Breadcrumbs:

Back up to the home page to navigate between projects or to the Project Console (if you click the name of your project).

Up arrow:

Takes you up one folder level in the Repository or back from a preview to a list view.

Navigation panel:

Takes you to other parts of your Project or back to your Project Console.

WebDAV:

Gives you the Windows Explorer/WebDAV location of your file or folder (copy/paste into Windows Explorer).