History of mechanical locks started over 6 thousand years ago in Ancient Egypt, where locksmith first managed to create simple but effective pin tumbler lock that was made entirely from wood. It consisted of the wooden post that was affixed to the door and a horizontal bolt that slid into the post. This bolt had set of openings which were filled with pins. Specially designed large and heavy wooden key was shaped like a modern toothbrush with pegs that corresponded to the holes and pins in the lock. This key could be inserted into the opening and lifted, which would move the pins and allow security bolt to be moved.