Since this my first post in this blog ,I decided that it will be about open source .
why open source specially ?! ! ..... Well , in my opinion open source is a matchless approach that changed whole the IT world , made it easier and in Constant Evolution . so ,now we will deepen slightly in open source software .
In abstract view ,we will see that Open source software, Free software or software libre is any software whose code is published and made available to the public , so anyone can see the code , see how it is made , enabling any one to copy , modify and redistribute the source code without paying any royalties or fees , without restrictions or with minimal restrictions only to ensure that further recipients can also do these things .
The main characteristic that distinguish open source approach from others that it is free !! ........ yes , it is free , anyone can study , copy , distribute , change and improve the software without paying anything . That besides better quality , higher reliability , more flexibility , and an end to predatory vendor that made open source products much better from closed source ones .
Now , we came to open source freedoms : the program's users have these four essential freedoms :
* The freedom to run the program, for any purpose (freedom 0).
* The freedom to study how the program works , and change it to make it do what you wish (freedom 1). Access to the source code is a precondition for this .
* The freedom to redistribute copies so you can help your neighbor (freedom 2).
* The freedom to improve the program, and release your improvements (and modified versions in general) to the public , so that the whole community benefits (freedom 3). Access to the source code is a precondition for this too .
A program is free software if users have all of these freedoms. In order for the freedoms to make changes, and to publish improved versions, to be meaningful, you must have access to the source code of the program . Therefore , accessibility of source code is a necessary condition for free software . Then , The freedom to run the program means the freedom for any kind of person or organization to use it on any kind of computer system, for any kind of overall job and purpose, without being required to communicate about it with the developer or any other specific entity .
Free software has become the foundation of a learning society where we share our knowledge in a way that others can build upon and enjoy .
The free software movement was started in 1983 by computer scientist Richard M. Stallman, when he launched a project called GNU, which stands for “GNU is Not UNIX”, to provide a replacement for the UNIX operating system - the Operating System Prevailing time - a replacement that would respect the freedoms of those using it .
The goal was to bring a wholly free software operating system into existence. Stallman wanted computer users to be free to study the source code of the software they use, free to modify the behaviour of the software, and free to publish their modified versions of the software. This philosophy was published in 1985 as The GNU Manifesto . Richard Stallman said: "Free software is a matter of liberty, not price. To understand the concept, you should think of 'free' as in 'free speech', not as in 'free beer" .
Then in 1985, Stallman started the Free Software Foundation (FSF) a nonprofit with the mission of advocating and educating on behalf of computer users around the world and wrote the GNU General Public License (GNU GPL) in 1989 . In the mid- and late-80s, FSF hired software developers to write the software needed for GNU. At its peak it had 15 people on its staff .
FSF also holds the copyrights for some GNU software packages. Most GNU packages are licensed under the GNU General Public License (GNU GPL), while a few use the GNU Lesser General Public License (GNU LGPL), and a still smaller amount use other free software licenses.
GNU would be mostly compatible with Unix,( The Unix operating system was conceived and implemented in the 1960s and first released in 1970 ) which was a popular proprietary operating system at that time .
Naming : The FSF recommends using the term "free software" rather than "open source software" because, they state in a paper on Free Software philosophy, the latter term and the associated marketing campaign focuses on the technical issues of software development, avoiding the issue of user freedoms. "Libre" is used to avoid the ambiguity of the word "free" .
Linus Torvalds has said that if the GNU kernel had been available at the time (1991), he would not have decided to write his own . but Torvalds began to work on a non-commercial replacement for MINIX -a small clone of UNIX . He became the world's most famous computer programmer and the founder and coordinator of Linux, the Unix-like operating system which we will talk about it later .
There are now many variants or 'distributions' of this GNU operating system using the kernel Linux . GNU's kernel isn't finished , so GNU is used with the kernel Linux . The combination of GNU and Linux is the GNU/Linux .Sometimes this combination is incorrectly called Linux . There are many variants or “distributions” of GNU/Linux .
Today , there is a wide range of open source software available, and new projects are being started all the time . Certainly the impressive list of industry heavyweights now supporting Linux open source operating system including Sun, Oracle, and IBM have given credence to this view. Open source code evolves through community cooperation. These
communities are composed of individual programmers as well as very large companies . Some
examples of open source initiatives are Linux kernal , Eclipse , Apache , Mozilla , the BSD , GNU/Linux operating systems , the GNU Compiler Collection and C library, the MySQL relational database , the Apache web server , emacs text editor , the X Window System graphical-display system , the OpenOffice . org office suite and the TeX and LaTeX typesetting systems and various projects hosted on SourceForge .
Today, free software is available for just about any task you can imagine .
