NOR

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NOR

[nȯr]
(mathematics)
A logic operator having the property that if P, Q, R, … are statements, then the NOR of P, Q, R, … is true if all statements are false, false if at least one statement is true. Derived from NOT-OR. Also known as Peirce stroke relationship.

NOR

Not OR.

The Boolean function which is true if none of its inputs are true and false otherwise, the logical complement of inclusive OR. The binary (two-input) NOR function can be defined (written as an infix operator):

A NOR B = NOT (A OR B) = (NOT A) AND (NOT B)

Its truth table is:

A | B | A NOR B --+---+--------- F | F | T F | T | F T | F | F T | T | F

NOR, like NAND, forms a complete set of Boolean functions on its own since it can be used to make NOT, AND, OR and any other Boolean function:

NOT A = A NOR A

A OR B = NOT (A NOR B)

A AND B = (NOT A) NOR (NOT B)

NOR

(Not OR) A Boolean logic operation that is true if all inputs are false, and false if any input is true. A NOR gate is constructed of an OR gate followed by a NOT gate.

An exclusive NOR (XNOR) is true if both inputs are the same. An XNOR is constructed of multiple NOR gates. See Boolean logic, flash memory and NAND flash.