Digging up a very old blog entry from http://www.456bereastreet.com/archive/200408/sizing_monospaced_fonts/, the question is asked, “What’s up with the different font sizes when the monospace font family is used?” The answer, as usual with Web browsers, is pretty interesting (which is browser developer-speak for “insanely confusing”).

FOUC stands for Flash of Unstyled Content.