GNU/Linux is the Operating System. Is it right to say so? As you get into GNU/Linux and start working with it you will have the same feel. The common question which arises when one says GNU is “What is GNU?” GNU is a recursive acronym for “GNU is Not Unix”. Again the GNU in “GNU is Not Unix” expands to the same. It is not fair to say Linux instead we should refer to it as GNU/Linux. This is because Linux does not refer to the full fledged operating system; it refers only to the kernel which runs on the GNU/Linux operating system. A kernel could be compared to a human heart. A heart is an important part of a human system; similarly a kernel forms a main part of the operating system. It is a thin layer of software upon which the other system services run. Thus Linux is the kernel and GNU is the system which runs upon it and so we call the operating system as GNU/Linux.

Linux is a monolithic kernel, where in all the required services for a kernel are built on a single code or executable. This type of architecture ensures the entire kernel being loaded inside the memory when the OS is started, unlike a microkernel.

We know the fact that more than 3/4th of our entire universe contains water, similarly the e-world of today comprises of more than 3/4th of the servers which run on GNU/Linux. What made GNU/Linux so popular? It is due to the fact that it has good security, reusability, extendability, and customizability and above all it is free software which has the advantage of spending a very less amount or more clearly investing less for installation and maintenance of the servers. GNU/Linux is so flexible that we are free to customize it according to our hardware and our requirements, since we have the source code.

Why do we insist so much on free software? What is the need for it? We need to have a closer look at this. Consider a student who wants to study about the internals of an operating system. In order to do that, he needs the source code. In today’s scenario almost all proprietary operating systems give only their binaries or executables, and not the source code. It is very difficult or impossible to get the source code for such an operating system. Also we are puzzled about the architecture of the operating system. In order to know more about technology there must be sufficient understanding about it, which comes from similar technologies and their software. This is only possible with free software which provides four basic freedoms to its users.

• The freedom to run the program, for any purpose (freedom 0).
• The freedom to study how the program works, and adapt it to your needs (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 to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this.

This freedom which the free software community offers to its users is not only a boon for the students but also for all the developers world wide.

If this community had not been formed, consider the danger and difficulty we would face. A simple example is, if there is no freely available operating system then it would become impossible for an ordinary person to run his own computer. If a student wants to type his project report using a Word Processor then he must spend thousands to get his own licensed Word Processor from a company which sells proprietary software and then only he can use it, which is not possible for all. Then computers and its related subjects would become luxurious chariots which the rich people can only ride on. This is the prime reason why free software has become popular.

Richard M Stallman is the person who is considered as “The Father of Free Software Community”. When he was working in the MIT labs, the most stable and widely used operating system was UNIX. But as time passed on the developers of UNIX wanted to make it proprietary. Stallman on seeing this was alarmed at the cost that people must pay for such an activity. So he thought of developing an operating system and he started the GNU project which focused on developing the system necessary for running upon a kernel. Their initial idea was to develop a kernel which will be “THE BEST”. So they started working on HURD, which would serve the purpose. But in the early 90’s a large collection of software necessary to run on a kernel was ready, but unfortunately the Hurd kernel had not yet been completed. This was when Linus Torvalds came with his kernel Linux which he dedicated to the free software community. Then they decided to use the Linux kernel and run the GNU system and release the GNU/Linux operating system.

Organizations such as Debian, Redhat and many more came and started collecting the scattered software packages all over the world developed by many free software enthusiasts as a part of the GNU project. They took a suitable Linux kernel release, combined it and released as a full fledged, working user friendly operating system which is the current heart throb of the world.

This is the history of GNU/Linux and its birth into this world. To get more information on the philosophy and the GNU project, visit www.gnu.org and www.fsf.org