<?
$user = "fireangel";
$pass = "1234";
if ($_post("user") == $user && $_post("pass") == $pass) {
header("http://www.example.com");
exit;
}
else { echo "username or password are wrong."; }
?>
<form method="post" action="blat.php">
username: <input type="text" name="user"><br>
password: <input type="password" name="pass"><br>
<input type="submit">
</form>