Google is celebrating the barcode and the humble strip of black and white is marking its 30th birthday in the UK.
Barcodes have a quiet ubiquity. They have proliferated to the point where few of us even notice them.
A US invention, they finally made their way to the UK in the late 1970s and in October 1979 a momentous event happened at a branch of Key Markets in Spalding, Lincolnshire. The barcode arrived at the till.
So came the beginning of the end for supermarket checkout staff mashing their fingers by spending a lifetime typing in price tags.
According to GS1 UK, the British branch of the global barcode regulator, there were 100 stores scanning at the till by 1984. It was 5,000 by 1991 and 10,000 two years later. By 1995, the figure was 20,000 and GS1 ceased bothering to count. The barcode had won.
But there was a degree of initial scepticism in the UK, says Andrew Osborne, chief technical officer of GS1 UK.
"There was a lot of suspicion in the 1970s. We had to have quite a campaign going around various consumer groups to say that the removal of individual price stickers was not going to lead to people being overcharged."
And the red lasers of the scanners also prompted concern among unfamiliar shoppers.
"People associated them with Star Wars and were concerned that they were going to be burned or blinded."
The credit for inventing the barcode is often given to Bernard Silver and Norman Woodland of Philadelphia's Drexel Institute of Technology. As well as the barcodes familiar today, a circular or bull's-eye model was also considered. Further work was done on a system for train carriages in the 1960s before the barcode finally made its debut in a US shop in 1974.
An obstacle in the UK, as elsewhere, was the slowness of manufacturers to put barcodes on their products.
"In those early days there were very few products that carried the barcode marked by the manufacturer," says Mr Osbourne. "What the retailers had to do was to put on sticky labels with barcodes on and that was quite difficult. They would have these Heath Robinson contraptions in the back of the store where they were taking goods, unpacking them and applying labels.
"Over the next few years they persuaded the suppliers to put the barcodes on at source. Then it could take off in a big way."
By 1982, 70% of UK grocery goods had barcodes.
The key aspect of the barcode boom, and the one that not all shoppers might appreciate, is that the mere obtaining of the price at the till is only a small part of the benefits.
A fundamental purpose of the barcode is to generate information for a database. In pre-barcode shops, of medium or large size, if you ran out of tomato sauce, it took an alert checkout person or stock manager to notice this had happened. In the gap between running out and restocking, customers could go elsewhere.
Under a barcode system it is easy to record every transaction and link it into the supply chain, so you never run out of anything. Shops adopting it in the early years soon found they could increase sales.
The next big thing in barcodes is people using their mobile phone cameras as readers.
And the barcode has a life in many logistics systems. It was adopted early by the US Department of Defence. And parcels are now a common home for a black and white strip for tracking purposes.
Shop barcodes usually represent numbers. These are given out in blocks by the not-for-profit GS1, and assigned to items by the users. Each one is a unique product. But there also ways, like code 128, of having barcodes made of letters.
Barcodes have even had a cultural impact.
They are an emblem on T-shirts, and are used as a symbol of capitalism or loss of identity by protesters.
People even have barcode tattoos. "We've started seeing them the last few years," says Neil Dalleywater, editor of Skin Deep tattoo magazine. "Particularly on the back of the neck."
Despite their connotations of mass production, they are a unique, personalised badge for those who get them, he says, depicting a birthday or other significant number.
Tattooist Lal Hardy of New Wave Tattoos, say barcodes are so hard to ink onto skin that most artists strongly advise people to avoid them.
"We refuse to do them. It is very difficult to do parallel lines. Most people want them fairly small - after a period of time they spread."
And some might say this check on the ubiquity of the barcode is not necessarily a bad thing.
Send us your comments using the form below.
I have had my national insurance number as a barcode tattooed on my arm for 10 years. I once met a girl who had a similar barcode on her arm and when i asked her what it was she said,"um, dunno I think it's a loaf of bread or something"!
Scott Tobin, Sidmouth
I use barcodes constantly in my day to day work. My job... I'm not a checkout girl but a laboratory worker for the blood service. We use barcodes to make sure all our blood products are accounted for during processing, testing and distribution but at the bedside it ultimately comes down to someone reading a label to ensure the right blood is given to the right person. Looks like not even we trust the barcode completely.
I remember my first trip to the USA in 1979. As a kid I was intrigued by why every product had a bar code on it. I never saw them in England. Barcodes are one of many technological inventions that make us richer. Because it is faster to scan an item then to key in the price at a cash register, it means fewer check out staff which eventually means lower prices. Any cost saving due to technological advances must be passed on to the consumer because of competition (assuming that there is competition).
Eugene Merrett, London, England
I have a friend who was afraid that the barcode was a sign of the coming of evil. The barcode is typically broken into two sections with the barcode symbol for "6" acting as the three dividers (one at each end and one in the middle) and thus, "666" was on every barcode (it seemed). The book of Revelation doesn't help when it says you can't buy or sell without the mark of the beast (13:17-18) but then again... maybe those self-serve checkouts are the embodiment of evil.
Reading this I remembered back to my first job, age 13 (in 1995), working at a pet shop, and the gentle steady rhythm of stamping price labels onto hamster food. I though I would be one of the younger people to have experienced this. Then I realised I was watching a store assistant on Gap dutifully re-pricing sale items with an old fashioned gun yesterday, and getting annoyed at how the silly little stickers had fallen off so many garments. Although barcodes are great for stock and re-pricing purposes, surely the next step is advance which allows items on the shelf to display their new price during sales? No more of that getting to the till and finding it's actually £2 joy, but also none of that queuing to find the sale price only to discover it's still £30! Also, barcodes are fantastic for using calorie counters on smartphones if you get the right app, and I'd seriously consider a barcode wedding ring marking out the date...
Barcodes on cows? Check out DEFRA's British Cattle Movement Service!
Chris Reynell, Longstock, UK
There was a TV show in 2000-2002 called Dark Angel. Set in the USA in a dystopian 2019, any main character who was genetically modified (to become a super-soldier) had a barcode on the back of their neck as identification.
I work in a library, a place where the barcode has made a big difference over the past 30 years. The ability to scan cards and books to make the operation of basic tasks quick and easy is so much better than the old way, using filing cards. I also used to work in a DVD rental store. Again barcodes made it all seamless and in some ways more fool-proof. Those lines and spaces are brilliant.
Luke Cranenburgh, London
If there is a problem with a supermarket's daily data then it automatically predicts restocking based on sales on the same day of the previous week. After such a failure a branch received an unexpectedly large consignment of lemons on a Tuesday - a week after Shrove Tuesday.
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