GNOME Components

From a user’s point of view, the GNOME interface has four components: the desktop, the panels, the main menus, and the file manager. You can display two panels—one used for menus, application icons, and running applets at the top of the screen, and another at the bottom of the screen used primarily for managing your windows and desktop spaces. In its standard default configuration for Ubuntu, the GNOME desktop will display nothing. If you have any removable media, such as CD/DVD discs or attached partitions, icons for those will be displayed.

In addition to menus and items already mentioned, the top panel has icons for the Mozilla Firefox Web browser (globe with fox) and the Evolution mail tool (envelope). At the far right are the time and date icons. An update button will appear if updates are available. You can use the update button to update your system automatically. The bottom panel holds icons for minimized windows as well as running applets and the trash can. These include a Workspace Switcher (the colored squares) at the right. An icon on the left lets you minimize all your open windows. When you open a window, a corresponding button for it will be displayed in the lower panel, which you can use to minimize and restore the window size. Click the trash can icon on the far right side of the bottom panel to empty deleted files stored there.

Your home directory, as well as any partitions, removable media, and remote file systems, can be accessed from entries on the Places menu on the top panel. If you want an icon for an item displayed on your desktop, right-click the item in the Places menu and choose Add To Desktop. To add the computer icon to the desktop, you would open the Places menu, right-click Computer, and select Add This Launcher To The Desktop. You can do the same for Network, which will show just your remote directories and devices. The home directory icon cannot be added to the desktop.

To start a program, you can select its entry from the Applications menu. You can also click its application icon in the panel (if one appears) or drag-and-drop a data file to its icon. To add an icon for an application to the desktop, right-click its name in the Applications menu and choose Add This Launcher To The Desktop.

Source of Information : McGraw Hill Ubuntu The Complete Reference