diff --git a/src/main/java/ch/zhaw/gartenverwaltung/Settings.java b/src/main/java/ch/zhaw/gartenverwaltung/Settings.java
index 8433dce..491db5d 100644
--- a/src/main/java/ch/zhaw/gartenverwaltung/Settings.java
+++ b/src/main/java/ch/zhaw/gartenverwaltung/Settings.java
@@ -6,21 +6,58 @@ import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.SimpleBooleanProperty;
 
 import java.util.List;
+import java.util.Objects;
 
+/**
+ * Singleton Class to store default Settings and User Settings
+ */
 public class Settings {
-    private static final Settings instance;
-    private HardinessZone currentHardinessZone = HardinessZone.ZONE_8A;
-    private final BooleanProperty showTutorial = new SimpleBooleanProperty(false);
-    private SmtpCredentials smtpCredentials = new SmtpCredentials("imap.gmail.com", "587", "pm3.hs22.it21b.win.team1@gmail.com", "pm3.hs22.it21b.win.team1@gmail.com", "bisefhhjtrrhtoqr", true);
-    // Gmail Address: pm3.hs22.it21b.win.team1@gmail.com
-    // Gmail Passwort: Gartenverwaltung.PM3.2022
-    // E-Mail Inbox: https://www.mailinator.com/v4/public/inboxes.jsp?to=pm3.hs22.it21b.win.team1
-    private String mailNotificationReceivers = "pm3.hs22.it21b.win.team1@mailinator.com";
-    private String mailNotificationSubjectTemplate = "Task %s is due!"; // {0} = Task Name
-    private String mailNotificationTextTemplate = "Dear user\nYour gardentask %s for plant %s is due at %tF. Don't forget to confirm in your application if the task is done.\nTask description:\n%s"; // {0} = Task Name, {1} = plantname, {2} = nextExecution, {3} = Task description
+    /*
+     * The Class instance to use everywhere
+     */
 
+    private static final Settings instance;
+    /**
+     * The current Hardiness zone initialized as default value Zone_8A
+     */
+    private HardinessZone currentHardinessZone = HardinessZone.ZONE_8A;
+    /**
+     * Setting to show or hide the Tutorial in Main Menu
+     */
+    private final BooleanProperty showTutorial = new SimpleBooleanProperty(false);
+    /**
+     * The SMTP Credentials which are used to send E-Mail Notifications
+     * The following Google Account is created for Testing:
+     * E-Mail Address: pm3.hs22.it21b.win.team1@gmail.com
+     * Account Password: Gartenverwaltung.PM3.2022
+     * SMTP Password: bisefhhjtrrhtoqr
+     */
+    private SmtpCredentials smtpCredentials = new SmtpCredentials("imap.gmail.com", "587", "pm3.hs22.it21b.win.team1@gmail.com", "pm3.hs22.it21b.win.team1@gmail.com", "bisefhhjtrrhtoqr", true);
+    /**
+     * List of Receivers for E-Mailnotifications. Multiple E-Mailadresses can be separated by ";"
+     * Following Public E-mail address  was used for Testing: pm3.hs22.it21b.win.team1@mailinator.com
+     * The E-Mail inbox of this address can be found here: https://www.mailinator.com/v4/public/inboxes.jsp?to=pm3.hs22.it21b.win.team1
+     */
+    private String mailNotificationReceivers = "pm3.hs22.it21b.win.team1@mailinator.com";
+    /**
+     * String Template to create E-Mail Subject for Notifications
+     * Variables: Task Name
+     */
+    private String mailNotificationSubjectTemplate = "Task %s is due!";
+    /**
+     * String Template to create E-Mail Text for Notifications
+     * Variables: Task Name, plant Name, nextExecution, Task description
+     */
+    private String mailNotificationTextTemplate = "Dear user\nYour gardentask %s for plant %s is due at %tF. Don't forget to confirm in your application if the task is done.\nTask description:\n%s";
+
+    /**
+     * Location of the garden can be set by user (Used for Weather Service)
+     */
     private String location = "";
 
+    /*
+      Create Instance of Settings
+     */
     static {
         instance = new Settings();
     }
@@ -29,14 +66,21 @@ public class Settings {
         return Settings.instance;
     }
 
+    /**
+     * Private constructor to prevent Classes from creating more instances
+     */
     private Settings() {}
 
     public HardinessZone getCurrentHardinessZone() {
         return currentHardinessZone;
     }
 
+    /**
+     * Method to set the current Hardiness Zone. If no Hardiness Zone is given the default zone (ZONE_8A) will be used.
+     * @param currentHardinessZone the new Hardiness Zone
+     */
     public void setCurrentHardinessZone(HardinessZone currentHardinessZone) {
-        this.currentHardinessZone = currentHardinessZone;
+        this.currentHardinessZone = Objects.requireNonNullElse(currentHardinessZone, HardinessZone.ZONE_8A);
     }
 
     public void setShowTutorial (boolean showTutorial) {