Mono Space Font

A mono-spaced font, also called a fixed-width or non-proportional font, is a font whose letters occupy the same amount of space. This contrasts to variable-width fonts, where the letters differ in size to one another.

The first mono-spaced typefaces were designed for typewriters, which could only move the same distance forward with each letter typed. This also meant that mono-spaced fonts need not be typeset like variable width fonts and were, arguably, easier to deal with.
DocFamily supports various mono-space fonts such as Courier or Courier New.