JSFiddle - React, Tailwind, and code Playground

JavaScript

var a = "a";
document.write('"a" is ' + ((a instanceof String) ? '' : 'not ') + 'a String');
document.write('<br>');
var b = String("b");
document.write('String("b") is ' + ((b instanceof String) ? '' : 'not ') + 'a String');