A Pack of Wrigley's Gum Was Scanned at 8:01 a.m. on June 26, 1974. That Item Is Now in the Smithsonian.
At 8:01 a.m. on June 26, 1974, Sharon Buchanan, a checkout operator at the Marsh Supermarket in Troy, Ohio, scanned a 10-pack of Wrigley's Juicy Fruit chewing gum. The scanner beeped. The price appeared on the screen. The transaction took seconds. That pack of gum, now in the collection of the Smithsonian Institution's National Museum of American History, was the first item in history sold using a barcode.
The barcode had taken 25 years to get there.
In 1949, a graduate student named Joe Woodland was sitting on Miami Beach, frustrated with checkout bottlenecks at supermarkets. He had been working on the problem with a colleague, Bernard Silver, after a chain store executive had asked the Drexel University engineering department to find a way to automatically read product information at checkout. As Woodland sat in the sand, he drew his fingers through it, creating a series of lines. The connection came to him: Morse code, adapted for visual scanning. Dots and dashes became thick and thin lines. Woodland and Silver filed their patent application in October 1949 and received US Patent 2,612,994 in October 1952.
The initial design used concentric circles in a bull's-eye pattern rather than stripes. The circle geometry meant the barcode could be read in any orientation, which was an advantage for checkout scanners that needed to work regardless of how a cashier held an item. The design was conceptually sound but had a manufacturing problem: the circular pattern was difficult to print with the ink and paper technology of the early 1950s, and smudging made accurate reads unreliable. The patent sat commercially unused.
George Laurer and the Rectangle That Won
The modern barcode's rectangular form emerged through an industry-organized competition in the early 1970s. Grocery chains, manufacturers, and trade associations had been working for years on standardizing automatic checkout, operating through a body that would become the Uniform Code Council. In 1973, the committee issued a formal invitation for barcode design proposals.
IBM engineer George Laurer submitted his design late in the process, nearly past the deadline. His modification of Woodland's concept replaced the concentric circles with vertical stripes arranged in a rectangle. The linear stripe geometry was dramatically easier to print accurately with the flexographic printing common on product packaging, and horizontal scanner lasers could read it as a product moved across a flat surface. Laurer's design was selected in April 1973 as the Universal Product Code standard.
The UPC barcode uses 12 digits. The first digit is a number system character that indicates the product category. Digits 2 through 6 identify the manufacturer, assigned by the Uniform Code Council. Digits 7 through 11 identify the specific product, assigned by the manufacturer. The twelfth digit is a check digit calculated from the preceding eleven to catch scanning errors. The check digit calculation uses alternating weights of 1 and 3: multiply odd-position digits by 1 and even-position digits by 3, sum all results, and the check digit is whatever value makes the total a multiple of 10.
The laser scanner that actually reads the barcode was developed at the same time. The first operational system, installed at the Marsh Supermarket in 1974, used equipment from NCR Corporation and Spectra-Physics, with the IBM scanner ultimately being the one that performed the first commercial scan. The scanner projects a laser beam that reflects differently off the dark bars and white spaces of the barcode, converting the pattern to an electrical signal that the reader decodes into the digit sequence.
The EAN Extension to Europe
The Universal Product Code was a 12-digit American standard. When European countries began adopting barcode scanning in the mid-1970s, they needed a compatible but distinct system that could identify European manufacturers. The European Article Number, EAN, was adopted in 1976 as a 13-digit extension of UPC: EAN-13 adds a leading digit (the country code, assigned by the International Article Numbering Association) to the 12-digit UPC structure.
EAN-13 is backward compatible with UPC: a UPC barcode is technically an EAN with a leading zero. American scanners that read UPC can read EAN-13 if their software supports the 13-digit format. This compatibility was not guaranteed when EAN was adopted and required explicit engineering to achieve.
The International Article Numbering Association eventually became GS1, which now governs the assignment of company prefixes and the standards for barcodes globally. GS1 maintains the codes that identify manufacturers, ensuring no two companies share the same prefix within the system. A company seeking to barcode products for retail must obtain a GS1 company prefix, which currently requires membership in GS1 with annual fees that scale by revenue.
QR Codes: Two-Dimensional Information
The QR code was invented by Masahiro Hara and his team at Denso Wave, a Toyota subsidiary, in 1994. Hara designed it to track automotive parts in the Toyota production system, where traditional linear barcodes could not hold enough information to identify specific components in complex supply chains.
The innovation was encoding information in two dimensions rather than one. A linear barcode encodes information in the widths and spacings of vertical stripes along one axis. A QR code encodes information in a two-dimensional matrix of black and white squares, allowing it to hold several hundred times more data than a UPC barcode in a similar physical area. A QR code can store up to 3,000 alphanumeric characters, compared to UPC's 12 digits.
Denso Wave made the QR code specification publicly available and did not enforce its patents, which contributed to wide adoption. The three distinctive square markers in the corners of a QR code serve as position detection patterns, allowing the reader to determine the code's orientation and scale regardless of the viewing angle. This is why QR codes can be scanned from smartphones held at awkward angles or at varying distances.
QR code use expanded dramatically in the early 2010s as smartphone cameras became capable of reading them without dedicated hardware. The COVID-19 pandemic drove another expansion in 2020 and 2021, when restaurants and businesses replaced physical menus and forms with QR code links to digital alternatives, normalizing the format for consumers who had previously encountered it infrequently.
Conclusion
Linear barcodes for retail settled on UPC and EAN. Logistics, manufacturing, and healthcare settled largely on Code 128, a barcode symbology developed in 1981 by Ted Williams at Laserlight Systems. Code 128 can encode the full 128-character ASCII set rather than digits only, making it suitable for product codes that include letters, hyphens, and other characters common in part number systems.
Code 128 also achieves higher data density than UPC: it can encode more characters per unit of length, which matters when space on a shipping label is limited. The GS1-128 variant of Code 128 uses application identifiers, standardized two-digit codes in parentheses, to structure data fields within a single barcode: expiration date, batch number, serial number, and other supply chain information can all be encoded in one label.
A barcode generator creates the graphical representation of a barcode from a text input. It encodes the characters according to the chosen symbology's rules, computes the check digit, and renders the bars and spaces at the correct proportions for reliable scanning. The ToolHQ barcode generator supports UPC, EAN, Code 128, and QR codes, with output available as SVG or PNG.
Frequently Asked Questions
What barcode format should I use for retail products?
EAN-13 is used internationally for retail products. UPC-A is the North American standard. Both require a registered GS1 company prefix. For internal inventory tracking without retail scanner requirements, Code 128 or Code 39 work without registration.
What is the difference between UPC and EAN barcodes?
UPC-A has 12 digits and is the North American standard. EAN-13 has 13 digits and is used internationally. EAN-13 is backward compatible with UPC-A scanners. Most modern retail scanners read both.
Can I generate my own barcode numbers?
For internal use (inventory, assets, library books), you can generate any number sequence. For retail products sold in stores, you need a globally unique number from GS1, the organization that manages the UPC/EAN numbering system.
What is Code 128 used for?
Code 128 encodes all 128 ASCII characters and is widely used in shipping, warehouse management, and logistics. It is denser than Code 39 and does not require registration for use.