GLOSSARY
ANSI
The American National Standards Institute is a non-governmental organization responsible for the development of voluntary manufacturing standards.
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.
Bar Code Character
A single group of bars and spaces, which represent an individual number, letter, punctuation mark or other symbol.
Bar Code Density
This value represents the number of possible characters contained in a lineal inch.
Bar Code Label
A suitable label, which carries a bar code and is affixed to an article.
Bar Code Symbol
A sequence of rectangular shapes and intervening spaces used to encode a string of data. A bar code symbol typically consists of five parts: 1-a leading quiet zone, 2-a start character, 3-data character(s) including an optional check character, 4-a stop character and 5-a trailing quiet zone.
Bar Length
The bar dimension perpendicular to the bar width. Also called height.
Bar Width
The thickness of a bar measured from the edge closest to the symbol start character to the trailing edge of the same bar.
Bar Width Reduction
Reduction of the nominal bar width dimension on film masters or printing plates to compensate for printing gain.
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 some bar codes that allow decoding of the symbol regardless of whether scanned in a forward or backward direction.
Character
1. A single group of bars and spaces which represent an individual number, letter, punctuation mark or other symbol.
2. A graphic shape representing a letter, numeral or symbol.
3. A letter, digit, or other symbol that is used as part of the organization, control or representation of data.
Character Alignment
The vertical or horizontal position of characters with respect to a given reference line.
Character Set
Those characters available for encodation in a particular bar code symbology.
Character Density
Generally given as the number of characters per inch (cpi), This dimension is the length, in linear inches, required to encode one character.
Code
A set of unambiguous rules specifying the way in which data may be represented. Numbers and letters used to represent information.
Codabar
A bar code format in which four bars and three spaces represent the digits 0 through 9 and certain special characters. The code is characterized by four unique start/stop codes, variable intercharacter spacing, and code densityof up to 10 character per inch.
Code 39
A variable length, bi-directional, discrete, self-checking, alpha-numeric bar code. Code 39 encodes 43 characters; zero through nine, capital A through capital Z, minus symbol, plus symbol, forward slash, space, decimal point, dollar sign and percent symbol. Each character is encoded by 9 bars, 3 of which are always wide.
Code 93
A variable length, continuous, alpha-numeric bar code. Code 93 encodes all 128 ASCII characters. Forty-three of code 93\'s character set correspond to code 39\'s character set, and 4 additional characters are used as control characters when encoding the full ASCII character set in code 93\'s expanded mode. Each character is encoded with 9 modules composed in a pattern of 3 bars and 3 spaces. Each bar and space width may be one, two, three or four modules wide.
Code 128
A variable length, bi-directional, continuous, self-checking, alphanumeric bar code. Characters in Code 128 consist of three bars and three spaces. Bars and spaces may be one, two, three, or four modules wide. The total character width is 11 modules. Code 128 obtains its name from its capacity to encode the full ASCII 128 character set.
Contact Scanner
A bar code scanner that requires physical contact between the encoded medium and the scanner.
Continuous Code
A bar code symbol where all spaces within the symbol are parts of characters, e.g., USS-I 2/5. There is no intercharacter gap in a continuous code.
Continuous Bar Code Symbol
Bar codes, where the spaces serve as part of the character\'s definition of bars and spaces. There is no intercharacter space in continuous codes. See Discrete bar code symbol. An example of a continuous bar code symbol is Interleaved 2 of 5 as opposed to code 39, which makes use of intercharacter spaces.
Data Identifier (flag character)
A character (or set of characters) that uniquely defines the specific use of the data or the general category of the data field encoded in the bar code symbol following it.
Decodability
Measure of a printed bar codes\' ability to be deciphered accurately by a bar code reader.
Decode
Decipher the information represented within a bar code symbol.
Decoder
1) The internal electronics of a bar code reading device that translates the received input signals into meaningful data.
2) The portion of a bar code reader that performs the decoding function.
Demand Printer
A printer capable of creating individual documents one at a time, as directed.
Discrete Bar Code Symbol
Refers to a type of bar code symbol, in which no information is contained in the width of the spaces between characters. Due to this difference the intercharacter space is allowed to vary dimensionally within wider tolerances than those specified for the bars and spaces of the continuous symbol. An example of a discrete bar code is Code 39.
EAN
International Article Numbering (European Article Numbering), a superset of U.P.C., used primarily in retail food or merchandise sales.
Element
A single bar or space.
FACT
Federation of Automated Coding Technology -- A bureau of AIM consisting of organizations that use and promote automatic identification among their members.
Field
Any group of characters defined as a unit of information. This differs from a line because one line may contain several fields.
Fixed-Length (code and field)
Refers to a symbol or code in which the data elements must be of a specific length.
Font
A specific size and style of printer\'s type.
Guard Bars
Bars, which furnish reference points for scanning devices, found at the beginning, middle and end of U.P.C., and EAN symbologies.
HIBC Symbol and Code
Health Industry Bar Code, format and symbology for automated data entry.
Human Readable
Refers to the portion of a bar code that can be read and understood by humans. This readable part of the symbology represents the bar code contents.
Intercharacter Space
The space between two adjacent bar code characters in a discrete code. Also called the intercharacter gap.
Interleaved Bar Code
A continuous type bar code in which the characters are paired together with the bars representing the first character and the spaces representing the second character.
Interleaved 2 of 5
Interleaved 2 of 5 is a continuous, self-checking, numeric symbology employing two element size widths. Characters are paired together with each character composed of five elements, two wide and three narrow, representing numbers 0 through 9; with the bars representing the first character and the interleaved spaces representing the second character.
Ladder Code
A bar code printed in a vertical position such that the bars can be thought of as rungs on a ladder. See Picket fence.
LOGMARS
(LOGistic applications for Marking And Reading Symbols) A Department of Defense program to place Code 39 symbols encoding specific data on all items sold to the Federal Government.
Matrix Symbols
A symbol that 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 scanners.
Mil
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
With an understanding that 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. The minimum reflectivity difference is generally used as part of a bar code\'s specification.
OCR
Optical Character Recognition.
OCR-A; OCR-B
Abbreviations commonly applied to the character set contained in ANSI Std. X3.17-1974 (A) and ANSI Std. X3.49-1975 (B).
Opacity
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.
Orientation
The alignment of the symbol\'s scan path. Two possible orientations are horizontal with vertical bars and spaces (picket fence) and vertical with horizontal bars and spaces (ladder).
Overhead
The fixed number of characters required for start, stop and checking in a given symbol. For example a symbol requiring a start/stop and two check characters contains four characters of overhead. Thus, to encode three characters, seven characters are required.
Pitch
Rotation of a barcode symbol about an axis parallel to the direction of the bars.
Print Contrast Signal (PCS)
Found as a part of a bar code specification the Print Contrast Signal 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 encodation.
Quiet Zone
The Quiet zone is the area preceding the beginning of a bar code and following the end of the bar code, sometimes call the clear area. The quiet zone should contain no dark markings that could confuse or be misinterpreted by a scanning device. A minimum of 10 times the narrowest bar element or a quarter of an inch, whichever is greater, should be maintained for the quiet zone area.
Self-Checking
A bar code or symbol using a checking algorithm which can be independently applied to each character to guard against undetected errors.
Skew
Rotation of a bar code symbol about an axis parallel to the symbol\'s length.
Space
The lighter element of a bar code usually formed by the background between bars.
Space Width
The thickness of a space measured from--the edge closest to the symbol\'s start character, to--the trailing edge of the same space.
Spectral Band
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., (see UCC).
Stacked Codes
16K and Code 49 are examples where a long symbol is broken into sections and stacked one upon another similar to sentences in a paragraph. Extremely compact codes.
Standard
A set of rules, specifications, instructions and directions to use a bar code or other automatic identification system to your profit Usually issued by an organization, e.g., Logmars, HIBCC, U.P.C., etc.
Start/Stop Characters or Patterns
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.
Symbol
A combination of characters including start/stop characters, quiet zones, data characters and check characters required by a particular symbology, which form a complete, scannable entity.
Symbol Density
Generally given as the number of characters per inch (cpi), Limited by the width of the narrowest bar or space.
Symbol Length
The measured length of the bar code from beginning to end including quiet zones.
Tilt
Rotation of a bar code symbol about an axis perpendicular to the substrate.
UCC
Uniform Code Council, formerly Uniform Product Code Council; the organization which administers the UPC and other retail standards.
UCC Company Prefix
Part of the UDCC-12 Data Structure consisting of a UCC prefix and a company number allocated by the UCC.
UCC Prefix
A one-digit index number administered by the UCC, denoting the format and meaning of a particular Element String contained within the UCC-12 numbering structure.
UCS
Uniform Container Symbol.
UPC (Universal Product Code)
Most commonly recognized as the 12 digit code found on grocery shelf items. Adopted by the U.S. grocery industry and later by other retail industries. The U.P.C. is composed of a number system character, a five digit manufacturer number assigned by the UCC, a five digit product code assigned by the manufacturer, and a modulo 10 check digit as the 12th digit.
USS
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.
Variable Length Symbology
A symbology whose length is not predetermined beyond the basic necessity for characters, such as start/stop codes. Examples of fixed length symbologies are: U.P.C.-A, EAN-13, etc., while Code 39 is an example of a variable length alphanumeric code. Code 39 can support any data length from one character up to a maximum determined by the reading decoding device, generally 32 or more characters.
Verification
The technical process by which a Bar Code symbol is evaluated to determine whether it meets the specification for the specified symbol.
Verifier
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.
Vertical Bar Code
A bar code pattern presented in such orientation that the symbol from start to stop is perpendicular to the horizon. The individual bars are in an array appearing as rungs of a ladder.
Vertical Redundancy
The availability of multiple scan paths through a symbol to minimize the effects of localized printing defects. This increases the ability to scan a symbol.
Void
The undesirable absence of ink in a bar.
Wide to Narrow Ratio (N)
The relationship of the wide to the narrow element widths, in a bar code having two element widths. Generally some where between 2.0 to 1 through 3.2 to 1.
X Dimension
The average specified width of the narrow element in a bar code determined by the application and/or symbology specification.
