iff

The term "iff" is a contraction of "if and only if," a logical operator used in mathematics, logic, and computer science to express a bidirectional conditional statement. It indicates that two statements are equivalent, meaning that one statement is true if and only if the other statement is true.

In formal logic, "iff" is often denoted by the symbol "⇔" or "↔." For example, the statement "P iff Q" can be written as "P ⇔ Q," which means that P is true if and only if Q is true, and Q is true if and only if P is true.

The "iff" operator is fundamental in defining logical equivalence and is used in various contexts, such as in the definition of logical equivalence, in the construction of truth tables, and in the formulation of logical arguments. It is also commonly used in programming and algorithm design to specify conditions under which certain operations or functions should be executed.

In everyday language, "iff" is sometimes used informally to mean "if and only if," although its precise logical meaning is reserved for formal contexts. Understanding the concept of "iff" is essential for grasping more complex logical and mathematical concepts.