<?php
echo "<h1> Register </h1>";

if( isset($_POST['submit']) && $_POST['submit']){
// Initialise $_POST variables eg:
$fullname = $_POST['fullname'];
$username = $_POST['username'];
$password = md5($_POST['password']);
$repeatpassword = md5($_POST['repeatpassword']);

//check for existence

if ($fullname&&$username&&$password&&$repeatpassword)
{

}
else
	echo "Please fill in all fields";

?>

<form action = "register.php" method="post">
	<table>
    	<tr>
        	<td>
            Your full name:
            </td>
            <td>
            <input type="text" name="fullname"/>
            </td>
       </tr>
       <tr>
        	<td>
            Choose a username:
            </td>
            <td>
            <input type="text" name="username"/>
            </td>
       </tr>
       <tr>
        	<td>
            Choose a password:
            </td>
            <td>
            <input type="password" name="password"/>
            </td>
            <tr>
        	<td>
           Repeat your password:
            </td>
            <td>
            <input type="password" name="repeatpassword"/>
            </td>
       </tr>
       </tr>
    </table>
    <p>
   <input type="submit" name="submit" value="Register"/></p>
   </form>