These boring sets of black and white lines can now be found on almost every single item bought from a shop.
At first glance, it seems hard to see how they possibly made any impact on the world, but they have fundamentally changed the way we shop.
Norman Woodland first developed an early form of the bar code in 1949 by combining ideas from movie soundtracks and Morse code to help him speed up store checkouts. They now allow stores to instantly access product details, prices and stock levels with the sweep of a laser.
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