Door locks-hardware have actually been around for quite a long time. Some person with something very precious to protect came up with a basic wooden pin-lock mechanism around 6000 years ago in Mesopotamia. That lock was opened with a wooden key. What’s surprising is the mechanics haven’t really changed much in all that time. Most homes today still use a pin-lock cylinder mechanism just like that only in metal. Ours open with a metal key. If you are like most homeowners, you probably have a key for your front door.