represented data by varying the widths and spacings of parallel lines, and may be referred to as linear or one-dimensional (1D). Later they evolved into rectangles, dots, hexagons and other geometric patterns in two dimensions (2D). Although 2D systems use a variety of symbols, they are generally referred to as barcodes as well. Barcodes originally were scanned by special optical scanners called barcode readers. Later, scanners and interpretive software became available on devices including desktop printers and smartphones. (Information found at http://en.wikipedia.org/wiki/Barcode)


The first use of barcodes was to label railroad cars, but they were not commercially successful until they were used to automate supermarket checkout systems, a task for which they have become almost universal. Their use has spread to many other tasks that are generically referred to as Automatic Identification and Data Capture (AIDC). The very first scanning of the now ubiquitous Universal Product Code (UPC) barcode was on a pack of Wrigley Company chewing gum in June 1974. (Information found at http://en.wikipedia.org/wiki/Barcode)

Why barcodes exist

The main reason that barcodes exist is that machines have a hard time reading text. Although Optical Character Recognition (OCR) has come a long way, the wide variety of possible fonts, damage caused by scanning and faxing, variations in viewing angles, and many other factors, can make a string of characters more difficult to accurately decode than barcodes. The barcode standards impose strict guidelines on line widths, size, shape, encoding, error detection and correction, all with the specific intent of reducing reading errors.

With the availability of fast, accurate barcode reading and writing toolkits and software, it is has become almost easy to use barcodes to reliably transfer information. With some basic information about barcode technologies, you can determine how their use could streamline your workflows, which symbology best suits your specific needs, and how to maximize their reliability.

1D Barcodes

A 1D barcode is read horizontally, from left to right. This makes a 1D bar code different from a 2D barcode, which can store information both horizontally and vertically. The information stored on a 1D barcode is alphanumeric (letters and numbers) and might include information such as product numbers or an address.

2D Barcodes

A 2D barcode, also known as a two-dimensional barcode, is a graphical image that stores information both horizontally and vertically. As a result, 2D barcodes can store up to 7,089 characters; significantly greater storage than is possible with the 20-character capacity of a 1D barcode.