We come now to the X Window System — one of the most powerful and important software packages available for Linux. If you’ve ever used X on a Unix system before, you’re in luck; running X under Linux is almost no different from running it under Unix systems. And, if you’ve never had the occasion to use it before, never fear: salvation is at hand.
It’s difficult to describe the X Window System in a nutshell. X is a complete windowing graphics interface for Unix systems. It provides a huge number of options to both the programmer and the user. For instance, at least half a dozen window managers are available for X, each one offering a different interface for manipulating windows. By customizing the attributes of the window manager, you have complete control over how windows are placed on the screen, the colors and borders used to decorate them, and so forth.
Even if you have not heard about the X Window System yet, you may already have heard about KDE and GNOME. These are so-called desktop environments that provide a user-friendly work environment for your daily Linux work. We’ll cover these in great detail in the next chapter.
X was originally developed by Project Athena at MIT and Digital Equipment Corporation. The current version of X is Version 11 revision 6 (X11R6), which was first released in April 1994. Since the release of Version 11, X has virtually taken over as the de facto standard for Unix graphical environments.