What is LINUX

A very popular open source operating system that runs on a variety of hardware platforms including x86, Itanium, PowerPC, ARM and IBM's entire product line. Based on many design principles used in the Unix operating system, and thereby often called a "Unix clone" or "Unix variant," Linux is widely deployed as a server OS and as an embedded OS. For example, Linux runs in most of the servers on the Internet and in countless appliances and consumer electronics devices (see embedded Linux). In the desktop market, Linux has nowhere near the same penetration; however, it gains ground slowly and steadily.

Linux is a multitasking, multiuser operating system that is known for its stability. Although modified by numerous people, its robustness stems from its Unix-like architecture that keeps peripheral software components isolated from the core software (the kernel).

Licensed under the GNU General Public License (GPL), Linux is the flagship product of the open source community (see open source and GNU General Public License). Numerous groups work on their own flavor of Linux, modifying it for various purposes, and several commercial organizations "distribute" Linux for a fee (see Linux distribution). Linux is an outstanding success because it embodies the major features of Unix in a modifiable open source package, including its compliance with the POSIX standard (see POSIX).

Not Just One User Interface
Linux employs the X Window rendering system for displaying data on screen. Because X Window provides only the basic window creation, it relies on third-party user interfaces to provide the window borders and buttons, menus, icons and desktop that users see and manipulate. KDE and GNOME are two of the most popular (see KDE and GNOME). A Linux distribution may include more than one user interface, all of which appear on screen somewhat similar to the Windows and Mac interfaces. See X Window.

From Minix to GNU/Linux
In 1990, Finnish computer science student Linus Torvalds created the Linux kernel (see kernel). He was inspired by Minix, a popular classroom teaching tool that was very close to Unix. Although Torvalds created the kernel, many of the supporting libraries, utilities and applications came from the GNU Project, which is why Linux is often designated as GNU/Linux. Over the years, a huge number of programmers have contributed to the GNU/Linux system. For more information, visit www.linux.com and www.gnu.com.

Torvalds maintains the official Linux kernel, which continually integrates patches and enhancements from the Linux community. For more information, visit www.kernel.org.

Linux Is Really "Lee-Nooks"
If you lived in Finland, you would say "lee-nooks" because Linus is pronounced "lee-noose." Since the English pronounce Linus as "line-iss," some call it "line-icks." More common is "lynn-icks," which splits the difference. No matter how you say it, Linux is very popular. See embedded Linux, KDE, GNOME, X Window, Lintel, Minix, Ubuntu, SuSE Linux, UnitedLinux, GNU, open source, Linux Foundation, Trinux, SCO and Red Hat.

A Lot of Server
This innovative Linux appliance from Net Integration Technologies packs a lot into a small box. Running the Nitix OS, it includes built-in Web, e-mail, VPN and remote access servers, a firewall and file and print services for Windows, Mac and Linux. It connects two ISPs to the LAN and provides automatic failover if one goes down. (Image courtesy of Net Integration Technologies Inc., www.nitix.com)

A Linux Laptop

In 2005, System76 was the first hardware vendor to offer packaged Linux laptops, desktops and servers. This laptop comes with the Ubuntu version of Linux and a variety of applications that most people use all the time (see Ubuntu). (Image courtesy of System76, www.system76.com)

The Penguin Is Everywhere!
The Linux mascot happens to be a penguin, and the penguin is everywhere, even on an iPod. iPodLinux is an open source project that enables the iPod to boot up into a tiny version of Linux. (Image courtesy of the iPodLinux Project, www.ipodlinux.org)