The barcode it is a technology that has revolutionized the way we manage and identify products of all kinds. It is a unique identification code made up of black and white bands of different thicknesses which is scanned and “read” using special sensors which often use laser technology. Its origins date back to the 1940s, when two engineering students, Bernard Silver And Norman Joseph Woodlandwere inspired to create a system that could simplify and speed up payment transactions in supermarkets. Over time, the barcode has become not only a symbol of efficiency in the sales process, but also an important innovation that has transformed our way of interacting with the products we use every day. Let’s briefly review the barcode history and let’s find out in more detail how it works.
How the barcode was born
In the 1948 a student at Drexel Institute of Technology, Bernard Silverheard the president of a local grocery chain request a method to automatically read product information. This prompt led Silver to contact his fellow student Norman Woodland. The two thus began working on different systems, but it was a seemingly ordinary day, on a beach in Miami Beach, that a brilliant intuition was born. Inspired by Morse code, Woodland used the fingers of his hand to draw the first vertical dots and lines on the sand, which would soon give life to what we all know today as barcode. In describing that moment, Woodland stated:
I remember I was thinking about dots and lines when I stuck my four fingers in the sand and, for some reason (I didn’t know), I pulled my hand towards me and I had four lines. I said «Damn! Now I have four lines and they could be wide lines and narrow lines, instead of dots and dashes. Now I have a better chance of finding the damn thing.” Then, just a few seconds later, I took my four fingers (they were still in the sand) and swirled them in a circle.
Their invention was patented in 1949 and officially recognized in 1952.
Despite the patent, the barcode took years to find a practical application in commerce. In fact, the first real experimentation with this technology only took place in 1972 in a Cincinnati department store, but was unsuccessful. In the 1974thanks to Woodland, who had sold the patent to IBMthe code UPC (Universal Product Code) was first used in a Troy’s Marsh Supermarketin Ohio. It was shortly after 08:00 in the morning Wednesday 26 June 1974 that the first item marked with the UPC (a pack of chewing gum) was scanned at the checkout of that supermarket. A simple gesture that has undoubtedly contributed to changing the way we shop.
In fact, during the 70s and 80s, the barcode rapidly spread Europeincluding theItaly. More precisely, in 1977twelve European countries began using barcodes, leading to the creation of the EANa non-profit identification standards organization, known today as GS1. In ItalyIn the 1978was born Indicator codetoday it is known as GS1 Italywhich is currently the only body authorized in the “Bel Paese” to issue company prefixes and GS1 barcodes.
How the barcode works and how it is read
Before understanding in broad terms how the barcode worksit is worth specifying that there are countless types, each of which has very specific characteristics. One of the most widespread typologies is that represented by GS1 EAN-13 and for this very reason it will be what we will “zoom in” on now to understand how this technology works.
The GS1 EAN-13 barcode consists of moduleseach of which is occupied by a dark bar or white space. This alternation of black columns and white spaces is linked to the reflection of light and serves to allow the code to be decoded using a barcode reader. When the scanner’s laser passes over such a code, it reads 95 identical columnscalled “modules”, evaluating the amount of reflected light. Computers interpret dark bars, which do not reflect light, as “1” and white spaces, which reflect a lot of light, like “0”.
The laser reader then begins the scan of the 95 modules: the first does not reflect light, so it is a “1”, the second reflects light and is a “0”, the third is similar to the first and is read as “1”, and so on, until the computer obtains the complete sequence of 95 digits made up of many “0” and “1”. Subsequently, this very long number is divided into 15 sections. The first 12, each made up of 7 modules, symbolically represent 12 of the digits displayed below the bars. The remaining 3 sections, which include 3 modules at the ends and 5 central modules, act as reference points for the computerwhich can thus be able to determine the beginning and end of the code, as well as the position of the digits in the first and second halves.
Speaking of the digits placed at the bottom of the barcode, these represent the manufacturer, whose prefix is assigned by the GS1 body (which we mentioned in the previous chapter), while the first two digits identify the origin of the product. The next five refer to the code of the same and, finally, the last digit on the right is a “check digit”, which guarantees that the code has been read correctly. The computer’s interpretation of all this data read with the laser scanner obviously occurs in fractions of a second!
In recent years, with the advent of new technologies, barcodes have evolved their shape, giving space to two-dimensional codeslike i QR codewhich can store a greater amount of information and are easily readable even via smartphone. Despite this, the one-dimensional barcode continues to be used widely, demonstrating its resilience and ability to adapt to the needs of modern commerce. The next time you are queuing in front of a supermarket checkout and observing the products passing under the scanner, perhaps you will remember the history that led to the birth of this widely used technology and how it works!
