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 

http://www.opensource.org/osd.html

. 

Selected References 

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).  

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