In the early 1960s, Scottish engineer James Goodfellow was given a problem to solve. A colleague had invented a way to insert a card into a machine and get money out. Goodfellow’s task was to figure out a way to ensure that only the card’s legitimate owner could use these new “ATM” machines to obtain cash. So he created the personal identification number, what we call the PIN, the most secure implementation of card access the world had ever seen. Goodfellow was awarded the patent on the PIN and, later, Queen Elizabeth II awarded him the Order of the British Empire.