Source : Free On-Line Dictionary of Computing

scan design
     
         (Or "Scan-In, Scan-Out") A electronic circuit
        design technique which aims to increase the controllability
        and observability of a digital {logic circuit} by
        incorporating special "{scan register}s" into the circuit so
        that they form a {scan path}.
     
        Some of the more common types of scan design include the
        {multiplexed register} designs and {level-sensitive scan
        design} (LSSD) used extensively by {IBM}.  {Boundary scan} can
        be used alone or in combination with either of the above
        techniques.
     
        ["Digital Systems Testing and Testable Design" by Abramovici,
        Breuer, and Friedman, ISBN 0-7167-8179-4].
     
        ["Design of Testable Logic Circuits" by R.G. Bennetts,
        (Brunel/Southhampton Universities), ISBN 0-201-14403-4].
     
        (1995-02-23)