If you need a session type thing like what forums and various other sites use where you login and you password/name is kept until you log out so your password is not asked for on each page (inhale) visit
http://ca3.php.net/session for more info
if you dont need 'heavy duty'
<?
$pass = $_GET['pass'];
if($pass=="password"){
echo("This is the accessed part of your page with the right password :rolleyes: ");
}else{
echo("You have entered the wrong password :mad: ");
}
?>
<form method="get">
<input name="pass">
<input type="submit">
</form>