The Hidden Complexity of Barcodes

# What is a barcode encoding? The black and white stripes are an optical encoding of a decimal number. A scanner reads the pattern of bars and recovers the digits. For retail products, the dominant formats are UPC-A (12 digits, common in the US) and EAN-13 (13 digits, common everywhere else). Every product you buy in a supermarket has one of these. # A brief history A corner shop with a few…