I know asp better, but php... I found some solutions on the php redirect, but i do not know which one is the better. Can you give me some advices?
http://www.webmaster-talk.com as an example

-------------Header---------------
<?php
$url = http://www.webmaster-talk.com;
if (isset($url))
{
Header("Location: $url");
}
?>
------------java script-------------------
<? php
$url=http://www.webmaster-talk.com;
echo "<SCRIPT LANGUAGE=\"java script\">location.href='$url'</SCRIPT>";
?>

Neither is better or worse; they're just different.

If you call header('Location:...') in PHP the server will issue a 302 redirect to the user. You should use this if you need to redirect a user without displaying any content first.

Using javascript, the user won't be redirected until after the content of the site is downloaded. This allows you to display a message to the user (use setTimeout to delay the redirect). Obviously the user must have javascript enabled for this to work.