Keys – a basic but essential technology. They’re so ingrained in our lives that we tend to take them for granted, unless of course we lose them! The earliest key and lock system dates back to 4000 B.C. at the Palace of Khorsabad, located in modern-day Iraq. It was a pin lock system and entirely made of wood. The ancient Egyptians then updated the design to utilize brass in the pins and popularized the use of lock and key in architecture. The Romans further innovated on the concept and created the first small-scale locks and keys for securing chests and drawers. It wasn’t until the Middle Ages that English craftsmen first made all-metal warded locks and keys – these would have resembled the fancy old castle keys often seen in movies. In 1861, Linus Yale Jr. invented the flat grooved key with notches – this type of key is still in use today and is probably what you use to get through your front door every day! And while many companies are currently working toward a keyless future using modern technology, physical keys are probably not going anywhere anytime soon.