The NOT function indicates
logical negation/
complement. It can be represented by a number of notations: all of the following mean 'NOT F':
_
F = F' = !F = ~F
The bar is most commonly used in digital systems, the bang is most commonly used in programming languages.
The truth table for the NOT function is:
_
F | F
--+--
0 | 1
1 | 0
In digital circuits, this function can be implemented by an inverter, and via the magic inherent in mixed logic.
See also AND, OR, NAND, NOR, XOR, NXOR, DeMorgan's Laws, logic, boolean algebra.