diff --git a/content/login.php b/content/login.php
index af502c0..6e2c70b 100644
--- a/content/login.php
+++ b/content/login.php
@@ -19,7 +19,7 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
     $user = $dao->findUser($email);
 
     // Prüfung der Zugangsdaten
-    if ($user && $user["password"] === $password) {
+    if ($user && password_verify($password, $user["password"])){
 
         // Session setzen = User ist eingeloggt
         $_SESSION["user"] = $user["username"];
diff --git a/content/register.php b/content/register.php
index 3f954eb..6f8c88a 100644
--- a/content/register.php
+++ b/content/register.php
@@ -15,7 +15,10 @@ if ($_SERVER["REQUEST_METHOD"] === "POST") {
     $email = $_POST["email"];
     $vorname = $_POST["vorname"];
     $nachname = $_POST["nachname"];
-    $password = $_POST["password"];
+    $password = password_hash(
+            $_POST["password"],
+            PASSWORD_DEFAULT
+    );
 
     // Prüfen, ob die E-Mail bereits registriert ist
     if ($dao->findUser($email)) {
diff --git a/includes/UserDAO.php b/includes/UserDAO.php
index a0d60ce..6ceb6c4 100644
--- a/includes/UserDAO.php
+++ b/includes/UserDAO.php
@@ -1,6 +1,7 @@
 <?php
+require_once "UserDAOInterface.php";
 
-class UserDAO {
+class UserDAO implements UserDAOInterface {
 
     private string $file = "data/users.json";
 
diff --git a/includes/UserDAOInterface.php b/includes/UserDAOInterface.php
new file mode 100644
index 0000000..15468da
--- /dev/null
+++ b/includes/UserDAOInterface.php
@@ -0,0 +1,7 @@
+<?php
+
+interface UserDAOInterface {
+    public function findUser($email);
+    public function addUser($email, $username, $password);
+    public function deleteUser($email);
+}
\ No newline at end of file