More than five billion bar codes are scanned each day worldwide, and that number is increasing rapidly as the codes’ uses extend beyond the checkout counter. Although bar codes are fast becoming ubiquitous, Norman Joseph Woodland, who patented the idea of a linear bar-code system in 1952, had to wait more than 20 years to see the system in action. His coinventor, Bernard Silver, didn’t live to see it at all.
In 1948 the president of a grocery store chain in Philadelphia implored a dean at Drexel Institute of Technology to develop an automated checkout system. Silver, a graduate student, overheard the conversation and was instantly intrigued. Woodland, a friend and fellow grad student, shared Silver’s enthusiasm, and the two devoted themselves to the effort. In late 1949 they applied to patent a system that drew on aspects of Morse code and movie sound systems. Similar to today’s bar code scanners, their device used a light source and a photosensitive reader to translate data encoded in linear symbols. But because it required a blindingly bright, extremely hot 500-watt incandescent light bulb and a large, unwieldy vacuum-tube photomultiplier to process data, the invention wasn’t appealing for widespread use in grocery stores.
The two inventors were undeterred. Their patent was granted in 1952, and Woodland hoped to continue to improve the system at IBM, where he had recently taken a job. The company expressed only limited interest in Woodland and Silver’s work, and after several years the two sold the patent to Philco and turned their attentions elsewhere. Silver died in 1962.
In the late 1960s just as Woodland and Silver’s patent expired, several nascent technologies converged to make product-scanning systems feasible. The laser could provide an intense, low-heat light source, and processors were becoming small and inexpensive enough for commercial use. Several companies demonstrated prototype systems, causing quite a stir in the grocery industry. Ten grocery manufacturers and retailers formed a committee in 1970 to choose a standard for encoding product data.
By then, IBM wanted in on the action, and it brought in Woodland, who was still at the company, to help launch a bar code research effort. In the spring of 1973 the standards committee chose IBM’s symbol, designed by engineer George J. Laurer, over those from six other companies. On June 26, 1974, in Troy, OH, a package of Wrigley’s chewing gum was the first item scanned using the Universal Product Code.
Keep Reading
Most Popular
Large language models can do jaw-dropping things. But nobody knows exactly why.
And that's a problem. Figuring it out is one of the biggest scientific puzzles of our time and a crucial step towards controlling more powerful future models.
The problem with plug-in hybrids? Their drivers.
Plug-in hybrids are often sold as a transition to EVs, but new data from Europe shows we’re still underestimating the emissions they produce.
How scientists traced a mysterious covid case back to six toilets
When wastewater surveillance turns into a hunt for a single infected individual, the ethics get tricky.
Google DeepMind’s new generative model makes Super Mario–like games from scratch
Genie learns how to control games by watching hours and hours of video. It could help train next-gen robots too.
Stay connected
Get the latest updates from
MIT Technology Review
Discover special offers, top stories, upcoming events, and more.