Answer: A Pack of Wrigley's Juice Fruit Gum
In the late 1940s, Bernard Silver, a graduate student at the Drexel Institute of Technology's Philadelphia, heard the president of a local grocery chain talking Dean of his department about his desire for a system that can easily encode product data and speed up the buying process. Silver was curious about the idea, told his friend Joe Woodland, and together they immediately started working on possible solutions.
After several false starts with various ideas like UV ink (too expensive and too fast to fade) they started focusing on a method that is inspired by the simplicity of Morse code. This system evolved over a year to an early stage of today's bar code ̵
The barcode as we know it today, the Universal Product Code (UPC), became widely known only after a series of retail tests commissioned by the National Association of Food Chains in the mid-1960s. Even then, the barcode only appeared after nearly a decade of testing on a commercial product.
Finally, the now ubiquitous barcode made its public debut. On June 26, 1974, at a Marshs supermarket in Troy, Ohio, one of the test labs used by the NAFC, Clyde Dawson purchased a multipack of Wrigley's Juicy Fruit chewing gum, which was scanned by cashier Sharon Buchanan. This chewing gum package sparked the commercialization and widespread introduction of the bar code and, a quarter of a century after its invention, brought the problem of the food chain president together with a viable solution. Wrigley's chewing gum bundle and receipt are permanently exhibited at the Smithsonian Institute.