Grant Administrative Access in SharePoint 2010
You’ll find a number of different administrator levels in a SharePoint 2010 deployment. Administrators usually have full access over the domain they’ve been charged with administering. The levels of administrators in SharePoint are
Server administrators: By virtue of having local administrator access to the physical server, a server administrator can do anything from the server console. Server administrators are usually members of the technical staff.
Site collection administrators: These administrators can access everything within a site collection. SharePoint allows you to appoint a primary and secondary administrator for each site collection.
Site administrators: Members of the Site Owners SharePoint group are the site administrators. If subsites inherit permissions, a site administrator has full access to each site.
To set the site collection administrators for a site:
Click the Site Permissions header in the People and Groups page (choose Site Actions→Site Permissions).
The Permissions page appears.
Choose Settings→Site Collection Administrators.
The Site Collection Administrators page appears.
Enter the user accounts for the people who are site collection administrators and then click OK.
Assigning accounts to be site collection administrators is one time when it’s acceptable to use individual user accounts instead of domain groups.