Access to pages

Hi,
I would like to know how I can configure the visibility of the web site,
For example, the visibility of some pages is possible only for registered users etc..

Thanks
    Simone

Hi
Simply you can manage access page in Admin site
go to menu Configuration/Access Control List

Regards

ok, but how can I disable the visibility of the sections / pages for all users (registered and unregistered).
For Example I want to remove the Categories section.