The first supermarket beep was a pack of chewing gum

That morning, at Marsh Supermarket in Troy, Ohio, they were debuting a strange invention: a laser reader wired to the till. The first customer laid a pack of Juicy Fruit gum on the belt. Beep. 67 cents. Modern shopping had just been born.

The barcode had existed on paper for decades: Joseph Woodland came up with it in 1949, drawing lines in the sand on a beach while thinking about Morse code — dots and dashes stretched downward. But it took the laser and cheap computers for those stripes to come alive.

Nobody ever chewed that pack of gum: it ended up on display at the Smithsonian, like the first word of a new language.

Today, barcodes are scanned more than 6 billion times a day. Every beep at every checkout on the planet is an echo of that 67-cent pack of gum.