If you create a new menu item type Category blog or Featured articles, a set of Intro texts will be displayed with Read More links on that page. By clicking on the Read More link you will get to the full article view.
It can be useful to restrict access to the full article view for not registered visitors and leave just the intro texts readable to public. To restrict access to full article view, do the following:
'Show Unauthorised Links' = 'Yes' - allows users to see the intro text of Articles their user group are not allowed access to
'Show Intro Text' = 'Hide' - hides the intro text when the page is displayed.
'Show Intro Text' = 'Show' - displays the intro text and main text
N.B. Text in Articles without a readmore is treated as 'intro text'. If you have Articles that are registered only but do not have them displayed on a readmore then add a readmore to the article ... otherwise the whole article will be visible to all users.