The Free On-line Dictionary of Computing (30 December 2018):

FTW

    An ambiguous acronym which might stand for any of "For
   The Win" (the thing just referred to will help you succeed),
   "Forever Two Wheels" (biker slang), WTF backwards, "Fuck The
   World", "Fuck This War", "Fun To Watch" or something else.

   (2008-09-12)