diff --git a/login.php b/login.php
index 0bc4d0e..aa62402 100644
--- a/login.php
+++ b/login.php
@@ -3,22 +3,22 @@ session_start();
 $pdo = new PDO('mysql:host=localhost;dbname=usertable', 'usertable', 'password');
  
 if(isset($_GET['login'])) {
-    $email = $_POST['email'];
+    $username = $_POST['username'];
     $password = $_POST['password'];
     
-    $statement = $pdo->prepare("SELECT * FROM users WHERE email = :email");
-    $result = $statement->execute(array('email' => $email));
+    $statement = $pdo->prepare("SELECT * FROM users WHERE username = :username");
+    $result = $statement->execute(array('username' => $username));
     $user = $statement->fetch();
         
-    //Überprüfung des Passworts
     if ($user !== false && password_verify($password, $user['password'])) {
         $_SESSION['userid'] = $user['id'];
         $_SESSION['email'] = $user['email'];
+        $_SESSION['username'] = $user['username'];
         $_SESSION['givenName'] = $user['givenName'];
         $_SESSION['lastName'] = $user['lastName'];
         die('successfull. go to: <a href="secure.php">secure page</a>');
     } else {
-        $errorMessage = "somethings wrong (maybe wrong password or wrong email)<br>";
+        $errorMessage = "somethings wrong (maybe wrong password or wrong user)<br>";
     }
     
 }
@@ -37,8 +37,8 @@ if(isset($errorMessage)) {
 ?>
  
 <form action="?login=1" method="post">
-E-Mail:<br>
-<input type="email" size="40" maxlength="250" name="email"><br><br>
+Your Username:<br>
+<input type="text" size="40" maxlength="250" name="username"><br><br>
  
 Your password:<br>
 <input type="password" size="40" name="password"><br>
diff --git a/register.php b/register.php
index 8530fd0..5261d9d 100644
--- a/register.php
+++ b/register.php
@@ -15,6 +15,7 @@ $showFormular = true;
 if(isset($_GET['register'])) {
     $error = false;
     $email = $_POST['email'];
+    $username = $_POST['username'];
     $givenName = $_POST['givenName'];
     $lastName = $_POST['lastName'];
     $password = $_POST['password'];
@@ -45,11 +46,22 @@ if(isset($_GET['register'])) {
         }    
     }
 
+    if(!$error) { 
+        $statement = $pdo->prepare("SELECT * FROM users WHERE username = :username");
+        $result = $statement->execute(array('username' => $username));
+        $user = $statement->fetch();
+        
+        if($user !== false) {
+            echo 'already a user here<br>';
+            $error = true;
+        }    
+    }
+    
     if(!$error) {    
         $password_hash = password_hash($password, PASSWORD_DEFAULT);
         
-        $statement = $pdo->prepare("INSERT INTO users (email, givenName, lastName, password) VALUES (:email, :givenName, :lastName, :password)");
-        $result = $statement->execute(array('email' => $email, 'givenName' => $givenName, 'lastName' => $lastName, 'password' => $password_hash));
+        $statement = $pdo->prepare("INSERT INTO users (email, username, givenName, lastName, password) VALUES (:email, :username, :givenName, :lastName, :password)");
+        $result = $statement->execute(array('email' => $email, 'username' => $username, 'givenName' => $givenName, 'lastName' => $lastName, 'password' => $password_hash));
         
         if($result) {        
             echo 'successfull registered. <a href="login.php">Login</a>';
@@ -66,12 +78,14 @@ if($showFormular) {
 <form action="?register=1" method="post">
 E-Mail:<br>
 <input type="email" size="40" maxlength="250" name="email"><br><br>
+Username:<br>
+<input type="text" size="40" name="username"><br><br>
 Given Name:<br>
 <input type="text" size="40" name="givenName"><br><br>
 Family Name:<br>
 <input type="text" size="40" name="lastName"><br><br>
 Password:<br>
-<input type="password" size="40"  name="password"><br>
+<input type="password" size="40"  name="password"><br><br>
  
 Password (aganin):<br>
 <input type="password" size="40" name="password_confirm"><br><br>
diff --git a/secure.php b/secure.php
index 769ee86..c2d8d88 100644
--- a/secure.php
+++ b/secure.php
@@ -6,11 +6,12 @@ if(!isset($_SESSION['userid'])) {
 }
  
 $userid = $_SESSION['userid'];
+$username = $_SESSION['username'];
 $useremail = $_SESSION['email'];
 $usergn = $_SESSION['givenName'];
 $userln = $_SESSION['lastName'];
  
-echo "Hi ".$usergn;
+echo "Hi ".$username;
 echo "<br/>";
 echo "Your User-ID is: ".$userid;
 echo "<br/>";