[ragtek]

globaltemplates => cached global for the page (allways)

actiontemplates => cached if a special action is called ($_GET['do'] == 'whatever')

you could also make:

PHP Code:

$globaltemplates = array('foo', 'bar');

if ($_REQUEST['do'] == 'xy')
{
$globaltemplates[] = 'xyz';
$globaltemplates[] = 'newpost_preview';
} 


with actiontemplates:

PHP Code:

$globaltemplates = array('foo', 'bar');
$actiontemplates = array(
    'xy' => array(
        'xyz', 'newpost_preview',
    )
);