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 http://www.ansi.org
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.
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
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.
Characteristic of most bar code symbologies which permits scanning of
the bar code symbol in either the left-to-right or right-to-left
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.
Code 39 -
An alphanumeric bar code that can encode decimal numbers, the upper
case alphabet, and the following special symbols: _ . * $ / % + .
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 ).
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.
- 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 or may interface with a
communications port on a computer .
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.
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
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.
of Automated Coding Technology) - A bureau of AIM consisting of
organizations that use and promote automatic identification among their
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.
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
Ladder Code -
A bar code printed in a vertical position such that the bars can be
thought of as rungs on a ladder. Contrast with Picket Fence.
applications for Marking And Reading Symbols) - A Department of Defense
program intended manage inventory by placing Code 39 bar code symbols
on all items sold to the Federal Government.
Manufacturer Identification Number -
The Manufacturer Identification Number is a six digit number assigned
to a manufacturer by the UCC (Uniform Code Council). This number is
found on the left side of the U.P.C. number. The number is composed of a
number system character and a five digit manufacturer's code.
Matrix Symbols -
A symbol which appears as a checker board; they are most likely square
in shape, and contain some form of unique "finder pattern," which
distinguishes them from others and provides a decoding reference for
One thousandth of an inch (0.001 inch), or approximately 0.0254
millimeter. Commonly used to refer to the width of bar code elements,
for example, 0.013 inch would be expressed as 13 mils.
Minimum Reflectivity Difference -
A white space will reflect more light than a black bar. The minimum
reflectivity difference is the variance between the least amount of
light reflected by the narrowest white space, and the most amount of
light reflected by the widest black bar. Minimum reflectivity difference
is one measure of the read-ability of the bar code symbol.
The situation which occurs when a bar code reading device detects a bar
code symbol incorrectly (different than intended). A mis-read may be
due to a defective symbol, to a mis-match between the reading device and
the printed symbol, or to a defective reader or decoder. A mis-read may
occur as as substitution error (the reader substitutes an incorrect
character) or as a transposition error, or as a missing character in a
The narrowest of bars, sometimes referred to as the X dimension. Wider
bars and spaces are stated as multiples of this narrow bar.
Modulo Check Character(s) -
The modulo check character is based on the remainder in a mathematical
formula where characters within the data string are assigned weighted
values, summed and then divided by the modulus. This value is then
appended to the data string. Modulo check characters are used to ensure
the accuracy of a data scan.
Number System Character -
The first digit or left hand digit in a U.P.C., number. This digit
identifies the type of manufacturer or how the bar code will be used.
For example "0, 6 and 7" are generally used in the retail industry,
while "3" is assigned to the health and drug manufacturing industries.
OCR - Optical Character Recognition.
OCR-A; OCR - Abbreviations commonly applied to the character set contained in ANSI Std. X3.17-1974 (A) and ANSI Std. X3.49-1975 (B).
for Data Exchange by Tele-Transmission in Europe) - a group that
represents the interests of the automotive industry in Europe;
equivalent of AIAG in America.
The property of a substrate material that minimizes show-through from
the back side or the next sheet. The ratio of the reflectance with a
black backing to the reflectance with a white backing. Ink opacity is
the property of an ink that prevents the substrate from showing through.
Picket Fence Code - A bar code printed in a horizontal position such that the individual bars appear like the slats in a picket fence.
Print Contrast Signal (PCS)
- Compares the amount of light reflected by the bars, in contrast to
the amount of light reflected by the spaces in a bar code symbol. The
Print Contrast Signal value is the bar reflectance expressed as a
percentage of the space reflectance.
Print Quality -
The measure of compliance of a bar code symbol to the requirements of
dimensional tolerance, edge roughness, spots, voids, reflectance, PCS,
quiet zone, and correct encoding.
A measure of the smallest "X dimension" printable by a particular
device or method. Also the measure of ability of a scanner to
distinguish a bar code symbol.
Shipping Container Code) - with a secure bar code symbology,
UCC/EAN-128. This combination allows all participants in the supply
chain to use a common, standard solution for their individual tracking
and tracing needs.
A bar code or symbol using a checking algorithm which can be
independently applied to each character to guard against undetected
Any of the light elements between the dark bars of a bar code, which
may or may not carry encoded information. The space may be formed by the
substrate, or by a colored ink which is lighter in color than the bars.
Slot Reader -
A bar code reading device requiring the substrate be drawn through a
narrow slot to fix the position of the bar code symbol relative to the
face of the bar code scanner. Typically used for scanning badges or
- A specific range of wavelengths or light, from a minimum to a
maximum, often named after a central value. The value of 633 nanometers
is visible light, while 900 nanometers represents infrared light.
Spectral band B633 includes those wavelengths (plus or minus 5 percent)
of the 633 nanometer peak. Spectral band B900 includes those wavelengths
(plus or minus 10 percent) of the 900 nanometer peak. The spectral band
or scanning device is generally listed in bar code specifications.
STAC (Symbol Technical Advisory Committee) to the Uniform Code Council Inc.,
Stacked Codes -
16K, Code 49 and PDF417 are examples where a bar code symbol is broken
into sections and "stacked" one upon another in order to increase the
information density in the bar code symbol.
Start/Stop Characters -
A distinct character or pattern of bars used at the beginning and end
of each bar code symbol, which provides initial timing references and
direction of read information to the decoding logic.
An executable program which is loaded into computer memory, is
initialized and remains in memory awaiting a specific instruction in
order to accomplish its execution. TSR stands for "Terminate and Stay
Resident". The TSR is normally a device driver intended to perform
specialized functions such as driving a serial port or directing data
from the serial port to the keyboard buffer.
Code Council, Inc.) - is the central management and information center
for manufacturers, distributors and retailers participating in the
U.P.C. system. This organization is not a government agency and is an
administrative council which exists specifically to develop standard
product and shipping container codes, control the issuing of company
identification codes, provide detailed information and to coordinate the
efforts of all participants. Although membership in the UCC is
voluntary it is required to obtain a U.P.C. identification number. For
more information access http://www.uc-council.org
UCC/EAN-128 is not intended to be used for data to be scanned at the
point of sales in retail outlets. UCC 128 facilitates the encoding of
the full 128 ASCII character set. The use of three different character
sets (A, B and C), one of the most compact linear bar code symbologies.
Character set C enables numeric data to be represented in a double
density mode. Here, two digits are represented by only one symbol
character saving valuable space. This symbology uses two independent
self-checking features which improves printing and scanning
Product Code) - is a 12-digit all-numeric code that identifies the
company/product combination. The code uses a six-digit number to
uniquely identify each company coupled with a five-digit number to
identify each of the company's products. The combination of these eleven
digits plus a check character form the 12-digit U.P.C. number which
uniquely identifies one and only one item.
According to a new independent capacity
study commissioned by the Uniform Code Council, Inc. (UCC), the
organization will deplete its supply of new company prefixes for the
12-digit Universal Product Code (U.P.C.) numbers by the year 2005. To
provide for continued expansion of the code system and the inclusion of
new companies in the future, the UCC has established a sunset date for
its membership to accept the 13-digit EAN-13 code as well as the U.P.C.
at the point of sale no later than January 1, 2005. EAN-13 is the global
counterpart of the U.P.C. For more information access
(Uniform Symbol Specification) - The current series of symbology
specifications published by AIM; currently includes USS-I 2/5, USS-39,
USS-93, USS-Codabar and USS-128.
The technical process by which a Bar Code symbol is evaluated to
determine whether it meets the specification for the specified symbol.
A device that measures a symbol's bars, spaces, quiet zones, and
optical characteristics to determine whether it meets the requirements
of a specific symbol. A verifier should not be confused with a bar code
An area within a bar (of a bar code symbol) which is of high
reflectance relative to the dark reflectance criteria, i.e. the bar or
character is poorly inked, or where the intended printed area is
missing. A void may cause a mis-read or cause the reader for fail to
read the symbol.
A handleld reading device in the form of a pen or wand, which requires
the user to make contact with the printed symbol and stroke the barcode
several times in a uniform and complete fashion. If the stroke is
non-uniform, or is too rapid, or too slow the wand reader will not read
the bar code symbol. Many wands are being replaced with more effective
and "user-friendly" reading device, such as CCD readers or Laser
Wide to Narrow Ratio -
The relationship of the wide to the narrow element widths, in a bar
code having two element widths. Generally between 2.0 to 1 through 3.2
X Dimension - The dimension of the narrowest element (bar or space) in a bar code symbol.
Zero Suppression - A technique used to shorten U.P.C. codes by removing zeros from the bar code in a predetermined manner.
2-Dimensional Symbology -
A machine readable symbol composed of rows of encrypted data arranged
in a rectangular or square pattern. The rows of data may be composed of
bar code strips, "stacked" to form the two-dimensional block pattern or
arranged as a checkerboard "matrix" of typically square elements.
Examples of 2-Dimensional Symbologies are: