Glossary of terms</> <glossentry id=unix> <glossterm>UNiplexed Information and Computing System</> <acronym>Unix, UNICS</> <glossdef> <para> Speaking of the name Unix, it was intended as a pun on an earlier system called "Multics" (Multiplexed Information and Computing Service). </> <para> In earlier versions of this document, I used to say that Unix was a common name for a group of superior operating systems which shared most of the key design ideas. While there was nothing wrong with that statement, I went to search the Internet for some more formal explanations: </> <para> Short introduction on the <ulink url="">UGU</> site says: </para> <blockquote> <para> Unix - /yoo'niks/ Plural "Unices". An interactive time-sharing operating system invented in 1969 by Ken Thompson after Bell Labs left the Multics project, originally so he could play games on his scavenged PDP-7. Dennis Ritchie, the inventor of C, is considered a co-author of the system. </> </> <para> Similar and more detailed description from <ulink url="">searchSolaris</>: </> <blockquote> <para> Unix is an operating system that originated at Bell Labs in 1969 as an interactive time-sharing system. Ken Thompson and Dennis Ritchie are considered the inventors of Unix. The name (pronounced YEW-nihks) was a pun based on an earlier system, Multics. In 1974, Unix became the first operating system written in the C language. Unix has evolved as a kind of large freeware product, with many extensions and new ideas provided in a variety of versions of Unix by different companies, universities, and individuals. </> <para> Partly because it was not a proprietary operating system owned by any one of the leading computer companies and partly because it is written in a standard language and embraced many popular ideas, Unix became the first open or standard operating system that could be improved or enhanced by anyone. A composite of the C language and shell (user command) interfaces from different versions of Unix were standardized under the auspices of the IEEE as the Portable Operating System Interface (POSIX ). In turn, the POSIX interfaces were specified in the X/Open Programming Guide 4.2 (also known as the "Single Unix Specification" and "Unix 95"). Version 2 of the Single Unix Specification is also known as Unix 98. The "official" trademarked Unix is now owned by the The Open Group, an industry standards organization, which certifies and brands Unix implementations. </> </blockquote> </glossdef> </glossentry> <glossentry id="gnulinux"> <glossterm>Free Software, GNU and Linux</> <glossdef> <para> <mediaobject> <imageobject> <imagedata fileref="images/rmstallman.jpg"> </> <imageobject> <imagedata fileref="images/rmstallman.eps"> </> <imageobject> <imagedata fileref="images/rmstallman.gif"> </> </> Richard Stallman, a MIT hacker, started an initiative to create a completely free operating system (free as in <emphasis /freedom/). Among other things, his decision was based on frustrations and problems he saw in non-disclosure agreements. They once prevented his colleague from giving him the source code for a laser printer driver (Stallman wanted to include automatic paper-jam notification features). </> <para> Highly motivated to do The Right Thing (tm), he later quit the job at MIT (so they couldn't possibly claim copyright on his work) and, in 1984, started the <ulink url="">GNU</> ("Gnu's Not Unix") project, whose goal was to protect freedom and supply users with full-featured free software packages for their computers. GNU is a wonderful philosophy that could surely affect non computer-related areas as well. </> <para> You can see the <ulink url="">original Stallman's announcement</> from Sep 27, 1983 / 10:35:59 PST in the excellent <ulink url="">Google Groups</> archive! </> <para> GNU developers have re-written all the necessary Unix system tools and utilities, released them as Free Software (under the GNU GPL licence), and they only needed a kernel to accomplish the initial goal. </> <para> Independently, in 1991, Linus Torvalds (from the Helsinki University) announced his first public release of the kernel he was working on - Linux. He was a student back then, and wanted to create a cheap alternative to high-priced Unix systems, which would run on PC (i386) compatible machines. Combining the Linux kernel and the GNU tools, the free GNU/Linux system became a reality. Linus wrote the kernel from scratch ("from zero") and it was one of the first free Unix-like variants which, supported by the great GNU community and their software, got the Free Software movement really going (from the general-public perspective, not technically, of course). </> <para> All the way back in 1994, Peter van der Linden wrote the following in his excellent book, titled “Expert C Programming; Deep C Secrets” (ISBN 0-13-177429-8): </para> <blockquote> <para> The Free Software Foundation is a unique organization founded by ace MIT hacker Richard Stallman. By the way, we use “hacker” in the old benevolent sense of “gifted programmer”; the term has been debased by the media, so outsiders use it to mean “evil genius”. Like the adjective <emphasis>bad</>, “hacker” how has two opposing meanings, and you have to figure it our from the context. </> <para> Stallman's Free Software foundation was founded on the philosophy that software should be free and freely available to all. FSF's charter is “to eliminate restrictions on copying, redistribution, understanding and modification of computer programs” and their ambition is to create a public-domain implementation of Unix called GNU (it stands for “GNU's Not Unix”. Yes, really). </> <para> Many computer science graduate students and others agree with the GNU philosophy, and have worked on software products that FSF packages and distributes for free. This pool of skilled labor donating their talent has resulted in some good software. One of the FSF's best products is the GNU C compiler family. gcc is a robust, agressive optimizing compiler, available for many hardware platforms and sometimes better than the manufacturer's compiler. </> </blockquote> <para> However, there were other efforts, such as those by the BSD people who still had problems with the licensing issues and copyrights, but they have rewritten all the parts in question and released free BSD variants: <ulink url="">FreeBSD</>, <ulink url="">NetBSD</> and <ulink url="">OpenBSD</>. </> <para> <!-- <note><title>Please Note: Linux (and other free operating systems today) have picked up the best from the Unix world and additionally, they have many end-user advantages over the orthodox Unix machines (primarily in aspects of "user friendlyness" and GUI environments). --> Open Source OSS, OSI Open Source is a somewhat newer term which was generally accepted to help promote Free Software in commercial environments. It relies only on practical benefits of open source code (quality, reliability, cost of maintenance) and has no greater philosophy behind it. More information can be found at the Open Source Initiative website. It is therefore important to know the disctinction between the two. Important! Read more about the Free Software, Open Source and the correct interpretation of the word free on the Debian's What Does Free Mean? page. It is interesting to mention that Linux is a monolithic kernel and shares many ideas with its Unix counterparts. However, the GNU people have a different vision of how kernels should look like and they are working on The Hurd microkernel. Debian GNU/Hurd port is in progress, and you can see the current status or download the software from the Debian GNU/Hurd port page. Monolithic and microkernels are fundamentally different, and there's been much of debate if microkernels would ever prove useful in real-life application. Linus Torvalds, for example, is constantly bashing microkernel operating systems ("just say NO to drugs, and maybe you won't end up like The Hurd people"). Alan Cox, the former maintainer Linux production tree kernel maintainer, who has more sympathies for The Hurd, once said that The Hurd was more about Richard Stallman's idea about how a system should work to promote community than about high perfomance OS design. Technically, The Hurd and microkernels in general do offer many advantages over the traditional Unix kernels; those interested in getting more information should see hurd-paper.html and hurd-talk.html (for The Hurd), or the QNX website (for the proprietary, mature, microkernel-based Unix). Let's quote something from the official &LNK6; page:
Debian was begun in August 1993 by Ian Murdock, as a new distribution which would be made openly, in the spirit of Linux and GNU. Debian was meant to be carefully and conscientiously put together, and to be maintained and supported with similar care. It started as a small, tightly-knit group of Free Software hackers, and gradually grew to become a large, well-organized community of developers and users. Since many people have asked, Debian is pronounced 'deb ee n'. It comes from the names of the creator of Debian, Ian Murdock, and his wife, Debra. Debian is produced by nearly one thousand developers spread around the world who volunteer in their spare time. Few of the developers have actually met in person. Communication is done primarily through e-mail (mailing lists at and IRC (#debian channel at The Debian Project is an association of individuals who have made common cause to create a free operating system. This operating system that we have created is called Debian GNU/Linux, or simply Debian for short. An operating system is the set of basic programs and utilities that make your computer run. At the core of an operating system is the kernel. The kernel is the most fundamental program on the computer and does all the basic housekeeping and lets you start other programs. Debian systems currently use the Linux kernel. Linux is a completely free piece of software started by Linus Torvalds and supported by thousands of programmers worldwide. However, work is in progress to provide Debian for other kernels, primarily for the Hurd. The Hurd is a collection of servers that run on top of a microkernel (such as Mach) to implement different features. The Hurd is free software produced by the GNU project. A large part of the basic tools that fill out the operating system come from the GNU project; hence the names: GNU/Linux and GNU/Hurd. These tools are also free. Of course, the thing that people want is application software: programs to help them get what they want to do done, from editing documents to running a business to playing games to writing more software. Debian comes with over 8710 packages (precompiled software that is bundled up in a nice format for easy installation on your machine) - all of it free. It's a bit like a tower. At the base is the kernel. On top of that are all the basic tools. Next is all the software that you run on the computer. At the top of the tower is Debian - carefully organizing and fitting everything so it all works together. You may be wondering: why would people spend hours of their own time to write software, carefully package it, and then give it all away? The answers are as varied as the people who contribute. Some people like to help others. Many write programs to learn more about computers. More and more people are looking for ways to avoid the inflated price of software. A growing crowd contribute as a thank you for all the great free software they've received from others. Many in academia create free software to help get the results of their research into wider use. Businesses help maintain free software so they can have a say in how it develops - there's no quicker way to get a new feature than to implement it yourself! Of course, a lot of us just find it great fun. Debian is so committed to free software that we thought it would be useful if that commitment was formalized in a written document. Thus, our &LNK7; was born.