The development of monospaced typefaces was from the limitation of mechanical typewriters from 1955. The original typewriting fonts were Slab Serif typeface but being monospaced because the characters hold an equal distance apart, which is the development of the font called ‘Courier.’ By then, most companies had their own Pica typeface, a monospaced font that fit ten characters to the inch as their standard.
In that manner, it was easier for the typist as when the typist pressed a key, the carriage moved the paper the same distance each time, so it was easier to return to a previous printing point to make corrections and do tabulation work. Because of this characteristic of monospaced font, they were not only the main preference of the typewriters, but it was also used for the early CRT screens, where characters were made from pixels in boxes that were all the same size.