Monospaced font

A monospaced font, also called a fixed-pitch, fixed-width, or non-proportional font, is a font whose letters and characters each occupy the same amount of horizontal space. This contrasts with variable-width fonts, where the letters and spacings have different widths. For example, the two high-use letters "I" and "E" do not need the same footprint. Both letters differ in center-to-next-letter edge (and center-to-center) spacing distance needs (margins) in variable width fonts. The variable that changes is offset from what would otherwise be monospaced centering. In a modern proportional font, every dimension can be scaled and changed, but such sizing mathematically must still maintain monospacing or variable spacing.

Note that this article generally assumes Western (Latin-based, Cyrillic, or Greek) writing systems. East Asian rules of typography, for example, require CJK fonts to be always monospaced at least as far as the main characters for writing words (i.e. not punctuation) are concerned. Other scripts vary in their use of monospaced fonts.

The first monospaced Western typefaces were designed for typewriters, which could only move the same distance forward with each letter typed—simply because all striker arms on a typewriter are physically the same width or won't align and pass through the positioning gap. This also later meant that monospaced fonts need not be hand-typeset (since Gutenberg, using physical blocks) and electric motorized cam driven auto typesetters could be manufactured. Monospace fonts being the same size and spacing, unlike variable width fonts and were and are arguably, easier to deal with since everything is uniformly spaced.

Examples of monospaced fonts include Courier, Courier New, Lucida Console, Monaco, and Consolas.

Monospaced fonts were widely used in early computers and computer terminals, which often had extremely limited graphical capabilities. Hardware implementation was simplified by using a text mode where the screen layout was addressed as a regular grid of tiles, each of which could be set to display a character by indexing into the hardware's character map. Some systems allowed colored text to be displayed by varying the foreground and background color for each tile. Other effects included reverse video and blinking text. Nevertheless, these early systems were typically limited to a single console font.

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