ifIf a value is too large to be stored it can be assigned a special value indicating that overflow has occurred and then have all successive operationoperations return this flag value. Such values are sometimes referred to as [[NaN]], for "not a number". This is useful so that the problem can be checked for once at the end of a long calculation rather than after each step. This is often supported in floating-point hardware called [[floating point unit|FPUs]].
