Structure Plugin lets you have several independent structures in JIRA. Manage Structures page lets you view, search for, create, and delete structures as well as change their settings.

To open Manage Structures page, go to Structure menu in the top navigation bar, and then select Manage Structures.

   

 

Manage Structure page contains the following tabs:

Since anonymous users can't create structures and can't mark structures as their favorites, Favorite and My tabs are not shown when you are not logged in.

More about managing structures: