When questioned, most people would probably tell you they are not familiar with a UPC reader. However, this technology has been in existence for quite some time. Chances are whenever you make a purchase at your local grocer or department store chain; the products you buy are scanned using this type of tool. Each specific item for sale contains a UPC or Universal Product Code. In the past, the most widely used code of this type was referred to as the version A code. Recent updates are requiring all users in the U.S. to transfer to what is known as an EAN/UCC 13 code. This code type has already been in use throughout most of the world and contains an extra digit in the barcode.
The more familiar version A code contains a series of twelve digits that are scanned by the UPC reader. The digits in a version A code are arranged according to their use. The first number in each code is used to identify the product, For example, “0” is used to represent groceries or food products. The next ten digits are used to identify both the manufacturer’s code and the product code. The five digits for the manufacturer’s code are located on the left side of the barcode and the five digits for the product code on the right. Although a UPC reader checks all digits in the barcode, it can read the digits on the right side of the barcode separately from those on the left. The last digit in the barcode is known as the modulo check number. It can determine if all of the other digits in the code were read properly. If an error it detected, the item needs to be scanned again by the UPC reader.
UPC barcodes were originally only used by grocery stores in an effort to both keep track of their inventory and enable cashiers to process items more quickly. Their efficiency and reliability soon caused other retailers to implement the use of UPC readers. Today nearly all of the items we purchase contain some type of UPC barcode.