$result = mysql_query('SELECT * FROM account WHERE username="'.$username.'" and password="'.$password.'"');
		   if (!$result)
		   {
			die ("Accoun't invalid: " . mysql_error());
			}
			   $_SESSION['username'] = $username;
			   header('Location: home.php');
			   session_start();
			   echo 'Welcome '.$SESSION['username'];}
		?>