John Shepherd-Barron. You probably don't recognize the name...but I guarantee the 84-year-old Scotsman has changed the way you live.
Shepherd-Barron's invention was inspired by chocolate vending machines. He is said to have come up with his idea after being locked out of his bank.
Today there are more than 1.7 million of what he invented around the globe.
Do you have any idea what it was? Shepherd-Barron, who died Saturday, is credited with inventing the world's first ATM.
And here's an interesting tidbit. Shepherd-Barron told the BBC he originally planned to make personal identification numbers six digits long, but cut the number to four after his wife complained that six was too many.