diff --git a/src/server.js b/src/server.js
index 099e3ac..4eb5c3d 100644
--- a/src/server.js
+++ b/src/server.js
@@ -24,7 +24,8 @@ var redirect_uri = process.env.CALLBACK; // Your redirect uri
 var environment = process.env.NODE_ENV || 'prod';
 
 /**
- * Generates a random string containing numbers and letters
+ * Generates a random string containing numbers and letters.
+ * From Spotify tutorial.
  * @param  {number} length The length of the string
  * @return {string} The generated string
  */
@@ -49,6 +50,9 @@ if (environment == 'prod' || environment == 'production') {
 app.use(express.static(__dirname + '/public'))
     .use(cookieParser());
 
+/**
+ * From Spotify tutorial.
+ */
 app.get('/login', function (req, res) {
 
     var state = generateRandomString(16);
@@ -66,6 +70,9 @@ app.get('/login', function (req, res) {
         }));
 });
 
+/**
+ * From Spotify tutorial.
+ */
 app.get('/callback', function (req, res) {
 
     // your application requests refresh and access tokens
@@ -117,6 +124,9 @@ app.get('/callback', function (req, res) {
     }
 });
 
+/**
+ * From Spotify tutorial.
+ */
 app.get('/refresh_token', function (req, res) {
 
     // requesting access token from refresh token