the.com/monospace
every letter gets the same elbow room, whether it's an i or a w.
means a typeface where each character occupies identical horizontal width, unlike proportional fonts that give a skinny i less space than a fat m.
from born from the mechanical constraints of typewriters, where a single carriage moved a fixed distance per keystroke no matter what letter you struck, so type designers just built fonts to match the machine.
typewriter legacycourier was modeled directly on typewriter output
code readabilityaligned columns make indentation and diffs scannable
terminal defaultnearly every text editor ships one as default font
for instance
menlo — apple's default terminal and xcode font since 2009
consolas — microsoft's cleartype-optimized coding font, shipped since vista
ibm plex mono — ibm's 2017 open-source rebrand of its typographic identity