This item is from the Yet Another Enhanced IDE/Fast-ATA/ATA-2 FAQ, by John Wehman and Peter den Haan with numerous contributions by others. (v1.92).
S.M.A.R.T. or Self Monitoring Analysis and Reporting Technology allows the drive to report about certain types of degradation or impending failure. This allows the operating system to take the necessary precautions and warn the user. The OEM release 2 of Win95 and the next OS/2 version (Merlin) will be SMART aware. The utility of this feature will initially be quite limited, though, because many failure modes (including the infamous Monday morning failure) can't be sensed in advance.
At present only few utilities exist to examine the S.M.A.R.T. status of a drive. These include Micro House EZ-S.M.A.R.T. and Symantec S.M.A.R.T. Doctor.