Once an X server is running, X client applications can connect to it and create a GUI for the user. A range of GUIs are possible with Red Hat Enterprise Linux, from the rudimentary Tab Window Manager to the highly developed and interactive GNOME desktop environment that most Red Hat Enterprise Linux users are familiar with.
To create the latter, more comprehensive GUI, two main classes of X client application must connect to the X server: a desktop environment and a window manager.
35.2.1. Desktop Environments
A desktop environment integrates various X clients to create a common graphical user environment and development platform.
Desktop environments have advanced features allowing X clients and other running processes to communicate with one another, while also allowing all applications written to work in that environment to perform advanced tasks, such as drag and drop operations.
Red Hat Enterprise Linux provides two desktop environments:
Both GNOME and KDE have advanced productivity applications, such as word processors, spreadsheets, and Web browsers; both also provide tools to customize the look and feel of the GUI. Additionally, if both the GTK+ 2 and the Qt libraries are present, KDE applications can run in GNOME and vice-versa.