The purpose of this chapter is to give readers some insight into and background knowledge of the history and eco system of GNU/Linux.


In 1984 and 1985 respectively, system programmer Richard M. Stallman (RMS), who was frustrated by the growing restrictions proprietary software imposed on him, founded the GNU project (GNU's Not Unix) with the aim to create a free Unix like operating system, and the Free Software Foundation (FSF) a foundation to promote free software. The word free doesn't mean free of charge, but free as in freedom. Specifically the following four fundamental freedoms:

• (0) The freedom to run the program, for any purpose.
• (1) The freedom to study how the program works, and change it to make it do what you wish.
• (2) The freedom to redistribute copies so you can help your neighbor.
• (3) The freedom to improve the program, and release your improvements (and modified versions in general) to the public, so that the whole community benefits.

The freedoms 1 and 3 require access to the source code of the program.


By the late 1980s the GNU project and FSF had created an almost complete free Unix operating system, but the kernel was causing problems.

Additionally the GNU project and the FSF had developed the philosophy of free software, as well as a legal framework including the most widely used free software licence the GNU General Public License (GNU GPL), which ensures that noone can redistribute the free software under non-free terms (copyleft).

In 1991, independentantly of the GNU project, then 22-year old Finnish university student Linus Torvalds decided to write a Unix kernel that he could use at home. Later that year he announced the first release on a newsgroup, using these now immortal words: "...I'm doing a (free) operating system (just a hobby, won't be big and professional like gnu)...".

The kernel was named Linux and soon it was licenced under the GNU GPL, and people started combining it with the GNU tools - a free Unix-like operating system was now reality, and many GNU/Linux distributions appeared - commercial and non-commercial.

Today Linus Torvalds lives in the U.S. and continues to lead development of the Linux kernel - but he's no longer alone, today over a thousand developers contribute code to the kernel every year - many of which are employed by large corporations, such as IBM, Intel, Novell and Red Hat.

Richard M. Stallman	Linus Torvalds

The term open source was created in 1998, by a group of people who wanted to distance themselves somewhat from the ideology and ethics of the free software movement and thereby make free software more appealing to commercial interests.

The software licences recognised by the Free Software Foundation and the Open Source Initiative are almost all the same, therefore there's very little difference between open source and free software in practice - the differences are almost exclusively on a philosophical and rhetorical level. To bridge the gap between the two camps the term "FOSS" (Free and Open Source Software) is often used.

SUSE was founded on September 2, 1992 in Germany, under the name Gesellschaft für Software- und Systementwicklung mbH (S.u.S.E. GmbH), meaning: "Software and System Development, Inc.". The first GNU/Linux distribution (S.u.S.E. Linux 1.0) was released in 1994 - making SUSE one of the oldest existing GNU/Linux distributions. Originally it was merely a German version of an American distribution called Slackware, but later SUSE has become one of the leading distributions. In 2003 SUSE was acquired by Novell and today development is distributed all over the world, but mainly located in Nuremberg, Germany, Prague in the Czech Republic and in the U.S.

In 2005 the openSUSE project was started with the goal of opening up development and involve the community more. openSUSE provides the base for Novell GNU/Linux products for enterprises - SUSE Linux Enterprise Server/Desktop and Novell Open Enterprise Server.

The GNU project mascot	The official mascot of Linux - the penguin Tux	The KDE mascot - the dragon Konqui	The SUSE mascot - the chameleon named Geeko

When the Linux kernel and the GNU tools and other free software components from "upstream" are bundled together to form a complete contemporary operating system, it's called a GNU/Linux distribution. Many distributions exist targetting different types of users and use cases - enterprises, home users, servers, desktops, multimedia centers etc. Some are commercial, others are fully based on the efforts of community volunteers. Besides bundling the software, distributors usually also integrate it, brand it, patch it, provide additional tools developed in-house and so forth. The existence of multiple distributions is only possible because the software components are free software of course.

This figure shows the ecosystem of upstream projects, distributors and end users.

Many developers are employed by large companies such as IBM, Sun Microsystems, Novell, Red Hat, Google, Mozilla Foundation, KDAB, Nokia, Intel, AMD, Canonical, Oracle etc. These companies usually have a business model of selling services around free software or selling hardware with free software installed on it. By using free software companies can share the development costs with others.

Also many people are paid to develop free software in other ways, via university work, government sponsorships, donations, students can be paid via the Google Summer of Code project, etc.

However there are also many, many people working on free software in their spare time for nothing. They can have many different motivations.

• They may need a feature or suffer a bug ("scratch your own itch").
• It builds their skills and network and creates job opportunities.
• Programming is fun and challenging.
• There's a lot of recognition and respect to be gained.
• You can work on projects of you own choosing, unlike at your day-job.
• They may think software freedom in itself is important enough to work for.
• They'll take part in an exciting world wide community.
• Etc.

Many people still perceive GNU/Linux as a small hobbyist operating system - and the marketshare on standard desktop PCs is quite small of course. Nevertheless a marketshare of about one percent, still adds up to many millions of people world wide. No truly reliable measure of the marketshare or total number of users is possible.

However GNU/Linux is very widespread in other areas. A very large share of web servers and other servers run GNU/Linux. Google and Yahoo build their entire infrastructures on GNU/Linux. GNU/Linux has been used everywhere from Antarctica to NASA using it in space. GNU/Linux is the preferred operating system for most of the worlds super computers. And GNU/Linux is used embedded in devices where people often don't even know it's there, such as mobile phones, PDAs, routers, harddisk recorders and more.