Red Hat Linux and the GPL

You will find out more about the origins of Linux later on in the course. For now, we will discuss how Red Hat came to be, and why the role of the Free Software Foundation, OSS (Open Source Software), and the GNU GPL are so important to the Linux community.

Open Source Software (OSS) means that the source code as well as the binary (the actual program you run) is accessible and distributed freely.
Free software may cost money and may be covered under a public license, the most common of which is the GNU Public License (GPL). Open source describes practices in production and development that promote access to the end product's source materials. Some consider open source a philosophy, others consider it a pragmatic methodology. Before the term open source became widely adopted, developers and producers used a variety of phrases to describe the concept. Opening the source code enabled a self-enhancing diversity of production models, communication paths, and interactive communities. Subsequently, a new, three-word phrase "open source software" was born to describe the environment that the new copyright, licensing, domain, and consumer issues created.

The license for Red Hat Linux is the GPL. If you want binaries from Red Hat, you will need to subscribe to their distribution service, Red Hat Network, also known as RHN. That said if you know someone who has Red Hat binaries, they can redistribute them to you for free. Red Hat simply chooses not to distribute binaries for no cost. This is permissible under the GPL. If you want a binary distro that you do not have to pay for, then as others have said above, try CentOS or Fedora. You can download the src at ftp.redhat.com e.g.:

https://developers.redhat.com/products/rhel/download

As you may know, Linux was first introduced by Linus Torvalds in 1991 as a "free" operating system. Torvalds began development of the Linux kernel while he was a student at Helsinki University, and he continues to maintain it today. Red Hat Software distributes Torvalds' version of the Linux kernel.

OSS can be freely seen, modified, and improved by anyone who uses it. Linux was created this way. So was the Internet a technology owned by no one, and to which everyone can contribute. Linux is considered free software, but it is not in the public domain. It adheres to the GNU General Public License (GPL), which says that it can be freely distributed or even sold, but it must always be accompanied by its source code as well as the GNU GPL.

The concepts of free software that costs nothing and free software whose source code everyone can view are often confused. OSS is a more recent phenomenon than free software. As it is currently defined by the GNU GPL, "free" software does not mean it costs nothing. On the contrary, if you sell software covered by this license, you have to make the source code available to the buyer for free (or for the cost of the materials it is shipped on).

The GPL allows anyone to modify the source code covered by the license, and to distribute derived products as long as the original source is made available. OSS gives users the ability to modify the code to suit their own needs, which is not possible with proprietary software code.
OSS is the reason behind the amazing speed at which Linux development occurs. OSS is extremely flexible. Depending on how it is used, there are zero licensing costs, it has fast bug fixes, and it is rich with feature enhancements.

Linux consists of a worldwide community of developers who have written drivers, features, and new functions all working under the GNU GPL. Since 1991, Linux has developed into a full-blown computing environment with a worldwide installed base of millions of users.

The purpose of this document is to help developers (and their managers) work with the development community with a minimum of frustration. It is an attempt to document how this community works in a way which is accessible to those who are not intimately familiar with Linux kernel development (or, indeed, free software development in general). While there is some technical material here, this is very much a process-oriented discussion which does not require a deep knowledge of kernel programming to understand.

As you begin writing modules for the Linux kernel, you become part of a larger community of developers. Within that community, you can find not only people engaged in similar work, but also a group of highly committed engineers working toward making Linux a better system. These people can be a source of help, ideas, and critical review as welthey will be the first people you will likely turn to when you are looking for testers for a new driver. The central gathering point for Linux kernel developers is the linux-kernel mailing list. All major kernel developers, from Linus Torvalds on down, subscribe to this list. Please note that the list is not for the faint of heart: traffic as of this writing can run up to 200 messages per day or more. Nonetheless, following this list is essential for those who are interested in kernel development; it also can be a top-quality resource for those in need of kernel development help.

Red Hat is the largest Open Source company in the world. It believes that the free discourse of ideas holds the greatest potential for business and human development. Red Hat introduced its comprehensive Package Based distribution of Linux and Linux resources in 1994. Since then, Red Hat Linux has grown to be the most popular and widely used Linux distribution. Red Hat Linux and the Apache Web server are especially popular with Internet Service Providers and for other network resources and roles.

The current Red Hat distribution includes installation and configuration software, the latest version of the Linux kernel, and common utilities and applications. The Red Hat distribution adds tremendous value to the base Linux components and offers good technical support. Also, because of the large install base of Red Hat Linux systems around the world, Red Hat acts as a standardizing force in the diverse Linux community. The Red Hat Linux package is available on CD-ROM, and comes with a free copy of the Red Hat Installation Guide. Although Red Hat distributes the same software free via FTP from mirror sites around the globe, the download is extremely time consuming, so most people elect to purchase the CD-ROM.

Recently, there has been a focus on making Linux more functional for non-technical users. This has been accomplished with desktop environment efforts for GNOME and KDE, two easy-to-configure graphical environments available in Linux. These projects make the Linux desktop more accessible, allowing someone who has little experience outside of the Microsoft Windows setting to be comfortable in the Linux environment.
In the next lesson, the prerequisites will be discussed.