Source : Free On-Line Dictionary of Computing

Adaptive Digital Pulse Code Modulation
     
         (ADPCM) A {compression} technique which
        records only the difference between samples and adjusts the
        coding scale dynamically to accomodate large and small
        differences.  ADPCM is simple to implement, but introduces
        much {noise}.
     
        [Used where?  Does the {Sony} minidisk use ADPCM or {ATRAC}?]
     
        (1998-12-10)