Using the GNOME and KDE Desktops
George Ajam Computer Science Dept. College of Science
March, 8th 2012
Linux Desktop
General overview Below we will see an overview about the different software involved in the Linux desktop. The way they are ordered from the user on the top to the hardware on the bottom, should roughly reflect usage dependency between the software. Software on the top uses services of the software located below them. The next sections will give a short introduction to each of them.
The X Server
The X Window System1 (commonly X or X11) is a computer software system and network protocol that provides a graphical user interface (GUI) for networked computers. It creates a hardware abstraction layer where software is written to use a generalized set of commands, allowing for device independence and reuse of programs on any computer that implements X.
Special commands
xwininfo:Shows informations about windows related to the X Server xkill:Provides a graphical way to close the window resource of any window startx:Starts an Xserver and executes all commands in the file /home/
Display Manager
In the X Window System, an X display manager runs as a program that allows the starting of a session on an X server from the same or another computer. A display manager presents the user with a login screen which prompts for a username and password. A session starts when the user successfully enters a valid combination of username and password. Typical display managers are gdm for the Gnome desktop environment, kdm for the Kde desktop environment and xdm which is part of
the X software system. On Ubuntu, both gdm and kdm are services that can be started and stopped with the following commands: / etc / init . d / gdm start / stop / etc / init . d / kdm start / stop
Window Manager
window manager is system software that controls the placement and appearance of windows within a windowing system in a graphical user interface. Most window managers are designed to help provide a desktop environment. They work in conjunction with the underlying graphical system which provides required functionality such as support for graphics hardware, pointing devices, and a keyboard, and are often written and created using a widget toolkit.
The elements usually associated with window managers are those which allow the user to open, close, minimize, maximize, move, resize, and keep track of running windows, including window decorators.
Desktop Environment
In graphical computing, a desktop environment (DE) commonly refers to a style of graphical user interface (GUI) derived from the desktop metaphor that we see on most modern personal computers. These GUIs help the user in easily accessing, configuring, and modifying many important and frequently accessed specific operating system (OS) features.
A desktop environment typically consists of icons, windows, toolbars, folders, wallpapers, short- cuts and desktop widgets. Prominent desktop environments are Kde and Gnome. On an Ubuntu system, these can be installed by the following commands. sudo aptitude install kubuntu – desktop sudo aptitude install ubuntu – desktop