In Boolean algebra, the logical complement or negation of a Boolean value is the opposite value, given by the following truth table:

        A | -A
        --+---
        T | F
        F | T

-A is also written as A with a bar over it or with a small vertical line hanging from the right-hand end of the "-" (LaTeX \neg) or as A'. In the C programming language, it is !A and in digital circuit design, /A.