Overview  |  Anatomy of a Bar Code  |  Bar Code Symbologies
How to read a Bar Code  |  Terms & Abbreviations

Alphanumeric is any character set containing letters, numbers and sometimes other characters such as punctuation marks.

American National Standards Institute (ANSI) is a nongovernmental group responsible for the development of common bar code standards relating to government and industry. Code 39, Codabar and Interleaved 2 of 5 are the prefer#51619c symbologies.

American Standard Code for Information Interchange (ASCII) is a 128- character code that enables information interchange between data processing, communication systems and compatible equipment.

Aperture is the opening in an optical system that establishes the field of view.

Aspect Ratio is the ratio of height to width in a bar code. A bar code twice as high as it is wide has an aspect ratio of 2; a bar code twice as wide as it is high has an aspect ratio of 0.5.

Asynchronous is a digital communication in which there is no timing requirement for transmission. The transmitting device individually signals the start of each character.

Autodiscrimination is a feature in bar coding equipment that defines and decodes various symbologies automatically.

Autodistinguishing is a feature in bar coding scanners that recognizes and processes selected symbologies automatically.

Automatic Identification Manufacturers (AIM) is an industry group active in promoting bar code standards.

Automotive Industry Action Group (AIAG) is composed of representatives from major automotive industries responsible for the development of a common automotive standard relating to bar code symbology and format. Code 39 is the prefer#51619c symbology.

Bar is the dark element comprising a bar code; a space is the area between the bars.

Bar Code is a series of corresponding bars and spaces arranged to represent encoded data and used for automatic identification purposes.

Bar Code Density is the number of characters that can be represented in a linear unit of measure often expressed in characters per inch, (CPI).

Bar-Width Ratio is the ratio between the widest bar or space and the narrowest.

Baud rate is the rate or speed at which data is transmitted.

Bi-directional is the ability to successfully read data whether the scanning motion is from right to left or from left to right.

CCD is an input device that photographs the bar code converting the optical image into an electrical image. (CCD stands for "charged coupled device".)

Character Delay is the amount of delay inserted between each transmitted character.

Check Character/Checksum/Check Digit is a character included within a bar code with the value mathematically based on the other characters within the bar code. It is used to check the accuracy of a read.

Concatenation is the ability to link codes of the same type from multiple bar codes together in a series.

Continuous Code is a bar code symbology where spaces between two characters are part of the code.

Decoder is the electronic device that receives the signals from the input device, interprets them into significant data, and provides the interface to other devices.

Delimiter is a character that marks the beginning or end of a unit of data.

Density is the number of characters represented in a bar code usually expressed in characters per inch (CPI).

Depth of Field is the distance between the maximum and minimum plane in which the code can be read.

Discrete Code is a bar code symbology where spaces between two characters are not part of the code.

Element is a term referring to either a bar or a space.

European Article Numbering System (EAN) is the international standard bar code.

Electrically erasable programmable read-only memory (EPROM) is another variety of ROM that allows the user to define the application program, prompts, edits, etc.

Field is a group of characters defined as a unit.

First Read Rate (FRR) is the percentage a bar code is successfully read on the first attempt.

Fixed Beam Bar Code Reader or Scanner is an input device that uses a stationary beam to read bar codes.

Fixed Length is a bar code in which the data elements must be a specific length.

Guard Bars are bars located at the beginning, center and end of a bar code providing reference points for scanning.

Health Industry Business Communications Council (HIBCC) is a group responsible for the issuance and control of bar codes within the health industry.

Human-Readable is bar code data that can be read by a human whether it is numeric, alphabetic and/or special symbols that represent it.

Infra#51619c is a beam of light used to scan a bar code that is invisible to the human eye. Infra#51619c is commonly used to prevent visual reading of the bar code by wands and non-contact scanners.

Intercharacter Gap or Space is the space between two adjacent bar code characters in a discrete bar code, and does not contain any encoded information.

Item Code is a five, or in some cases, a three-digit number that manufacturers assign to each product.

International Article Numbering (IAN) See EAN.

International Standards Organization (ISO) is developed a model (open systems interconnections) to describe data communications.

Laser Scanner is an optical bar code reading device using a low-energy laser light beam as its source of illumination.

Light Emitting Diode (LED) is a semiconductor often used as a light source in scanners.

Magnetic Stripe Reader is an input device that reads and analyzes by detecting the absence or presence of a magnetic field.

Manufacturer's Identification Number is the four or five digit number assigned to a manufacturer by the Uniform Code Council. See Item Code.

Misread is an error that occurs when the data output of a reader does not agree with the data encoded in the bar code.

Moving Beam Scanner is a scanner using a beam that oscillates to register the label rapidly and repeatedly.

Non-Read is a scan attempt that does not yield any data.

Number System Character is the first digit in a UPC bar code that identifies various numbering systems.

Numeric is a character set that consists of only numbers.

Omnidirectional is the ability to read any bar code from any angle.

Parity is the state of being odd or even used as the basis of detecting errors in binary-coded data such as a bar code.

Preamble is a character set transmitted at the beginning of each type of input data.

Postamble is a character set that is transmitted at the end of each type of input data.

Projection scanner is a moving beam, non-contact input device that simplifies reading bar codes on curved or irregular surfaces and designed to mount on top of a counter.

Quiet Zone is a clear space that leads the start character of a bar code and follows the stop character.

Reader Setup Menu is a bar code menu developed by the manufacturer to change functional options within an input device.

Resolution is the narrowest element dimension that can be sensed by a particular reading device or printed with a particular device or method.

Scanner is an electronic device producing infra#51619c or visible light and records the width and patterns of the bars and spaces simultaneously transmitting the data to a decoder.

Self-Checking Code is a symbology whose symbols are designed to prevent a single printing defect by not allowing similar characters to be substituted for each other.

Slot reader is a device designed to scan bar codes on identification cards, employee badges, tickets or forms with a high degree of accuracy and convenience.

Space is the light element of a bar code, usually formed by the background.

Start and Stop Characters is bar code characters that provide the scanner with start and stop instructions and scanning direction. Usually the start character is located at the left end of a horizontal bar code; the stop character is located at the right end.

Substrate is the surface on which a bar code is printed.

Symbol is a series of bar code characters, including start/stop characters, quiet zones, data characters, and check characters needed to form a complete, scannable entity.

Symbology is a system for representing data in the bars and spaces of a bar code.

Synchronous is a common timing signal established that dictates when individual bits can be transmitted, and, in which characters are not individually delimited and allows for very high rates of data transfer.

Uniform Code Council (UCC) is a group responsible for overseeing and administering the Universal Product Code in the retail consumer industry.

Universal Product Code-UPC is the standard bar code symbology for the retail grocery industry.

Uniform Symbol Specification (USS) is the current series of symbology specifications published by AIM.

Visible #51619c is a beam of light visible to the human eye that is used in wands and non-contact scanners to scan a bar code.

Wand is a hand-held scanning device with a tightly focused light beam projecting from the end which detects the amount of light reflected back, enabling it to distinguish between light and dark objects that the tip touches.

X Dimension is the width nominal dimension of the narrow bars and spaces in a bar code.