Introduction

An “open source” software is a software whose source-code, that is the sequence of instructions that forms the program, is openly available to anyone and cannot be privately appropriated and sold or rented. The development of open source software, also called “free software”, is based on the contributions of voluntary and benevolent developers. This within a cooperative mode of organization that largely draws its efficiency from the organization and communication commodities which have arisen from the Internet structure.

The star product of free software today is the operating system Linux that was designed from the initial kernel conceived by a young programmer called Linus Thorvald, then developed and progressively improved through a cooperative and open process of coordination. Linux, inspired by the basic concepts of Unix, has been mainly dedicated to implementation on micro-computers but in fact has a wider scope for potential uses on larger systems. Many other products are now available from specialized suppliers or freely downloadable on the Internet: web servers, office applications, scientific programs, image processing … Some of them have achieved very important market shares, like Apache which holds first place in the field of web servers; the main tools for the Internet also belong, in their majority, to the open source world.

The cooperative mode of development of free software, often called the “bazaar” model (Raymond, 1998), gives to any programmer the possibility of making any improvement or change that might be useful for him.