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Barcode Glossary [A-J]

ABC Symbol — The American Blood Commission (ABC) developed this symbol as a bar code standard for automated systems in the blood service community. The particular symbology used for the ABC symbol is Codabar.

AIM International (AIMI) is a global affiliation of trade associations whose member companies are involved with application of automatic identification technology. For more information access

AIMI MISSION: The mission of AIM International, Inc., is to grow the worldwide market for Automatic Identification and Data Collection (AIDC) products and services. We accomplish this through concerted action to set international standards, increase global awareness of AIDC solutions and identify and educate current and potential new users on the effective application of the technology.

ANSI — American National Standards Institute has served in its capacity as administrator and coordinator of the United States private sector voluntary standardization system for 78 years. Founded in 1918 by five engineering societies and three government agencies, the Institute remains a private, nonprofit membership organization supported by a diverse constituency of private and public sector organizations. For more information access

Aperture Size — The dimension of the opening through which the scanning beam passes. Normally used in conjunction with a wand (pen) type bar code scanning device. The aperture size will determine the bar code density which may be read with the scanning device.

ASCII — The character set and code described in American National Standard Code for Information Interchange between data processing systems, communication systems and associated equipment. The ASCII set consists of both control and printing characters.

Aspect Ratio — The numeric ratio of the bar’s height to the symbol’s length.

Background — The area surrounding a printed symbol, including the spaces and quiet zones. Also referred to as the Substrate.

Bar Code Character — A group of bars and spaces that represent an individual character (alpha, numeric or other ASCII character).

Bar Code Density — A measure of the number of characters which may be printed per lineal inch. This measure normally does not include the space required for the “Quiet Zone“.

Bearer Bars — A minimum of two parallel bars running the length of the top and bottom edge of a bar code. Bearer bars, if used, reduce the probability of a misread when a skewed scanning beam enters and/or leaves the symbol through the top or bottom.

Bi-Directional — Characteristic of most bar code symbologies which permits scanning of the bar code symbol in either the left-to-right or right-to-left direction.

Character Set — The set of characters permitted within a particular bar code symbology type.

Check Character — A character used to check the integrity of the preceding bar code symbol. A check character is normally found at the end of the data encoded within the bar code.

Clear Area — The area which precedes the first printed bar of the start character, and follows the last printed bar of the stop character. This area should be free from any printing, and should be of the same color and reflectance as the background of bar code symbol. The clear area should be ten times the width of the narrowest element in the bar code, or 0.25 inch minimum. Clear Area is also known as Quiet Zone.

Code 39 — An alphanumeric bar code that can encode decimal numbers, the upper case alphabet, and the following special symbols: _ . * $ / % + Also see Extended Code 39.

Codabar — A01234B.

Codabar is a discrete, numeric code with special characters and four different start/stop characters. Allowable data characters are (0 – 9), special characters (- $ : / . + ), and start-stop characters (A, B, C, D).

Code 128 is a continuous, multilevel, full ASCII code. There are three types of code 128 encoding. Type A provides the character set of all upper case alphanumeric characters plus all of the ASCII control characters. Type B provides the character set of all upper and lower case alphanumeric characters. Type C provides increased density for numeric encoding with double density numeric characters for all number pairs from 00 to 99.

Code 11 — A numeric, high density code.

Code 93 — A continuous, multilevel, full ASCII bar code.

Color Scheme — Scanners read bar codes by using red light to recognize the contrast between the bars and spaces of the symbol. Colors that will scan effectively need to be chosen. Black bars against a white background are the safest choice, but other combinations will also work. Quiet Zone: The margins around the bar codes are vital, they enable the scanner to identify the beginning and the end of the bar code.

Data Identifier — A character (or set of characters) that uniquely defines the specific use of the data encoded in the bar code symbol following the data identifier. Also known as a Flag Character.

Decoder — An electronic device which translates the electrical signals from a scanner into computer compatible data. The decoder performs checks on the electronic signal to validate it, and processes the signal through a decode algorithm designed to detect errors in the signal. The output of the decoder may drive a keyboard input to a terminal (seeKeyboard Wedge Decoder) or may interface with a communications port on a computer (see Serial Decoder).

Demand Printer — A printer capable of creating individual documents one at a time, as needed.

Dot Size (Printer) — The size of the printed dot on a substrate in a matrix or line to form characters. Minimum dot size is determined by the size of the thermal element of the print head being used by the thermal printer. Dot size determines the X dimension. The X dimension is always a simple multiple of the dot size.

Dot Size (Scanner) — The diameter of the beam of light projected by the scanner used to read a bar code symbol. The scanner dot size should be no larger than the X dimension of the bar code symbol.

EAN is an association which manages a world-wide system that allows the identification and communication of products, services, utilities, transport units and locations. It develops and maintains coding standards for all users, and has the aim of developing a global standard with the objective of providing a common language for international trade.

EAN International is a voluntary, not for profit International standards association, established to meet the communication needs of its users. EAN International was founded in 1977, as a result of the initiative of European manufacturers and distributors and has expanded to cover the world. The organization has a membership of 79 Numbering Organizations covering 86 countries. The EAN/UCC system is used by more than 600, 000 companies world-wide. For more information access

EAN Bar Code (European Article Number) — The international standard or system for applying unique article numbers and bar codes to products. The EAN bar code is a numeric only code, generally encoding 13 digits (known as EAN-13), though in specific circumstances shorter codes (EAN-8) and supplementary codes are used. The North American equivalent (now technically a subset of the EAN system) is the Universal Product Code (UPC).

Extended Code 39 — The full 128 character ASCII character set can be encoded by pairing Code 39 characters. Enabling Extended Code 39 causes the following characters to be output for each character pair.

FACT (Federation of Automated Coding Technology) — A bureau of AIM consisting of organizations that use and promote automatic identification among their members.

Flat Bed Scanner — A fixed scanner (used at supermarket checkouts) which can read bar code symbols at any angle in a plane parallel to or near parallel to the scanner window. Flat bed scanners are typically capable of reading bar code symbols from many different orientations. The term “Omni-Directional” scanning is referred to with this type of scanner.

Guard Bars — The auxiliary characters at both ends and center of EAN and UPC bar code symbols which provide reference points for scanning. In most cases the bars of these auxiliary characters are elongated. The guard bar function as start/stop characters; for omni-directional scanning the center guard bar (where present) acts as a stop character and the outer guard bars act as two separate start characters. There are no center guard bars on UPC-E symbols (and other less common architectures).

Human Readable — The text equivalent of the encoded information within the bar code symbol, normally printed below or above the bar code symbol, for convenience or confirmation of encoded data by humans.

Interleaved 2 of 5 code is a numeric only bar code. Due to the interleaving of the characters, the number of characters in an Interleaved 2 of 5 message must be even. The check character, if used, must be included in the character count Especially adapted to the poor quality of packaging materials frequently used for trade items (corrugated cardboard), it is designed to be read by a fixed or portable bi-directional scanner.

Inter-Character Space — The space between two adjacent bar code characters in a discrete code. Also called the Inter-Character Gap.

ISO (International Organization for Standardization) — is a worldwide federation of national standards bodies from some 100 countries, one from each country. ISO is a non-governmental organization established in 1947. The mission of ISO is to promote the development of standardization and related activities in the world with a view to facilitating the international exchange of goods and services, and to developing cooperation in the spheres of intellectual, scientific, technological and economic activity. For more information access