bit map Definition bit map A bit map is a string of bits in which each bit has a symbolic, rather than numeric, value. ***** See Also ***** bit, byte, definitions The C Programming Language, ed. 2, page 136 ***** Notes ***** C permits the manipulation of bits within a byte through the use of bit-field routines. These generate code rather than calls to routines. Bit fields are generally less efficient than masking because they always generate masking and shifting. COHERENT Lexicon Page 1