What is bar code? It is method of automatic identification and data collection. The first patent for a bar code type product (US Patent #2,612,994) was issued to inventors Joseph Woodland and Bernard Silver on October 7, 1952. The Woodland and Silver bar code can be described as a “bull’s eye” symbol, made up of a series of concentric circles.
Examine the 1958 patent drawing to the left that depicts the Woodland’s and Silver’s bar code label and the 1958 patent drawing below right of the inventors’ bar code scanner technology. The photo below left is an example of today’s U.P.C. bar code on a product package.
In 1948, Bernard Silver was a graduate student at Drexel Institute of Technology in Philadelphia. A local food chain store owner had made an inquiry to the Drexel Institute asking about research into a method of automatically reading product information during checkout. Bernard Silver joined together with fellow graduate student Norman Joseph Woodland to work on a solution.
A barcode is an optical machine-readable representation of data. Originally, bar codes represented data in the widths (lines) and the spacings of parallel lines, and may be referred to as linear or 1D (1 dimensional) barcodes or symbologies. They also come in patterns of squares, dots, hexagons and other geometric patterns within images termed 2D (2 dimensional) matrix codes or symbologies. Although 2D systems use symbols other than bars, they are generally referred to as barcodes as well.
The first use of barcodes was to label railroad cars, but they were not commercially successful until they were used to automate supermarket checkout systems, a task in which they have become almost universal. Their use has spread to many other roles as well, tasks that are generically referred to as Auto ID Data Capture (AIDC). Other systems are attempting to make inroads in the AIDC market, but the simplicity, universality and low cost of barcodes has limited the role of these other systems. It costs about US0.5¢ to implement a barcode compared to passive RFID which still costs about US$0.70 to US$1.30 per tag.
Barcodes can be read by optical scanners called barcode readers, or scanned from an image by special software. Scanning software for 2D codes is built-in to or available for many mobile phones, and is especially popular in Japan, India & Europe.