Search notes:

JavaScript: NaN

NaN is a property of the global object. Its type is Number (typeof(NaN) returns "number").

<!DOCTYPE html>
<html>
<head>
  <meta content="text/html;charset=utf-8" http-equiv="Content-Type">
  <title>NaN</title>

  <script type="text/javascript">

    function main() {

      var out = document.getElementById('out');

      out.innerHTML += typeof(NaN)    + "<br>"; // number

      out.innerHTML += NaN + 5        + "<br>"; // NaN
      out.innerHTML += NaN + Infinity + "<br>"; // NaN
      out.innerHTML += NaN +'Foo'     + "<br>"; // NaNFoo

    }

  </script>

</head>
<body onload='main()';>
  <div id='out'>
  </div>
</body>
</html>

Github repository about-javascript, path: /objects/Global-Object/value-properties/Nan.html

JavaScript: NaN

See also