scopeChain.js

/**
   Scope Chain - Scope chain is the process in which the JS look for the variable.
   It will first look into its local scope --> then Outer Scope --> then Global Scope
 */

function b() {
    var myVar = 3;
    console.log("I am inside B function");
}

function a() {
    b();
    var myVar = 2;
}

var myVar = 1;
console.log(myVar);

// Creating Closures 

function a() {
    function b() {
        var myVar = 3;
        console.log("I am inside B function");
    }
    b();    
    console.log(myVar);
    
}
var myVar = 1;
console.log(myVar);

// Given example on StackOverflow
var currentScope = 0; // global scope
function a () {
   var currentScope = 1, one = 'scope1';
   alert(currentScope);

  function b () {
      var currentScope = 2, two = 'scope2';
      alert(currentScope);

      function c () {
         var currentScope = 3, three = 'scope3';
         alert(currentScope);
         alert(one + two + three); // climb up the scope chain to get one and two
     }
     c();
  }
  b();
}
a();