diff --git a/src/main/java/de/hitec/nhplus/Main.java b/src/main/java/de/hitec/nhplus/Main.java
index 2393731..fb533ea 100644
--- a/src/main/java/de/hitec/nhplus/Main.java
+++ b/src/main/java/de/hitec/nhplus/Main.java
@@ -37,10 +37,17 @@ public class Main extends Application {
     @Override
     public void start(Stage primaryStage) {
         this.primaryStage = primaryStage;
-        executePassword();
+        User user = executeLogin();
+        if(user != null){
+            executeMainApplication(user);
+        }
     }
 
-    private void executePassword() {
+    /**
+     * Executes the login.
+     * @return User The {@link User} object for the logged-in {@link User}. Is {@code null}, if the login was not successful,
+     */
+    private User executeLogin() {
         try {
 
             FXMLLoader loader = new FXMLLoader(Main.class.getResource("/de/hitec/nhplus/login/LoginView.fxml"));
@@ -55,12 +62,10 @@ public class Main extends Application {
             controller.initialize(loginStage);
 
             loginStage.showAndWait();
-
-            if(controller.user != null){
-                executeMainApplication(controller.user);
-            }
+            return controller.user;
         } catch (IOException exception) {
             exception.printStackTrace();
+            return null;
         }
     }
 
diff --git a/src/main/java/de/hitec/nhplus/fixtures/UserFixture.java b/src/main/java/de/hitec/nhplus/fixtures/UserFixture.java
index 7b3550f..bb75d7d 100644
--- a/src/main/java/de/hitec/nhplus/fixtures/UserFixture.java
+++ b/src/main/java/de/hitec/nhplus/fixtures/UserFixture.java
@@ -13,7 +13,12 @@ import java.sql.Connection;
 import java.sql.SQLException;
 import java.util.*;
 
-public class UserFixture implements Fixture<User>{
+/**
+ * {@link Fixture} for {@link User}.
+ *
+ * @author Dominik Säume
+ */
+public class UserFixture implements Fixture<User> {
     private static final String SCHEMA = "/de/hitec/nhplus/login/database/User.sql";
     private static final String PERMISSION_SCHEMA = "/de/hitec/nhplus/login/database/UserPermission.sql";
     private static final String TO_NURSE_SCHEMA = "/de/hitec/nhplus/login/database/UserToNurse.sql";
@@ -94,7 +99,7 @@ public class UserFixture implements Fixture<User>{
 
         UserDao dao = DaoFactory.getInstance().createUserDAO();
         Map<String, User> usersByUsername = new HashMap<>();
-        for (User user : users){
+        for (User user : users) {
             dao.create(user);
             usersByUsername.put(user.getUsername(), user);
         }
diff --git a/src/main/java/de/hitec/nhplus/login/Permissions.java b/src/main/java/de/hitec/nhplus/login/Permissions.java
index 8420986..2f53369 100644
--- a/src/main/java/de/hitec/nhplus/login/Permissions.java
+++ b/src/main/java/de/hitec/nhplus/login/Permissions.java
@@ -1,5 +1,11 @@
 package de.hitec.nhplus.login;
 
+/**
+ * A simple class holding the bitmasks for all permissions.
+ * This is a class instead of an enum, for ease of use.
+ *
+ * @author Dominiok Säume
+ */
 public class Permissions {
     public final static int EVERYBODY = 0b0;
     public final static int NURSE = 0b1;
diff --git a/src/main/java/de/hitec/nhplus/login/User.java b/src/main/java/de/hitec/nhplus/login/User.java
index 50e604f..b58e6f2 100644
--- a/src/main/java/de/hitec/nhplus/login/User.java
+++ b/src/main/java/de/hitec/nhplus/login/User.java
@@ -7,8 +7,13 @@ import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 import java.security.SecureRandom;
 
-public class User {
 
+/**
+ * The model for a {@link User}.
+ *
+ * @author Dominik Säume
+ */
+public class User {
 
     private int id;
     private String username;
@@ -17,6 +22,10 @@ public class User {
     private int permissions = 0;
     private Nurse nurse;
 
+
+    /**
+     * This constructor allows instantiating a {@link User} object with all existing fields.
+     */
     public User(
             int id,
             String username,
@@ -33,6 +42,9 @@ public class User {
         this.nurse = nurse;
     }
 
+    /**
+     * This constructor allows instantiating a {@link User} object.
+     */
     public User(
             String username,
             int permissions,
@@ -42,6 +54,12 @@ public class User {
         this.permissions = permissions;
         this.nurse = nurse;
     }
+
+    /**
+     * Sets the {@link User} password. The {@link User} will need to be manually stored with the
+     * {@link de.hitec.nhplus.login.database.UserDao UserDao}, for changes to persists.
+     * @param password The new Password
+     */
     public void setPassword(String password) {
         try {
             SecureRandom random = new SecureRandom();
@@ -59,6 +77,7 @@ public class User {
     public boolean hasNursePermissions(){
         return (permissions & Permissions.NURSE) != 0;
     }
+
     public boolean hasAdminPermissions(){
         return (permissions & Permissions.MANAGEMENT) != 0;
     }
diff --git a/src/main/java/de/hitec/nhplus/nurse/Nurse.java b/src/main/java/de/hitec/nhplus/nurse/Nurse.java
index 22c4b49..7fa94b9 100644
--- a/src/main/java/de/hitec/nhplus/nurse/Nurse.java
+++ b/src/main/java/de/hitec/nhplus/nurse/Nurse.java
@@ -44,7 +44,7 @@ public class Nurse extends Person {
 
     /**
      * This constructor allows instantiating a {@link Nurse} object with
-     * specifying if the nurse is locked or not.
+     * specifying whether the {@link Nurse} is locked or not.
      */
     public Nurse(
             String firstName,
diff --git a/src/main/java/de/hitec/nhplus/utils/tab/TabStruct.java b/src/main/java/de/hitec/nhplus/utils/tab/TabStruct.java
index 9a49919..ad1325d 100644
--- a/src/main/java/de/hitec/nhplus/utils/tab/TabStruct.java
+++ b/src/main/java/de/hitec/nhplus/utils/tab/TabStruct.java
@@ -1,5 +1,11 @@
 package de.hitec.nhplus.utils.tab;
 
+/**
+ * A simple class holding the data needed for constructing a tab.
+ *
+ * @author Dominiok Säume
+ * @see TabManager
+ */
 public class TabStruct {
     public String title;
     public String view;