Question

What is the Barcode - What is a barcode??

Accepted Answer

A representation of data that can be read by a machine  barcodes are either linear barcodes  one dimensional representations of data that are made up of a pattern of parallel lines and spaces  or matrix barcodes  two dimensional representations of data that are made up of a square or rectangular pattern  matrix  of black and white cells or modules     although other colours can be used       Matrix barcodes are a newer form of barcodes and are able to represent more data per unit area  they are commonly used on small items or on surfaces where there is only a small area available for adding a barcode  although larger versions can be created   They are commonly used on small electronic components  food packaging  and are often printed onto labels to allow a variety of objects to be tracked  Perhaps the most well-known type of matrix barcode is the QR code  which has become extremely popular for use in marketing and promotional campaigns      Linear barcodes are made up of a pattern of lines  known as bars and usually black in colour  and spaces  known as intercharacter gaps   they can be either    continuous codes     the intercharacter gaps are part of the code  or    discrete codes     the intercharacter gaps are not part of the code  and the bars can either run vertically  Picket Fence orientation  or horizontally  Step Ladder orientation   Data is represented by varying the width  and sometimes the height  and spacing between the bars  this data is most commonly a numerical code that will bring up a record or set of data information when the barcode is scanned  For example  barcodes are commonly used to scan products at POS  point of sale   where the barcode will be used to bring up the product  pricing  and inventory information for that particular item      Barcodes usually begin and end with a clear area or    quiet zone     which is a blank space used to clearly indicate where the barcode begins and ends  The first and last characters in a barcode are known as the start character and stop character respectively  these characters provide the barcode reader with start and stop reading instructions and also indicate the orientation of the barcode  Some barcodes can be read successfully independently of the orientation  i e  they can be scanned left to right or right to left      these are known as bi-directional barcodes  The rest of the barcode will be made up of characters that represent the data that has been encoded into the barcode along with a check character or check digit that is used to perform a mathematical check to confirm that the barcode has been read correctly  The symbol density of a barcode refers to the number of data characters that can fit on a specific unit length and is usually expressed as the CPI  characters per inch       While barcodes may represent a variable length code  the number of characters in the code can fit within a range   they are most commonly used to represent a fixed length code  such as a GTIN  GTIN stands for Global Trade Item Number and is a globally used standard for identifying trade items  products or services   The GTIN standard has incorporated a number of other standards  including International Standard Book Number  ISBN   International Standard Serial Number  ISSN   International Standard Music Number  ISMN   International Article Number  EAN   and some Universal Product Codes  UPC   and may be 8  12  13  or 14 digits long  Usually  these standards are made up of a 2-3 digit number representing the country of origin  or language   followed by a manufacturer or company number  followed by product or item number  and ending with a check digit      Barcodes are usually used to carry data that can be used to look up information about the item that the barcode is attached to  which makes them incredibly popular for use in the retail industry  where they can be used to look up product and pricing information at point of sale  to keep track of stock levels  to track and evaluate shopping habits  and to redeem coupons or vouchers  They can also be used in a variety of applications and environments to keep track of  and collate data about  people and items  for example  barcodes may be used on employee IDs to track work hours  are used on event tickets  for concerts  theatre performances  sporting events etc  to track admissions  can be used to track parcels and mail items  and are used to sort and direct airline luggage  They are commonly found in healthcare facilities and hospitals  where barcodes can be used on wristbands for patient identification  on surgical instrument kits to track equipment  and ensure sterilisation procedures are followed   to process medical samples for testing and track medical supplies  including blood infusions   and are used to improve the efficiency of medication management  including documenting the exact medications that are given to patients       Barcodes are usually read by optical scanners called barcode readers or barcode scanners  although they can also be read using smartphone apps   Most of these devices work in the same way  light is directed at the barcode and the intensity of the light that is reflected back into the reader is converted into an electrical signal  The dark bars and light intercharacter gaps cause the intensity of the reflected light to fluctuate  which makes the electrical signal oscillate and form a pattern that can be converted into digital information and correlated to the database of information stored in a computer or device      Barcode readers can be    Hand-Held     small pen-like devices that can be moved over the barcode  often used by carriers to scan parcels      Fixed-Beam     slightly larger devices where the barcode is placed under a non-moving beam of light to be scanned      Moving-Beam     the devices move a beam of light back and forth in a straight line or X-shaped or star-shaped pattern  most commonly found in supermarkets and large retail POS   or    Video-Image     a video signal of the barcode is taken and then decoded

QR Code - What is a QR code?

Definition of QR CODE: