What is typeof(NaN) in Javascript? [duplicate]

Question

I just happen to stumble upon a code which checks the typeof of a varable passed to it just like this.

function myNaN(b){

  if(typeof(b) == 'number'){
    // execute some code
  }

}

Whenever I call this function it works fine and passes the if condition if number is being passed.

However when I pass a NaN (which is the output of some other function) to this function the if condition returns true.

My question is it correct that typeof(NaN) == 'number' ? If so, why? Isn't it confusing?

Just try running console.log(typeof(NaN)); in browser console to see what I mean.

Answer 1

Yes, typeof(NaN) is number. You can check if the value is NaN specifically using the function isNaN.

Answer 2

Why don't you use the: "isNan("1234")" function ? Here is some link if it helps: http://www.w3schools.com/jsref/jsref_isnan.asp