Menu Bar Guides

It won't take long to realize that Mac OS X has only one Menu Bar and that it is always positioned at the top of the screen.  This is in stark contrast to Windows environments where each application window has its own dedicated menu bar.
Menulets are of small icons located at the upper right corner of the Menu Bar.  Many Windows users are accustomed to the Windows taskbar that is located on the lower right corner of a Windows screen.  Menulets are similar to the taskbar icons in Windows.
When you're logged into the Mac OS X Desktop, you'll see an Apple icon located at the upper left corner of the screen.  When you click on it a menu opens below and this menu is called the Apple Menu.  It's perhaps the most important Menu in Mac OS X.  Depending on the version of Mac OS X you're using, the icon may have a different color.  For example, in Leopard it's Black where as in Tiger it's blue.