Universal Product Code
The Universal Product Code (UPC) is a barcode symbology (i.e., a specific type of barcode) that is widely used in the United States, Canada, the United Kingdom, Australia, New Zealand, and in other countries for tracking trade items in stores.
The most common form, UPC-A, consists of 12 numerical digits, which are uniquely assigned to each trade item. Along with the related EAN barcode, the UPC is the barcode mainly used for scanning of trade items at the point of sale, per GS1 specifications. UPC data structures are a component of GTINs (Global Trade Item Numbers). All of these data structures follow the global GS1 specification which is based on international standards. Some retailers (clothing, furniture) do not use the GS1 System (other bar code symbologies, other article number systems). Other retailers use the EAN/UPC bar code symbology but without using a GTIN (for products brands sold at such retailers only).
History
Wallace Flint proposed an automated checkout system in 1932 using punched cards. Bernard Silver and Norman Joseph Woodland, a graduate student from Drexel Institute of Technology (now Drexel University), developed a bull's-eye style code and applied for the patent in 1949 (US patent 2612994, Norman J. Woodland and Bernard Silver, "Classifying Apparatus and Method", issued October 7, 1952 ).