exclusive-or

In logical operations, the exclusive disjunction, also called exclusive or, (symbolized XOR or EOR), is a type of logical disjunction on two operands that results in a value of "true" if and only if exactly one of the operands has a value of "true." Put differently, exclusive disjunction is a logical operation on two logical values, typically the values of two propositions, that produces a value of true just in cases where the truth value of the operands differ.
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