Over view:
A barcode is an optical machine-readable representation of data,
which shows data about the object to which it attaches. Originally,
barcodes represented data by varying the widths and spacing of parallel
lines and may be referred to as linear or one dimensional (1D).
Later they evolved into rectangles, dots, hexagons and other geometric
patterns in two dimensions (2D).
Although 2D systems use a variety of symbols, they are
generally referred to as barcodes as well.
Barcodes originally were scanned by special optical scanners called barcode readers. Later, scanners and interpretive software became available on devices including desktop printers and smart phones. 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 for which they have become almost universal. Their use has spread to many other tasks that are generically referred to as automatic identification and data capture (AIDC).
Other systems have made inroads in the AIDC market, but the simplicity, universality and low cost of barcodes has limited the role of these other systems until the first decade of the 21st century, over 40 years after the introduction of the commercial barcode, with the introduction of technologies such as radio frequency identification, or RFID.
How it works:
Due to advances in technology, barcode labeling has now replaced the usual method of pricing goods for sale. Barcode labels are a series of continuous white spaces and black stripes of different widths which can be scanned and interpreted by a barcode scanner.
The coding of barcode labels is done using different symbols that can be read and interpreted by designated software or a barcode scanner. This type of system is used in a variety of applications for quick billing, precise calculations and maintaining inventory records.