My keys are the wearables that I have always in my pocket. Or at least I try to. The key, as a devise that operates a lock is found in different forms, however, the most common type nowadays is the pin tumbler key, that operates the pin tumbler lock, or Yale lock, invented in 1861 and named after its manufacturers. To unlock a Yale lock, a flat key is inserted into the key hole, it passes under the downward-pressing pin tumblers and raises them to a specific point at which the plug can rotate. At a later patent, in 1865, Yale describes the key as a ‘thin slip of steel properly shaped to bring the lines of division between the tumblers into the same line’. The invention of the Yale lock is an important characteristic of the changes that occurred in the mid nineteenth century in the United States and the transition to the mechanization. Yale describes his invention as a ‘post-office drawer lock’ and according to Giedion, ‘the development of the fireproof safe and of bank locks coincides with the rise of industry, large scale banking and finance, the growth of the stock exchange, expanding wealth, the multiplication of fortunes’(Giedion, 1948).

Reference: Giedion, S. (1948). Mechanization takes command : a contribution to anonymous history . New York: Oxford University Press.