Barcodes are symbols used to store bits of data. They are read by either scanning a point of light across the symbol or capturing a video image of the symbol and measuring the lengths of white spaces and black bars. Barcodes are used for identification, tracking, inventory, and as part of retail point of sale (POS) systems.
Barcodes are integral to machine-to-machine communication, transmitting bits of data often without human intervention. The lengths and positions of the spaces and bars are analyzed by a computer program and the data is extracted. The relative widths of both the bars and spaces code the data stored in the bar code. The bar code reader detects these relative widths and decodes the data from the bar code.