NAND Gate Definition/Meaning:
An electronic logic gate whose output is logic 0 (false) only when
all (two or more) inputs are logic 1 (true),
otherwise it is logic 1. It thus implements the logical NAND operation and has
the same truth table. The diagram shows the usual circuit symbol of a two-input
gate (which implies by the small circle that it is equivalent to an
whose output has been inverted) and the associated truth table.