those systems that does not use the GUI, and the systems can't be used
effectively from the command line. GNU/Linux is more modular, that is,
it's made up of many small, independent components that can be used or not
according to one's needs and preferences. One of these components is the X
Window system, or simply X.

This component is also sometimes called X11. Please note that ``X
Windows'' is not correct.

X itself is a means for programs to talk to your mouse and video card
without knowing what kind of mouse and video card you have. That is, it's
an abstraction of the graphics hardware. User applications talk to X in
X's language; X then translates into the language of your particular
hardware. This means that programs only have to be written once, and they
work on everyone's computer.

In X jargon, the program that speaks to the hardware is known as an X
server. User applications that ask the X server to show windows or
graphics on the screen are called X clients. The X server includes a video
driver, so you must have an X server that matches your video card.

The X server doesn't provide any of the features one might expect from a
GUI, such as resizing and rearranging windows. A special X client, called
a window manager, draws borders and title bars for windows, resizes and
arranges windows, and provides facilities for starting other X clients
from a menu. Specific window managers may have additional features.

Window managers available on a Debian system include fvwm, fvwm2, icewm,
afterstep, olvwm, wmaker, twm, and enlightenment. You'll probably want to
try them all and pick your favorite.