JavaScript Hoisting

javascript-hoisting.js

console.log(y === undefined); // "true"
var y = 3;
 
// will return a value of undefined
var myvar = "my value";
(function() {
  console.log(myvar); // undefined
  var myvar = "local value";
})();

// this is equivalent
var myvar = "my value";
(function() {
  var myvar;
  console.log(myvar); // undefined
  myvar = "local value";
})();