In 1949, Joe Woodland drew the world's first bar code in the sand of Miami's beaches. According to Smithsonian, Woodland was inspired by his Boy Scouts days when he learned Morse code: "I remember I was thinking about dots and dashes when I poked my four fingers into the sand and, for whatever reason — I didn't know — I pulled my hand toward me and I had four lines. I said 'Golly! Now I have four lines and they could be wide lines and narrow lines, instead of dots and dashes.'"

His goal was to create something that could be printed on groceries to streamline the checkout process, thereby shortening supermarket queues. Woodland realized that by varying the thickness of black and white lines, different numbers could be "read" with a light. Woodland's original barcodes were created as circular bullseye shapes, but the printers tended to smear the ink.

When IBM bought Woodland's patent, an engineer named George Laurer fixed this issue by switching to the vertical lines we see today, which are organized in three sections. The first part of a barcode tells you the country where it was issued, the next part reveals the manufacturer of the product, and the final part of the barcode identifies the product itself. His team originally used a 500-watt incandescent bulb to read his code, before one of their research scientists, Theodore Maiman, created a super bright light called a "laser."

The first real-life scan of a barcode happened at a Marsh supermarket in Troy, Ohio on a pack of Wrigley's Juicy Fruit gum. Why gum? Because it's small: no one was sure a bar code would fit on something so tiny, and Wrigley earned a place in history by making it happen.

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