The Locksmith's Feel

Hold it in your hand for a moment. A standard pin-tumbler padlock — the kind on a gym locker, the kind on a storage unit, the kind on the front gate of a hundred ordinary places. It weighs maybe a hundred and fifty grams. Its body is brass or hardened steel. The keyway is a narrow slot no wider than your thumbnail. From the outside it is a closed object, a solid thing, a container whose entire purpose is to refuse you. A locksmith looks at the same object and sees an open conversation. Inside the lock body, behind the keyway, is a plug — a small cylindrical core that can rotate once the right key is inserted. Running through the plug and through the housing above it are a series of vertical shafts, usually five or six of them. Into each shaft, two pins are stacked: a driver pin on top, a key pin on the bottom. Springs push the driver pins down.