official production system

from The Free On-line Dictionary of Computing (8 July 2008)

Official Production System

   <language> (OPS) The first {production system} (i.e. rule
   based) programming language, developed at {CMU} in 1970 and
   used for building {expert systems}.  OPS was originally
   written in {Franz Lisp} and later ported to other {LISP}
   dialects.

   (2003-04-05)