Why does typeof NaN return 'number'?

Question

Just out of curiosity.

It doesn\'t seem very logical that typeof NaN is number. Just like NaN === NaN or NaN == NaN returning

Answer 1

If using jQuery, I prefer isNumeric over checking the type:

console.log($.isNumeric(NaN));  // returns false
console.log($.type(NaN));       // returns number

http://api.jquery.com/jQuery.isNumeric/