The first barcode scanned on a product at a checkout was in 1974. The item was a 10-pack of Wrigley's Juicy Fruit chewing gum, scanned at a Marsh supermarket in Troy, Ohio, on June 26, 1974.
The barcode was a Universal Product Code, or UPC. Grocery manufacturers and retailers had developed the standardized system to speed checkout, improve inventory tracking, and reduce pricing errors. The first scan took place at 8:01 a.m., and the cash register recorded the gum's price as 67 cents.
The event was a carefully planned test of new retail technology, not an accidental discovery. The shopping cart contained other barcoded products, but the gum was the first item lifted over the scanner. A replica package is now held by the Smithsonian's National Museum of American History.
A common mix-up is confusing the invention of barcodes with the first retail scan. Early barcode concepts existed decades earlier, including a 1949 patent by Norman Woodland and Bernard Silver. The milestone in this question refers specifically to the first UPC product scanned at a supermarket checkout.