Administrator is the highest permission level that any user can have on a workspace.   Administrators have full access to all content and can modify the settings of a workspace at any time.  Do not grant any user Administrator access over your workspace unless absolutely necessary.  The changes to the settings that Administrators make cannot be limited by any other Administrator, and they have complete control over everything in the workspace.

Here are some of the most common operations that an Administrator will perform on a workspace, that other users cannot.  Of course, Administrators can also perform all of the actions that Readers, Writers, and Editors can perform on a workspace.