If you want to have your domain redirect to another page or folder on your domain you can create an index.php page and enter the following code...
<?php
header ('HTTP/1.1 301 Moved Permanently');
header ('Location: /shop/');
?>
In this example if you put the index.php file in your root folder of www.domainname.com any visitors would be redirected to www.domainname.com/shop/
