Linux is short for "Linus' Unix," with the short "i" sound preferred, after the Swedish pronunciation of "Linus."

Linux is a Unix-like operating system designed to give personal computers a free, or nearly free alternative to more complex Unix systems. It was developed by Linus Torvalds at the University of Helsinki in Finland. More specifically, Torvalds developed the kernel -- the central part of the Linux system -- the rest of the complete system involves components developed as part of the GNU Project.

Linux is nothing more than a kernel, meaning it's not technically an operating system. Rather, the software entity that controls the physical aspects of the machine, such as memory allocation and software drivers.

The X server is the layer of the Linux operating system that provides the Graphical User Interface (GUI) for the users desktop.

There are many desktop environments (DE) you can run atop the X server. Popular choices are Gnome, KDE and BlackBox.

Each DE has it's own options and features to offer. Each one of these can be customized to suite your tastes. Everything from wallpapers to keyboard bindings can be controlled.