The Management Window is where you control the navigation and content of your site.
The Action Window alters depending on what icon you have selected in your Management Window. It is also the window which you make all changes to your pages / images / navigation etc.
The Action Desktop takes you back to basics, you will find a "Return to Action Desktop" at the bottom of every Primary Node Control screen.
Search for something - if you are looking for an image or a particular page that mentions a phrase you can select this and define the options.
Another way to find a page or folder that you could be missing.
A manager (or yourself) may have made notes either via the administration or via the website for action at a later date. If you select this button it will open all pages that currently have notes attached to them.
Will open your entire tree allowing you to see all nodes at once.
NB/ if you have a large tree this could take a long time.