What is X?
Everyone likes pretty pictures. The newsagent’s stand is now crowded with glossy magazines, roadside advertisements glare out at you as you drive along the freeway, you see a wondrous mosaic as you look at all the packaging on supermarket shelves. Television long ago replaced the radio as standard home entertainment and the fact that you cannot judge a book by its cover doesn’t prevent the vast majority of the human population from doing so. The same applies to computers now. The GUI (Graphical User Interface) or “windows functionality” has become part of the machine that everyone now takes for granted.
Any home or client system software provider, free or otherwise, that wants to be taken seriously has to provide a graphical user interface (GUI) as their prime method of user interaction. Microsoft include theirs as part of the main system, or kernel, as do many other system providers. Most GNU/Linux distributions include it in the default install. However, with GNU/Linux and other POSIX operating systems, the GUI infrastructure is not part of the kernel but a separate program with the mystical name of “The X Window System”. It calls itself “X11 Release 6” and everyone else simply knows it as “X”. There’s a lot more to this X than meets the eye, it has attributes and powers that are not well known and can do things that other windowing systems cannot. What is this X? What amazing super-GUI powers does it have? This article attempts to tear off its mask and reveal all.
What is X?
A more appropriate question to “What is X?” is “What is X not?”. X is not actually a GUI.