Truthy and Falsy values and equality operators

script.js

@@ -153,7 +153,7 @@ if (age < 13) {
 /*****************************
 * The Ternary Operator and Switch Statements
 */
-
+/*
 var firstName = 'John';
 var age = 14;
 // Ternary operator
@@ -197,4 +197,21 @@ switch (true) {
 }
 
 
+/*****************************
+* Truthy and Falsy values and equality operators
+*/
+
+// falsy values: undefined, null, 0, '', NaN
+// truthy values: NOT falsy values
+var height;
+height = 23;
+if (height || height === 0) {
+    console.log('Variable is defined');
+} else {
+    console.log('Variable has NOT been defined');
+}
+// Equality operators
+if (height === '23') {
+    console.log('The == operator does type coercion!');
+}