Bar Code Technology

Since their invention more than 50 years ago, bar codes have been enablers for accurate data capture, the rapid movement of goods, and all types of automation. Whether at the Point-of-Sale, in a hospital, or in a manufacturing environment these little black and white images deliver incredible value.

There are many different bar code symbologies, or languages. Each symbology has its own rules for encoding characters (e.g., letter, number, punctuation), printing, decoding requirements, and error checking.

Bar code symbologies differ both in the way they represent data and in the type of data they can encode: some encode numbers; others encode numbers, letters, and a few punctuation characters; still others offer encodation of the 128 or 256 ASCII character sets. Recently unveiled symbologies include options to encode characters in any language as well as specialized data types.

Bar codes in common use are covered by international standards. International standards also cover print quality measurements and equipment.

Bar code technology standards define:

• Rules for representing data in an optically readable format,
• Rules and techniques for printing or marking,
• Reading and decoding techniques, and
• Rules for measuring the quality of printed/marked symbols