Locksmithing began as the science and art of making and defeating locks. A lock is a mechanism that secures buildings, rooms, cabinets, objects, or other storage facilities. A key is often used to open a lock. Means of opening a lock may include a security token or two-factor authentication for greater security, such as requiring both something a person knows (a combination) and something they have (a key or keycard).
The oldest known lock is approximately 4,000 years old and was of Egyptian make. The earliest known key-based lock was built during the Assyrian Empire in Khorsabad near Nineveh about 704 BC. It may have been found in the ruins of the Emperor Sargon II's palace in Khorsabad. It used the same pin tumbler principle employed by many modern locks.
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