contributor's developments. To protect the author's copyright, as well as to guarantee the free
use of derivatives of the GNU work, the FSF developed the GNU General Public License (GPL).
Some products available under the GNU Public License, such as EMACS or the GNU C
Compiler became widely used, but only the introduction of Linux under the GPL pushed the idea
of free software to a new level of interest. With Linux's growing market share, the business
world took notice of the free software movement. The restrictive GNU public license with its
idealistic view, however, led to the development of other public licenses that seemed more
appropriate for business purposes, while taking advantage of the ideas of free software.
The introduction of these other licenses, such as the BSD, MIT X, Mozilla, or Artistic licenses,
increased the confusion about the meaning of free software and Open Source. Therefore,
community members developed a specification called The Open Source Definition in 1997.
This specification establishes guidelines for software licenses to be considered Open Source .
The definition is available at
Donald K. Rosenberg, M&T Books; Open Source: The Unauthorized White Pages, Chapter 1
and 3; 2000;
Bruce Perens, O'Reilly & Associates, Inc.; Open Sources: Voices from the Open Source
Revolution: Essay 11: The Open Source Definition; 1999
2.2 Linux Overview
2.2.1 Introduction to Linux
Linus Torvalds created the Linux operating system as a personal project in 1991 (in Finland),
out of the desire to learn and understand the 386 processor and Unix based operating systems.
It was released free of charge to the public for everyone to make improvements under the terms
of the GNU General Public License.
Since then, Linux has grown into a major player in the operating system market, thanks to the
contribution of hundreds of developers all over the world and the coordinating efforts of Linus
Torvalds. It has been ported to run on a variety of architectures including Compaq s Alpha,
Sun s SPARC, and Motorola s PowerPC chips. The term Linux technically only refers to the
kernel (the core of the operating system).