[1] : WordNet (r) 2.0

checksum
     n : a digit representing the sum of the digits in an instance of
         digital data; used to check whether errors have occurred
         in transmission or storage

[2] : The Free On-line Dictionary of Computing (27 SEP 03)

checksum
     
         a computed value which depends on
        the contents of a block of data and which is transmitted or
        stored along with the data in order to detect corruption of
        the data.  the receiving system recomputes the checksum based
        upon the received data and compares this value with the one
        sent with the data.  if the two values are the same, the
        receiver has some confidence that the data was received
        correctly.
     
        the checksum may be 8 bits modulo 256 sum, 16, 32, or some
        other size.  it is computed by summing the bytes or words of
        the data block ignoring overflow.  the checksum may be
        negated so that the total of the data words plus the checksum
        is zero.
     
        internet packets use a 32-bit checksum.
     
        see also digital signature, cyclic redundancy check.
     
        1996-03-01
     
     
see also:
overflow internet packets digital signature cyclic redundancy check 

Checksum >> C Words
Checksum, definition of term: Checksum
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