A monospaced font is suitable for typesetting computer programs since each character has precisely the same width — allowing that successive rows of glyphs sit directly below related rows. Courier is an example however there are nicer looking monospace fonts than Courier (which has oversize serifs), that still remain distinct from the text fonts like Times and Helvetica. A good one is OCR-B, designed by Adrian Frutiger as a monospaced version of his Univers more legible to OCR devices. It is clunky but ubiquitous. Note that monospaced fonts are less economical on space than proportional fonts.
Typeface category, letters are of equal width, resembles typewriter type. Since each character occupies the same horizontal space these may be described in CPI (characters per inch). An example is Courier typeface.
In typography, descriptive of characters of a typeface all having the same width. The lowercase “i” and “m”--which would have different widths in proportional width typefaces--are identical in monospaced typefaces.