A key is a device that is used to operate a lock (such as to lock or unlock it). A typical key is a small piece of metal consisting of two parts: the blade, which slides into the keyway of the lock and distinguishes between different keys, and the bow, which is left protruding so that torque can be applied by the user. A key is usually intended to operate one specific lock or a small number of locks that are keyed alike, so each lock requires a unique key. The key serves as a security token for access to the locked area; only persons having the correct key can open the lock and gain access.
History of locks and keys goes back for several thousand years, reaching the very first moments when modern human civilization established their reign and started developing sciences and technologies that enable birth and growth of our modern way of life. Even in those ancient times some 4000 years ago, people wanted the ability to safeguard their possessions and store them in places where nobody else can get access to them. For that purpose, engineers, designers and scientist created first examples of locks and keys. Originally created using wood and other easily accessible natural materials, locks and keys offered small manner of protection against theft or intrusion, but they (as well as complicated rope knots) at least provided clear indicator if someone tampered with the lock.
First models of wooden keys and locks originate from Ancient Egypt, where they first managed to take advantage from the technique of falling pins to control the movement of the security bolt. The bolt could be freed from locked position by inserting large and cumbersome wooden key into the lock, and manually lifting it upwards, displacing the pins that were held down by gravity. Roman age introduced brought many improvements upon original Egyptian designs, but the expensive nature of the locks, their inability to sustain large external forces and easy picking made them to be a symbol of wealth, influence and nobility. Small keys made from metals (iron, bronze, silver, gold) were often viewed as one of the most effective ways of publicly showing your wealth (only very rich people could afford to have personal safes or doors with locking mechanisms).
Over the last two hundred years, locksmiths, engenders and technicians have managed to transform locks from very expensive and unreliable protective devices into mass produced safeguarding devices that are commonly used by everyone. Learn more about locks and locksmiths here.
History of Keys
Today, keys are one of the most commonly manufactured metal objects in the entire world, enabling us to live in the modern civilization that has many of its features safeguarded and locked behind billions of locks. They are easy to manufacture, small enough to be carried and offer intuitive (though imperfect) way of operating mass produced lock that guard our physical properties such as cars, buildings, doors, safes and more.
History of keys started at the same moment when first locks appeared in ancient Babylon and Egypt, some 6 thousand years ago. These simple wooden devices used small pins which were hidden in a small opening near the bolt. By using wooden toothbrush-shaped key, Egyptians could lift those small pins and unlock the blot. Sadly, this design had several disadvantages – both lock and key were made from wood (material that is very susceptible to external brute-force attacks) and the key itself was very bulky and heavy. The oldest examples of these ancient locks were found in ruins of the Assyrian palace of Khorasabad, in a biblical city of Nineveh. Those locks mechanisms were dated to 704 BC.
The next evolution of keys came in Ancient Rome, whose engineers and inventors managed to greatly improve upon the designs of Egyptian wooden locks. Having keys—or anything worth locking up—was uncommon. So the key was as much a status symbol as a security device. Affluent Romans often kept their valuables in secure boxes within their households, and wore the keys as rings on their fingers. The practice had two benefits: It kept the key handy at all times, while signaling that the wearer was wealthy and important enough to have money and jewelry worth securing. By using iron and bronze, romans were able to create much stronger and smaller locks, with keys that we light enough to be carried on person. As far as their form of the keys was concerned, one great invention changed their look forever. Introduction of wards into locks shaped the keys from large flat structures with pins on their end to the look of what we call today is “Skeleton key” – simple cylindrical shaft that has one single, thin and rectangular tooth (or bit). This design continued to be used for 17 centuries after the fall of Roman Empire, receiving only minor update in their looks (during all that time locksmiths were more focused on deceiving the thieves or making their work more tedious than innovating new safeguarding mechanisms). Skeleton keys can be found even today in houses that were built before 1940s.
Modern “flat keys” were first introduced to the public in 1861, Linus Yale, Jr. He was inspired by the original 1840s pin-tumbler lock designed by his father, thus inventing and patenting a smaller flat key with serrated edges as well as pins of varying lengths within the lock itself, the same design of the pin-tumbler lock which still remains in use today. But using tumbler lock and more sophisticated way of regulating the pins, these flat keys become instant success across entire world. They were easy to manufacture, and thanks to invention of key cutting, easy to replicate in large numbers.
Today, majority of the locks in the world uses flat keys that activate mechanisms invented in 1800s – warded locks, lever tumbler locks and pin tumbler locks. Small amount of keys are based on magnetic signatures, which are most often used in public buildings (such as hotels), government facilities, scientific labs, and similar sensitive locations.