Module2: Demo: Using This Keyword

2_improving_readability_with_arrow_functions.md

@@ -61,3 +61,28 @@ let greeting = name => 'Hello ' + name;
 let message = greetings('John');
 console.log(message);
 ```
+
+## Bahavior of `this` Keyword
+
+`this` of regular function:
+* refers to the owner of the function we are executing
+  * for standalone function, `this` refers global window obj
+  * for function within object, `this` refers the object
+
+`this` of arrow function
+* Unlike regular functions, arrow functions do not have their own `this` value
+
+### Demo
+
+```javascript
+let message = {
+    name: 'John',
+    regularFunction: function() {
+        console.log(this);
+    },
+    arrowFunction: () => console.log(this)
+}
+
+message.regularFunction(); // {name: "John", regularFunction: f, arrowFunction: f}
+message.arrowFunction(); // {window: Window, self: Window, document: document, name: "", ...}
+```