The logical connective combining two statements, truth values, or formulas P and Q in such a way that the outcome is true only if both P and Q are true; otherwise the outcome is false (see table). The AND operation is usually denoted by ∧, and occasionally by, or by juxtaposition, as in PQ. It is one of the dyadic operations of Boolean algebra and is both commutative and associative.

When implemented as a basic machine operation on computers, the AND operation is usually generalized to operate on complete words. Then the operation described above is applied to the corresponding bits in each word. In this context AND is often used for masking purposes, i.e. to select parts of words, such as the address field.

AND operation. Truth table for AND operation