Source : Free On-Line Dictionary of Computing

System Management Mode
     
         (SMM) A reduced power consumption state provided by
        some {Intel} {microprocessors}.  When a {CPU} enters SMM it
        saves its current state in a special area of {static RAM}
        called SMRAM (System Management {RAM}) and then runs a
        program, also stored in SMRAM, the SMM handler.
     
        SMM is implemented in all {Intel} "SL" suffixed CPUs.  In June
        1993, Intel announced it was discontinuing its SL range and
        instead making all its current processors SL enhanced.
     
        See also {Auto Idle}.
     
        (1994-11-09)