A bar code (often seen as a single word, barcode) is the small image of lines (bars) and spaces that is affixed to retail store items, identification cards, and postal mail to identify a particular product number, person, or location. Barcode contains information about a product like; price & weight of the product, date of manufacturing and expiry, name of the manufacturer etc. Barcode is allocated by an international institution set up for this purpose. Every product has a unique barcode all over the world.