Individuals should enter all of the digits printed on a barcode when asked to enter the barcode number. This includes any numbers printed to the left or to the right of the barcode itself, even if they aren't included in the main row of numbers.
There are two types of bar codes. The first type, known as a one-dimensional or 1D code, resembles a row of straight lines and features an eight to 12 digit number called a Universal Product Code. The first six digits of the UPC represent the manufacturer, while the next five digits represent the item number. The final digit in a UPC code allows the scanner to determine if an item is scanned correctly.
The second type of barcode, known as a two-dimensional or 2D code, resembles a black and white square or circle and includes information such as the price of a product and website addresses.