Picture the keypad of a telephone and calculator side by side. Can you see the subtle difference between the two without resorting to your smartphone? Don’t worry if you can’t recall the design. Most of us are so used to accepting the common interfaces that we tend to overlook the calculator’s inverted key sequence. A calculator has the 7–8–9 buttons at the top whereas a phone uses the 1–2–3 format.

Looking at the key arrangement, I was curious to learn when the system of using keys was introduced in the history of machines. The keyboard came about sometime between the first and second industrial revolutions (from 1820 to 1920). Some inventors had already begun experimenting with machines similar to pianos in the late 18th century.

However, it wasn’t until 1844 that a Frenchman by the name of Jean-Baptiste Schwilguć came up with the first working prototype of a key-driven calculator machine. This machine used the first numerical keyboard with a single row of keys that increased from 1 to 9 (Dalakov, 2018).

In all fairness, though, we have to mention two predecessors that could claim they invented the key-based interface. In 1834, Luigi Torchi reportedly showed a prototype of a wooden calculator, with a design similar to the typewriter. In 1822, author James White’s New Century of Inventions showed a key-based device with nine numeric keys. Neither one stood up to the test of time, nor no proof was given that they weren’t just fantasy (Durant, 2011).