Introduction

Linux is an operating system that was initially created as a hobby by a young student, Linus Torvalds, at the University of Helsinki in Finland. Linus had an interest in Minix, a small UNIX system, and decided to develop a system that exceeded the Minix standards.

He began his work in 1991 when he released version 0.02 and worked steadily until 1994 when version 1.0 of the Linux Kernel was released. The kernel, at the heart of all Linux systems, is developed and released under the GNU General Public License and its source code is freely available to everyone.

It is this kernel that forms the base around which a Linux operating system is developed. There are now literally hundreds of companies and organizations and an equal number of individuals that have released their own versions of operating systems based on the Linux kernel. More information on the kernel can be found at our sister site, LinuxHQ and at the official Linux Kernel Archives. The current full-featured version is 2.6 (released December 2003) and development continues.

“Linux is gaining ground in the mobile-handset space due to the benefits it brings to manufacturers and operators and eventually also to the end consumers,” said marketing director, Mobile & Personal Business Unit, NXP Semiconductors.
“Linux motivates developers to generate and share new vibrant media applications such as games, advanced music players and intuitive TV-on-mobile, offering greater benefits to the end user and allowing for differentiation for both manufacturers and operators.”

“The Open Source platform supports interoperability across the various brands of handset devices,” said managing director, Purple Labs, “Linux lends itself well to modular design by offering OEMs a flexible and powerful operating system, resulting in the easier development of new applications. Today’s end-users demand feature-rich, compact and cost competitive handsets, but will not compromise on core features such as low-power consumption and high performance, and the Nexperia cellular system solution 7210 with Linux easily enables manufacturers to meet these needs.”

If you have used FreeBSD or another Unix-like operating system like you can adapt very quickly to Linux. Or, if Linux is your first exposure to Unix-like operating systems, you'll find a wide variety of documents in our Knowledge Base and on the web to get you started.

What is Linux?

Linux is a UNIX-based operating system originally developed as for Intel-compatible PC's. It is now available for most types of hardware platforms, ranging from PDAs (and according to some reports, a wristwatch) to mainframes. Linux is a "modern operating system", meaning it has such features as virtual memory, memory protection, and preemptive multitasking.

Linux is built and supported by a large international community of developers and users dedicated to free, open-source software. This community sees Linux as an alternative to such proprietary systems as Windows and Solaris, and as a platform for alternatives to such proprietary applications as MS Office, Internet Explorer, and Outlook

As a result of this community, there is a very large collection of free software available for Linux. There are graphical environments (GUIs), office applications, developers' tools, system utilities, business applications, document publishing tools, network client and server applications -- the list goes on

The best part of this community is that all code is open. This means there is no barrier to entry; for any given problem, there are generally several applications that solve the problem. These applications can also borrow the best parts from each other to become even better. An excellent example of this is Galeon. Galeon is a web browser which took Mozilla's web page rendering engine and integrated it with a GTK frontend (instead of Mozilla's normal frontend).

Linux specifically refers to the Linux kernel. However, the kernel is useless without a set of tools and applications to run on the kernel. Linux is most commonly distributed with this toolset and a collection of applications in what is called a "distribution". The most common are Redhat, Mandrake, Suse, and Debian. Distributions differ in three basic ways: the process for installing the distribution, the applications available, and process for installing and managing these applications.

Linux Versions

If there are so many people working on it. There's likely to be many Linux versions too. Many companies working on Linux have come up with what are called Linux distributions.

There are Linux versions that are compiled and packaged and released with various additional software. The popular distributions or destroys include Red Hat Linux Mandrake Linux, Corel Linux SUSE Linux and Debian, it's just like having different flavors of ice cream. True to the spirit of open source, if you download the distro from the company's Website, it is free for use. But the distros are usually quite huge.

If you are getting the distorts from the company, be ready to pay up a tiny bit. Companies compile the packages, make installation hassle free, bundle applications, add a manual, and extend any support you need. So they charge a fee for all this.

Why use Linux?

Reasons to Install Linux

• Configurability
• Convenience
• Stability
• Community
• Freedom

Configurity:- Linux distributions give the user full access to configure just about any aspect of their system. Options range from the simple and straightforward (for instance, changing the background image) to the more esoteric (for instance, making the "Caps Lock" key behave like "Control"). Almost any aspect of the user experience can be configured

Linux also allows the user to automate just about any task. Advanced scripting and high-level programming are standard features. Most operations are accessible via these scripting options. Finally, Linux offers the ultimate in configurability: the source code, to be modified as you see fit.

Convenience:- While Linux takes some effort to get set up, once it is set up, it is surprisingly low-maintenance. Package management can simply be a matter of running two commands in the shell. Linux also offers complete remote access. This allows the user to act exactly as if she is sitting at that computer's desk, potentially across town or on the other side of the world.

Stability:- Linux is based on the UNIX kernel. It provides preemptive multitasking and protected memory. Preemptive multitasking prevents any application from permanently stealing the CPU and locking up the machine. Protected memory prevents applications from interfering with and crashing one-another.

Linux and related tools are also open-source. This means that the source code is available for the public to view. There are literally hundreds, if not thousands, of developers working on the various pieces of Linux. In this open development process, bugs are fixed very quickly. In addition, bugs are fixed immediately, instead of waiting for the next major release. It certainly helps that the people who develop Linux and associated tools use their programs every day.

Community:- Linux is part of the greater open-source community. This consists of thousands of developers and many more users world-wide who support open software. This user and developer base is also a support base.

In Rice, there is the Rice Linux Users Group (the group who are bringing you this class). We hold regular meetings where people can bring up their Linux problems. There is also the newsgroup rice.comp.linux, where questions can be asked or problems laid out any time, day or night. This newsgroup is mirrored to the RLUG-discuss mailing list, for RLUG members who don't have access to Rice newsgroups.

Worldwide, the Linux community is even greater. There is a mailing list for just about every project or piece of software in active development -- if you have a question about a program, who better to ask than the person who wrote it? There are also newsgroups and web pages which have collectively with the mailing lists probably addressed every problem someone new to Linux has encountered several times over.

Freedom:- Linux is free. This means more than just costing nothing. This means that you are allowed to do whatever you want to with the software. This is why Redhat, Mandrake, and Suse are all allowed to sell their own distributions of Linux. The only restriction placed on Linux is that, if you distribute Linux, you must grant all the privileges to the code that you had, including providing the source. This prevents a corporation from using the Linux kernel as the basis for their proprietary operating system.