In the mid-1850s, at the Palace of Khorsabad in Iraq, archaeologists found a simple lock and key system which dated back to 4000 B.C.E. The lock used pins of different lengths to secure the door, and the owner would then use a key which pushed the pins of the lock, allowing entry. In this way, you could protect valuables without constant monitoring. From our earliest beginnings, humans have been trying to protect valuables from theft and destruction.
