Determine if a value is NaN. This robust is-nan package offers a reliable check, unlike the built-in isNaN() function which suffers from unexpected type coercion. It returns true only if the input is truly NaN, preventing false positives caused by strings or other non-numeric values. Useful for validating numerical data and ensuring consistent behavior across different JavaScript environments. This tiny library is essential for avoiding unexpected type coercion issues related to NaN checks.