Site Administrator control panel is designed to control (administration) site.
It's a secret door to the site, the backdoor.
Sections of the site administrator closed to public access, viewing, indexing by search engines. Log in admin / section of the site – by entering the username/password.
There are different levels of access (administration) site and the different roles of users (administrators moderators).
The developer has full access to the site, and identifies the role of users, access levels (and functions attached to them).
He can assign new users or change the level of administrative access to an existing user.