A hackish (and especially MIT) tradition is to choose acronyms/abbreviations that refer humorously to themselves or to other acronyms/abbreviations. The original of the breed may have been TINT (“TINT Is Not TECO”). The classic examples were two MIT editors called EINE (“EINE Is Not EMACS”) and ZWEI (“ZWEI Was EINE Initially”). More recently, there is a Scheme compiler called LIAR (Liar Imitates Apply Recursively), and GNU (q.v., sense 1) stands for “GNU's Not Unix!” — and a company with the name Cygnus, which expands to “Cygnus, Your GNU Support” (though Cygnus people say this is a backronym). The GNU recursive acronym may have been patterned on XINU, “XINU Is Not Unix” — a particularly nice example because it is a mirror image, a backronym, and a recursive acronym. See also mung, EMACS.