Infocom

Infocom n.  A now-legendary games company, active from 1979 to
   1989, that commercialized the MDL parser technology used for
   {Zork} to produce a line of text adventure games that remain
   favorites among hackers.  Infocom's games were intelligent, funny,
   witty, erudite, irreverent, challenging, satirical, and most
   thoroughly hackish in spirit.  The physical game packages from
   Infocom are now prized collector's items.  The software,
   thankfully, is still extant; Infocom games were written in a kind
   of P-code and distributed with a P-code interpreter core, and
   freeware emulators for that interpreter have been written to permit
   the P-code to be run on platforms the games never originally
   graced.