KEYS have been around for a long time. The earliest, made from wood, date back to the ancient Egyptians. The Romans improved them by making them from metal. But there, more or less, they have stayed.
A key is still, basically, a piece of metal sporting a series of grooves, teeth and indentations which, when inserted into a keyway, line up to move pins and levers to lock or unlock a mechanism.
Such keys are made with conventional manufacturing techniques, such as cutting and stamping. But now there is a new way, in the form of 3D printing, to craft metal objects. And keys are about to succumb to it, to the great benefit of keyholders.
A 3D printer successively adds layers of material to the object being created. It can thus make something from the inside out.