holy wars n. [from {Usenet}, but may predate it; common] n. {flame
   war}s over {religious issues}. The paper by Danny Cohen that popularized
   the terms {big-endian} and {little-endian} in connection with the
   LSB-first/MSB-first controversy was entitled "On Holy Wars and a Plea
   for Peace".

   Great holy wars of the past have included {{ITS}} vs. {{Unix}},
   {{Unix}} vs. {VMS}, {BSD} Unix vs. System V, {C} vs. {{Pascal}}, {C} vs.
   FORTRAN, etc. In the year 2000, popular favorites of the day are KDE vs,
   GNOME, vim vs. elvis, Linux vs. [Free|Net|Open]BSD. Hardy perennials
   include {EMACS} vs. {vi}, my personal computer vs. everyone else's
   personal computer, ad nauseam. The characteristic that distinguishes
   holy wars from normal technical disputes is that in a holy war most of
   the participants spend their time trying to pass off personal value
   choices and cultural attachments as objective technical evaluations.
   This happens precisely because in a true holy war, the actual
   substantive differences between the sides are relatively minor. See also
   {theology}.


Source: The Jargon File