Joomla's ACL really has two pieces to it.
One part is who can create, edit, delete, and publish what, and the other side of
it is who can see what.
So that side of it, the who can see what side, is controlled by something
called access levels, and I just want to acquaint you with these access levels real quickly.
So here under Users, if we go to Access Levels,
by default, there are four access levels for our Web site.
So Public, Registered, and Special have been around forever inside of Joomla,
and Guest is new to this version of Joomla.
So Public indicates that that is the public.
Anybody who comes to visit the front-end to your Web site, this is
information that anybody can see, and they don't have to be logged in to the Web site to see it.
Registered means that you can log in to the front-end of the Web site; that's the
registered user group side of this.
The Registered access level controls who can see what on the front-end of the
Web site once they are logged in.
So that would actually include
the Registered user group, as well as Authors, Editors, Publishers, Managers,
Administrators, and Super administrators; all of them have the ability to log in to
the front-end of the Web site.
All of them can see the content that's here set up for with the
Registered access level.
Special means that user groups of Author and higher can see that particular
content; so Authors, Editors, Publishers, Managers, Administrators, and Super
administrators, or Super Users, can all see that particular information on the Web site.
Special is used a lot here in the back-end for controlling who can see the modules.
So like the menu module here at the top of the screen in my administrator side,
the access level associated with that is Special.
And I recommend that you don't really use Special for the front-end of the
Web site. It's become an incredibly useful thing on the back-end of Joomla in particular.
And then the last level, which is new this time around, is the Guest level, and
the Guest level indicates that you are new to the Web site, and you are looking
at something, but this particular item should display only if you are not logged
in, and if you are logged in,
then this particular item would not display at all.
So you might have, as we will have later on in this video, you might have a link
that says become a distributor.
And that's available if you're not logged in to the Web site.
But if you log in to the Web site, that link goes away.
If you log in, obviously you're a distributor,
so that link that says become a distributor, it's gone, and it's replaced with,
perhaps, some other information, and that's what we will be building later on in
this particular chapter.
So remember that access levels have to do with who can see what; that's all. Who
can see what, either of the front-end or the back-end to the Web site.
And everything else; creating, editing, deleting, publishing, content, logging in,
a whole bunch of other things, that is all under control of the permissioning
system inside of Joomla
in the core permissions.