title: It needs to connect to a database, but it doesn't.
body: <pre><code>&lt;?php 
  session_start();
  $host="localhost";
  $username="root";
  $password="";
  $db_name="registrering";
  $tbl_name="users";
  
  $conn = mysqli_connect($host, $username, $password, $db_name);
  
  if(!$conn) {
  die("Connection failed: " . mysqli_connect_error());
  }
  
   ?&gt;
  &lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;user registration system using php and PHP and Mysq&lt;/title&gt;
      &lt;!---&lt;link rel="stylesheet" type="text/css" href="style.css"&gt;--&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;div style="float:right; width:70%"&gt;
  &lt;table width="150px" border="0" cellpadding="3" cellspacing="1"&gt;
          &lt;h2&gt;Registrer&lt;h2/&gt;
          &lt;form method="post" action=" "&gt;
          &lt;br&gt;
              &lt;tr&gt;
                  &lt;td&gt;Brugernavn&lt;/td&gt;
                  &lt;td&gt;:&lt;/td&gt;
                  &lt;td&gt;&lt;input type="text" name="Brugernavn"&gt; &lt;/td&gt;
              &lt;/tr&gt;
              &lt;br&gt;
              &lt;tr&gt;
                  &lt;td&gt;Email&lt;/td&gt;
                  &lt;td&gt;:&lt;/td&gt;
                  &lt;td&gt;&lt;input type="text" name="Email"&gt; &lt;/td&gt;
              &lt;/tr&gt;
              &lt;br&gt;
              &lt;tr&gt;
                  &lt;td&gt;Password&lt;/td&gt;
                  &lt;td&gt;:&lt;/td&gt;
                  &lt;td&gt;&lt;input type="password" name="Password"&gt;&lt;/td&gt;
              &lt;/tr&gt;
                  &lt;input type="submit" name="registrer" value="Registrer"&gt;
  
                  &lt;p&gt;
                      Allerede medlem? &lt;a href="login.php"&gt;Log ind&lt;/a&gt;
                  &lt;/p&gt;
          &lt;/form&gt;
  &lt;/div&gt;
  &lt;/table&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  &lt;?php
  if (isset($_POST["registrer"]))
  {
  $my_username=$_POST["Brugernavn"];
  $my_email=$_POST["Email"];
  $my_password=$_POST["Password"];
  
  $sql = "INSERT INTO 'users'(`username`, `email`, `password`) VALUES ('$my_username','$my_email','$my_password')";
  $resultat = mysqli_query($conn, $sql);
  }
  ?&gt;
  </code></pre>
  
  <p>It needs to connect to a database, but it doesn't. It's on a localhost and we can't insert data into a database. The database consists of a username, email and password. 
  We are using varchar(65) and utf8_general_ci.</p>