undecalred and undefined
Javascript undefined and not udefined
JavaScript
'use strict'
var a;
//a = 20;
console.log(typeof a)
console.log(a)
b = 20;
console.log(typeof b);
console.log(b)
'use strict'
var a;
//a = 20;
console.log(typeof a)
console.log(a)
b = 20;
console.log(typeof b);
console.log(b)