'''X''' usually refers to the '''X Window System''',
currently at Version 11  Revision 6. Hence often also
refered to as '''X11''', or '''X11R6'''.

This X11 is not to be confused with [MacOS X] which is also often just called "X" by Mac afficionados.

[Xlib] is a higher level interface used by most applications to communicate using the X protocol.  Tk emulates many Xlib functions on platforms that don't have X11.

References

   * http://www.x.org        - X in general
   * http://www.xfree86.org  - XFree implementation of X (servers)
   * news://comp.windows.x
   * http://www.faqs.org/rfcs/fyi/fyi6.html - simple overview of papers/standards available (perhaps a bit outdated, as it was written in 1991)
   * http://www.faqs.org/rfcs/rfc1013.html - X protocol
   * http://www.xfree86.org/current/specindex.html - XFree collection of specification documents
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The symbol ''x'' is often used by mathematicians, scientists and engineers to refer to the component of a vector that is parallel to the first axis of the coordinate system (the horizontal one - [RS] remembered the difference in school by considering that Y has a vertical bar, while X hasn't ;).

It is also sometimes taken to just refer to something unknown, as in "With added Factor X for extra cleaning power!!!"
(Like much of advertising, this is of course nonsense; factors are not things you add, but things by which you multiply!)


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[[It probably would be useful to tell all kinds of things about X, 'bout how it's much despised in
some circles, how XFree86 is only one nexus for innumerable coups and counter-coups, ...]]
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[[
[Category Glossary] |
[Category GUI] |
[Category Desktop] |
[Category Application]
]]