The first element is the Navigation bar across the top of the browser window. The purpose of this element is to ensure that you are able to get back to where you started from. All that you need to do is to click on the button that is highlighted as the mouse pointer moves over it.
The second element is the contents window. The purpose of the contents window is the same as that of a table of contents in a book. The facilities that are available on the site are listed in this window. All that needs to be done to go to a particular section, is to click on the underlined word that you want to go to.
The third element is the main window. The purpose of the main window is to provide a consistent place for the results of your actions or choices to be displayed.