In this post, we aim to teach you how to read the numbers in the various types of barcodes that we see every day in every product that we find inside the grocery.
A barcode or universal product code is simply a very rapid way of entering numeric data into a computer which can be the electronic teller in the supermarket or the computerized inventory of a warehouse. While this subject is something that teachers do not teach inside the classroom, we thought that this post will provide some insight to students and teachers alike on the purpose of the barcode and how to read it.
Computers are absolutely better than humans when it comes to processing numbers at speed. Computers are however ultimately robots because they work on what they are programmed or designed for. The barcodes depend on the lasers or beam of pure light. The black lines do not reflect the laser very well at all and therefore they are recorded as a one. The white lines reflect the laser very well and are recorded as zeroes.
How do barcodes work?
The barcode looks like a series of white and black lines and represents a 12-digit number. It also comes printed with numbers beneath the series of lines in case the barcodes are too distorted to be read or scanned at all.
What do the numbers in the barcode represent?
- The first number is the product type. So it can be potatoes by weight, birthday cards, magazines, or whatever the number represents.
- The next five numbers are the manufacturer code.
- The next five numbers on the right-hand side are the product code.
- The final and last number is the check digit.
Here is what can’t be seen by the naked eye. Each element of the barcode is divided into 7 non-visible modules that consist of bars and spaces. Each unique group of 7 bars and spaces is interpreted by the computer as 1 digit only.
The numbers on the right side of the barcode are the optical opposites of the numbers on the left side of the barcode. This is so the computer knows which way up the barcode is being scanned to avoid interchanging of items or products.
What is the check digit?
This is the computer’s way of policing the system to make sure that the first digits of the barcode are read correctly. This involves a bit of computation which will not be discussed in this post but featured in the video below.