Pay attention: on your computer or smartphone keyboard, 0 is found after 9 and never before 1. Realizing this apparent strangeness spontaneously raises a question: Why on the keyboard does 0 come after 9 and not before 1? The answer has its roots in the history of typewriters. This choice, apparently counterintuitive, was not in fact dictated by modern practical reasons, but rather by technical constraints that date back to the ancestor of today’s keyboard for PCs and smartphones: the typewriter! When at end of the 19th century began to spread first machines to write, these they did not include keys dedicated to the digits 0 and 1 because they used a capital O and a capital I insteadmaking them cheaper and easier to use.
When the 0 button was subsequently introduced, it was placed next to the 9 to maintain a visually logical sequence, otherwise avoiding a visual anomaly that would have stood out more easily to the eye, given by the presence of the sequence 0, 2, 3, etc. The key dedicated to the digit 1, in fact, only arrived in the 1950s and, despite this, the layout was not modified and the 0 was left after the 9. This layout was then also inherited by PC keyboards first, and by keyboards smartphone and tablet software after.
The 0 and 1 keys were not initially considered
The first commercially successful typewriter, the Sholes and Gliddenalso known as Remington No. 1was introduced in 1873. This device only printed capital letters and It did not have dedicated keys for the numbers 0 and 1. Why? Simply because they weren’t deemed necessary: typists used a capital O to represent 0 and a capital I to represent 1. This choice was practicable thanks to the type of font used, where these symbols were identical. Reducing the number of keys not only made typewriters cheaper to produce, but also simplified their internal mechanisms, which were quite complex at the time.
When, in 1878the model Remington No. 2 introduced the Shift key to switch between uppercase and lowercase letters, the keyboard layout began to evolve. However, even in that model the 0 and 1 keys continued to be missingletting the capital O and capital I do their double role. Only later, with a later revision of the Remington No. 2, the 0 key was added. The choice to place it next to the 9 on the numeric line derived from aesthetic and logical considerations: placing the 0 at the beginning of the line would have created the sequence 0, 2, 3, 4, 5, etc., which appeared anomalous without the 1 between 0 and 2.
There decision to add key 1 it arrived much later, around 1950swhen typewriter and computer keyboards began to standardize. Despite that, no one felt the need to rearrange the entire number layout to put the 0 before the 1. The reason? The habit now rooted among users and the inertia of producers, who preferred not to alter a system already consolidated and well accepted by the public.
Other “missing” keys in early typewriters
In addition to the 0 position, early typewriters also omitted other symbols today considered fundamental, such as the exclamation point. This character, for example, came created by combining a period and an apostrophe: The typist would type the period, use the backspace key to move the cursor back, and then add the apostrophe. A similar procedure was adopted for symbols such as plus or equal, which were obtained by combining other characters. Also the backspace key itself had a different function than today: it didn’t help to erasebut rather to move the cursor back without changing the text. All these peculiarities derived from the need to limit the number of keys and from the rudimentary technology available at the time.
