Linux, a free system | INA Global

Linux, a free system

Article  by  Nicolas WEEGER  •  Published 29.10.2010  •  Updated 31.05.2012
Copyright Larry Ewing and Simon Budig
Created mostly by volunteers during the free software movement, Linux distributions are an alternative to Windows or Mac OS. Offering numerous tools for both private and professional users, they still remain rather unknown to the public, though not for want of trying.

Summary

Introduction

The Linux name is not widely known, especially compared with software giants such as Microsoft and Apple. Yet this system, whose distributions play a substantial role in the structure and development of the Internet, as well as the software movement that it is a part of, has serious repercussions in many domains.
Back to summary

The history of Linux

In 1983, Richard Stallman launched the GNU project (a recursive acronym for “GNU’s Not UNIX”) that aimed to create an operating system that would be completely free [+] NoteIn the sense that users can do what they want with the software, including redistribute it, modify it, etc.X [1] and compatible with UNIX. Different tools such as compilers* and basic libraries* were created and work began on the HURD kernel that became the heart of this operating system.
 
On 26th August 1991, Linus Torvalds, a Finnish student, posted the very first version of an operating system resembling MINIX [+] NoteA system that resembles UNIX.X [2] and that was capable of using the GNU compiler onto the group discussion network Usenet [+] NoteSee http://en.wikipedia.org/wiki/Usenet for a more complete definition of Usenet.X [3]. He worked on this project simply for pleasure and without any particular ambition.
 
With the HURD kernel taking longer than projected [+] NoteIt is still today in the process of being developed.X [4], Linus Torvalds, along with many other contributors, worked on improving the first version of the Linux kernel, adding support for hardware components and applications and making sure that the GNU tools functioned correctly on this kernel.



Volunteers rapidly constructed Linux distributions [+] NoteSome people think that it should be talked about in terms of a “GNU/Linux distribution” as most of the basic tools come from the GNU project. See http://www.gnu.org/gnu/why-gnu-linux.htmlX [5], from sets of software to form a coherent system that is ready to use, so they no longer had to search for software from disparate Internet sources.
Back to summary

Economic aspects

Most of the software that forms a Linux distribution is free software, which can be modified at will and distributed either free of cost or sold.
 
An overwhelming majority of contributors are unpaid volunteers [+] NoteMany contributors simply want to participate in the project for their own needs or pleasure, the fact that their work will be benefited from by others a simple side effect.X [6], this doesn’t mean that certain contributors can’t be officially employed by commercial companies. Linus Torvalds himself is employed to work on the kernel* by the Linux Foundation.
 
All the big names of the computer world such as IBM, Intel, Oracle and Novell support the Linux kernel and its distributions. This support, in addition to their use of Linux distributions which is a mode of support in itself, sometimes comes in the form of making resources available that may aid the improvement of the kernel*, which as a consequence is now written for the most part by salaried workers [+] Note"75% of Linux code now written by paid developers", http://apcmag.com/linux-now-75-corporate.htmX [7].
 
 The distributions themselves are largely managed by volunteers. There are hundreds of distributions in existence that target a varied public: the smallest distribution possible, ones for specific servers, ones for the mass public, ones that are vulnerable to attacks that act as training software for computer security students, etc.
 
Distributions that are managed by commercial entities, such as Mandriva and Redhat also exist. They sell DVDs, or other hardware such as USB keys, that contain a Linux distribution (the components of which are free and can be redistributed at will) and offer a service for that distribution, notably commercial support. Canonical, founded by Mark Shuttleworth, edits the Ubuntu distribution, which aims to promote Linux to the mass public. Mandriva’s sale figures were around 4 million Euros in 2007, those of RedHat were almost 750 million dollars in 2009  and those of Canonical were at 30 million dollars according to Mark Shuttleworth.
 
The market share of Linux distributions is difficult to estimate. There aren’t any global sales figures to go by (as in the majority of cases it is not sold). The amount of downloads would give an indication but only within limits: one downloaded distribution can easily then be installed on many computers.
 
Regarding the servers’ market, Steve Ballmer, CEO of Microsoft, stated in September of 2008 that Linux was used on around 60% of servers.
 
Regarding the personal computer market, Linux can only claim a small penetration percentage, estimated to be between 1 and 5%. For example, in June 2010 86% of internet users on Wikipedia and its sister sites were using Windows, with 7% using Mac and only 2% on Linux.
 
In order to reduce final costs or to attract the contributor community, many large computer companies provide or have provided in the past computers equipped with Linux distributions rather than Microsoft Windows. Dell is one that officially supports certain Linux distributions. Wal-Mart, the brand name linked to mass distribution, also promoted computers pre-installed with Linux over several months [+] NoteSee, for example http://www.wired.com/gadgetlab/2007/10/200-everex-gree/X [8]. It is also interesting to note that, for many years now, computer distributors have been continuously pressured by Microsoft not to offer anything other than Windows.
 
Even if the sources are free, software logos and brands are generally protected in order to avoid any improper usage. In the States, Linux is a registered trademark of Linus Thorvalds, Debian is a registered trademark of Software in the Public Interest and Inc. and Ubuntu is a registered trademark of Canonical.
Back to summary

What is a Linux distribution

A Linux distribution is a set of software, free for the most part [+] NoteOne of the major elements that is often not free is the pilot for the graphics card, especially those from NVIDIA®. There are alternative ones around that would be free but they won’t necessarily be as good.X [9], that form a complete operating system. This would, for the most part, be comprised of a server, an office-based software system and a graphic interface, but this can also be any other combination. One of its strengths is that there is a distribution to suit any number of specific needs, from an equivalent to Microsoft Windows to the completely exotic.
 
A major advantage of a distribution destined for the mass public is that it will provide all basic necessary tools during the installation process so that the user is not required to install the software he needs himself.
 
Distributions generally have a system of packets*. A program called “packet management*” allows the user to install and update, via the Internet, any software available within its distribution. This allows for a centralisation and gives Linux a unique tool [+] NoteIt is of course also possible to install applications without using the packet management tool. The user then becomes responsible for all updates.X [10], in contrast to systems such as Microsoft Windows and Apple Mac OS where each program [+] NoteExcept, sometimes, Microsoft® or Apple® programs themselves that can often be updated using the same mechanism as the system itself.X [11] has its own individual updating system.
 
The distributions use source codes written by volunteers for other programs, such as Firefox or OpenOffice.org. This packet will then be redistributed to all users of that particular distribution.
 
The numbering system for the different versions and the updating strategies vary enormously from distribution to distribution. Some, for example, are numbered according to the date they were created (2010.05 for the Arch Linux distribution for example).
 
One strategy employed by Debian (amongst others), which is one of the oldest distributions still in use, is to have different versions of itself: a stable version (Debian’s current stable version is called “Lenny” [+] NoteDebian uses the names of Toy Story characters for its versions.X [12]) uses previous stable versions that are often a few months or even years old and have therefore been rigorously tested, with all major bugs having been corrected before they were made available; they also have an “unstable” version (the current one is called “Sid”) that contains more recent packets that are still in the process of being tested so that they can then in turn become part of a future stable version.
 
When a bug is found, the distribution can either send it back to the original project to be fixed or can correct it itself, sending it back to the original project afterwards.
 
Each distribution has its own website, with information, forums, discussion boards and, of course, communities of users and developers. Contributors sometimes collaborate and cross-check their work, especially research.
 
One of the weaknesses of Linux distributions, which is also however one of their strengths, is their extreme variety. Even if standardising rules do exist in order to render certain aspects consistent [+] NoteNotably the Linux Standard Base, http://www.linuxbase.org/X [13] (the directory structure, etc.), the huge amount of available combinations (regarding libraries, packets management, versions used, etc.) make its difficult to provide a universal support for programs, especially for proprietary ones that need to be tested on thousands of different combinations. These tests cost a considerable amount, which combined with the small proportion of Linux users discourages many companies from providing versions for this system.
Back to summary

The world of Linux

Linux, its kernel as well as its distributions, is highly associated with the movement concerning free software. The associated philosophy is one that defends access to software source codes with rights to read, modify and redistribute. 
 
This is highly contradictory to those programs deemed proprietary (as are most of those linked to Microsoft and Apple), which users cannot redistribute at will nor can they access the sources.
 
The motivations of these defenders of free software are diverse. Some have purely practical reasoning, claiming that distributable and reusable sources allow for better software to be developed in the end (no need to reinvent the wheel, if a software component works well why not use it), whilst others consider it to be purely a question of philosophical principles.
 
The world of free software has expanded into other domains such as art and knowledge as well. Wikipedia is the best example of an attempt to promote the freedom of knowledge. The Creative Commons Licences provide users’ licences based on authors’ rights, which allow for modification and redistribution of artistic works in a similar fashion to free software. These movements have repercussions in the legal domain as they touch upon the different debates that are constantly taking place surrounding authors’ rights and intellectual property.
 
Another point that incites debate amongst the defenders of free software is the definition of “freedom” when attached to sources. For the supporters of “BSD” style licences, free sources should be reused even in proprietary software, therefore compromising the very nature of them. For those in favour of “GNU” style licences, the sources should stay completely free including in their final usage, which would forbid it from being used with proprietary software. Some people speak of a viral nature to describe the latest licences, as they “contaminate” the code that they are concerned with. This sometimes puts off commercial entities who don’t want to risk “wrongfully” using the GPL* code and find themselves tangled up in legal issues.
Back to summary

Conclusion

Today, Linux distributions are a valuable alternative to such operating systems as Windows or Mac OS. In the servers domain, they have managed to capture a large market share. However, with regard to the mass public computer market, they have barely scratched the surface. This is partly due to the simple laziness of users who are complacently satisfied with their Windows or Mac OS operating system but it is also due to a lack of information and advertisement surrounding Linux and its distributions.
 
However, all of those in favour and support of Linux don’t necessarily want it to break into the mass market with some fearing that this will result in a decrease in the quality of distributions and others, on a more selfish level, are simply happy to have found a system that works for them, not caring if other users benefit from it or not.
Back to summary

Examples of Linux distributions

  • Debian, based on a system of pre-compiled packets
  • Gentoo, based on the idea that each user compiles the programs with their own optimisation options
  • Slackware, one of the first ever distributions and the oldest one still in use
  • Damn Small Linux, a distribution that takes up the least amount of space possible
  • Damn Vulnerable Linux, a vulnerable distribution built as a training tool for computer security students
Back to summary

Examples of free softwares

  • OpenOffice.org, office software package with which one can handle texts, make graphs, create presentations
Back to summary

Glossary

  • Compiler: a program that transforms source code into object code, which is written in computer language and therefore more accessible for the computer
  • Library: the group of functions that are shared by all different programs
  • Kernel: the heart of any operating system, in charge of communication between the different components
  • Packet: software created to be used on a specific distribution, as well as on associated metadata (inter-dependence of different packets, incompatibility of certain packets, keywords, etc.)
  • Packet Management: software specific to one distribution allowing the user to install, update and delete packets* from this distribution on its operating system.
Back to summary

Selective references

  • The GNU Manifesto, by Richard Stallman, in which he describes why he created the GNU project and its objectives.
  • The Cathedral and the Bazaar, an essay by Eric Steven Raymond that compares different development methods of both proprietary programs and free software.
Back to summary

Screenshots

Images taken from KDE:
 


 

Back to summary
  • 1. In the sense that users can do what they want with the software, including redistribute it, modify it, etc.
  • 2. A system that resembles UNIX.
  • 3. See http://en.wikipedia.org/wiki/Usenet for a more complete definition of Usenet.
  • 4. It is still today in the process of being developed.
  • 5. Some people think that it should be talked about in terms of a “GNU/Linux distribution” as most of the basic tools come from the GNU project. See http://www.gnu.org/gnu/why-gnu-linux.html
  • 6. Many contributors simply want to participate in the project for their own needs or pleasure, the fact that their work will be benefited from by others a simple side effect.
  • 7. "75% of Linux code now written by paid developers", http://apcmag.com/linux-now-75-corporate.htm
  • 8. See, for example http://www.wired.com/gadgetlab/2007/10/200-everex-gree/
  • 9. One of the major elements that is often not free is the pilot for the graphics card, especially those from NVIDIA®. There are alternative ones around that would be free but they won’t necessarily be as good.
  • 10. It is of course also possible to install applications without using the packet management tool. The user then becomes responsible for all updates.
  • 11. Except, sometimes, Microsoft® or Apple® programs themselves that can often be updated using the same mechanism as the system itself.
  • 12. Debian uses the names of Toy Story characters for its versions.
  • 13. Notably the Linux Standard Base, http://www.linuxbase.org/
Would you like to add or correct something? Contact the editorial staff