In the UPC-A barcode, each digit is represented by a seven-bit sequence, encoded by a series of alternating bars and spaces.
"UPC" stands for Universal Product Code. UPC bar codes were originally created to help grocery stores speed up the checkout process and keep better track of inventory, but the system quickly spread to all other retail products because it was so successful.
UPCs originate with a company called the Uniform Code Council (UCC). A manufacturer applies to the UCC for permission to enter the UPC system. The manufacturer pays an annual fee for the privilege. In return, the UCC issues the manufacturer a six-digit manufacturer identification number and provides guidelines on how to use it. You can see the manufacturer identification number in any standard 12-digit UPC code.
