anchor.diff:  function addNum(x) {
       // addNum return anonymous function
       return function (y) {
  -        // Note how x value accessible to this scope 
  +        // Note how x value accessible to this scope
           return x + y;
       };
   var addTwo = addNum(2);
  
positive.code: 
  The following example demonstrate the concept of local and global scope
  
  ```javascript
  var globalVar = "I'm global var";
  
  function myFunc() {
  
      // This will create globalVar in local context of myFunc
      // which doesn't interfear with the global one
      var globalVar = "I'm local var";
      return globalVar;
  
  
negative.code: 
  console.log('myFunc scope globalVar:', myFunc());
  console.log('Global scope globalVar:', globalVar);
  ....
  
  Output:
  
  