The Graphical User Interface on Linux

The graphical user interface (GUI) provides graphical images on the screen that can be selected using the mouse. The most familiar computer GUI is a windowing system. Many windows can coexist on the screen, with independent tasks being performed in each window. The user can open, close, move, resize, and otherwise manipulate the windows.

The desktop environment so familiar to Windows users is a windowing system that's intended to represent the top of your office desk. When your computer starts, you have an empty working surface. The tools you need to perform tasks are available on the desktop, such as icons and menus, tool trays, a clock, a calculator, and other tools. You can open whichever application you need on the working surface. In fact, you can open as many applications as you need, simultaneously, in different windows.

Linux offers two popular desktop environments:

• GNOME: GNU Network Object Model Environment (GNOME) is open source software, a project that's part of the GNU project. The first public version, GNOME 1.0, was released in March 1999.

• KDE: K Desktop Environment (KDE) is free, open source software produced by the KDE project. The first public version, KDE 1.0, was released in July 1998.

Because both emulate a desktop, they are similar in many ways. Both desktops provide the following:

• A work surface with icons on it.

• A bottom panel with icons that start applications or menus.

• Many applications, such as email software, browsers, file editors, etc.

• A menu for starting applications, almost identical to the Windows Start menu.

• Virtual desktops. That is, alternative desktops. You can have one virtual desktop set up with the tools for one project, such as icons, menus, and open software, and another virtual desktop set up with the tools for a different project. Then, you can switch between desktops, depending on which project you're working on. You can have several virtual desktops.

• Configuration tools that enable you to change and control much of the look and feel of the desktop

• Administrative tools for managing your system.

The differences between GNOME and KDE are mainly in the administrative utilities, the tools for configuring the desktop, and the default applications chosen for installation with the desktop. For example, both KDE and GNOME provide a Paint program, but it is not the same Paint program. Another example is that KDE ships with a word processor called KWord, whereas GNOME ships with AbiWord, but both provide access to OpenOffice.

Almost all Linux distributions provide GNOME or KDE. Some distributions allow you to choose which desktop to install while installing Linux. Many install both, allowing you to choose your desktop when you log in. Which you use is mainly a matter of personal preference. You may want to try both before you decide.

Some software packages only run under one desktop, GNOME or KDE. However, some packages designed for one desktop also run under the other desktop. And some packages are shipped with both desktops, such as the GIMP. When GNOME and KDE are both installed, all packages shipped with both are installed, forming a single pool of software packages. The desktop provides access to any package that can run with it. For instance, if a GNOME package can also run under KDE, the KDE start menu will show the package, even though the package actually shipped with GNOME.

Other GUIs

Many other GUIs in addition to KDE and GNOME are available. Linux epitomizes flexibility and configurability and gives choices whenever possible. Almost all Linux distributions include GNOME and KDE, but many include other GUIs as well. For instance, Mandrake includes a desktop called IceWM that is smaller and faster than GNOME or KDE.

Most users install desktops other than the big two for special purposes only, such as when installing Linux on a machine with limited resourcesa situation calling for a GUI that uses less disk space and/or memory. Of course, some people choose to use a different GUI just because they like it. Your Linux GUI can be quite elaborate and individualistic if you want to spend the time customizing it. In the future, when you are a Linux guru, you may want to look into other GUIs.