Separation of the GUI and the Kernel

Taking a cue from the Macintosh design concept, Windows developers integrated the graphical
user interface (GUI) with the core operating system. One simply does not exist without the
other. The benefit to this tight coupling of the operating system and the user interface is
consistency in the appearance of the system. Although Microsoft does not impose rules as
strict as Apple’s with respect to the appearance of applications, most developers tend to stick
with a basic look and feel among applications.

On the other hand, Linux (like UNIX in general) has kept the two elements—user interface
and operating system—separate. The X Window System interface is run as a user-level
application, which makes it more stable. If the GUI (which is very complex for both Windows
and Linux) fails, Linux’s core does not go down with it. The X Window System also differs
from the 2000 GUI in that it isn’t a complete user interface: It only defines how basic objects
should be drawn and manipulated on the screen.

NOTE
Unfortunately, the lack of tight integration of The X Window System into Linux has a
downside: While the operating system is very robust, X Windows is somewhat more
prone to problems with certain hardware or graphics settings. The Linux version of the
“three-finger salute” is CTRL-ALT-BACKSPACE, which kills X.

The most significant feature of the X Window System is its ability to transmit windows
across a network and display them on another workstation’s screen. This allows a user sitting
on Host A to log in to Host B, run an application on Host B, and have all of the output routed
back to Host A. It is possible for two people to be logged in to the same machine, running a Linux equivalent of Microsoft Word (such as OpenOffice, WordPerfect, or StarOffice) at the
same time. Even when using Terminal Services, Windows 2000 and Windows XP users are
limited to a single user at a time running a given application and using the display.
In addition to the X Windows core, a window manager is needed to create a useful
environment. Most Linux distributions (including Red Hat) come with several window
managers and include support for GNOME and KDE, both of which are available on other
variants of UNIX as well. When set as default, either GNOME or KDE offers an environment
that is friendly even to the casual Windows user.

So which is better—Windows 2000 or Linux—and why? That depends on what you are
trying to do. The integrated environment provided by Windows 2000 is convenient, and
because it is more standardized, it is less complex than Linux, but it lacks the X Windows
feature that allows applications to display their windows across the network on other
workstations. Windows 2000’s GUI is consistent but cannot be turned off, whereas X
Windows doesn’t have to be running (and consuming valuable memory) on a server.