# Preface

This is a book about Linux, a freely available clone of the Unix operating system for personal computers. Linux was first developed by Linus Torvalds, who built the first Linux kernel and continues to centrally coordinate improvements. The operating system continues to grow under the dedicated cultivation of a host of other programmers and hackers all over the world, all connected through the Internet. Beyond the kernel code, Linux includes utilities and commands from the Free Software Foundation's GNU project, Berkeley Unix (BSD), and a complete port of the X Window System (XFree86) from the X Consortium, in addition to many features written specifically for Linux. Even more recent projects extend Linux in exciting ways, some through changes to the kernel -- such as real-time scheduling and RAID support -- and some through libraries and applications that radically change the user's experience; the GNOME and KDE desktops briefly covered in this book are the most prominent examples.

This book is a quick reference for the basic commands and features of the Linux operating system. As with other books in O'Reilly's "In a Nutshell" series, this book is geared toward users who know what they want to do and have some idea how to do it, but just can't remember the correct command or option. We hope this guide will become an invaluable desktop reference for the Linux user.

## 0.1. Other Resources

This book will not tell you how to install and maintain a Linux system. For that, you will probably want O'Reilly's Learning Red Hat Linux or Learning Debian GNU/Linux, by Bill McCarty, which contain Linux distributions on CD-ROM and provide help with installation and configuration. Alternatively, Running Linux by Matt Welsh, Matthias Kalle Dalheimer, and Lar Kaufman is an in-depth guide suitable for all major distributions. For networking information, check out Linux Network Administrator's Guide by Olaf Kirch and Terry Dawson. In addition to O'Reilly's Linux titles, our wide range of Unix, X, Perl, and Java titles may also be of interest to the Linux user.

### 0.1.1. Online Documentation

The Internet is also full of information about Linux. One of the best resources is the Linux Documentation Project at http://www.linuxdoc.org.It has numerous short guides called HOWTOs, along with some full manuals. For online information about the GNU utilities covered in this book, consult http://www.gnu.org(or one of the dozens of mirror sites around the world). The Free Software Foundation, which is in charge of GNU, publishes its documentation in a number of hard-copy books about various tools.

### 0.1.2. Linux Journal and Linux Magazine

Linux Journal and Linux Magazine are monthly magazines for the Linux community, written and published by a number of Linux activists. They contain articles ranging from novice questions and answers to kernel programming internals. Linux Journal is the oldest magazine and is published by S.S.C. Incorporated, http://www.ssc.com.Linux Magazine is at http://www.linuxmagazine.com.

### 0.1.3. LinuxUsenet Newsgroups

If you have access to Usenet news, the following Linux-related newsgroups are available:

comp.os.linux.announce

  A moderated newsgroup containing announcements of new software, distributions, bug reports, and goings-on in the Linux community. All Linux users should read this group. Submissions may be mailed to linux-announce@news.ornl.gov.

comp.os.linux.help

  General questions and answers about installing or using Linux.

comp.os.linux.admin

  Discussions relating to systems administration under Linux.

comp.os.linux.networking

  Discussions relating to networking with Linux.

comp.os.linux.development

  Discussions about developing the Linux kernel and system itself.

comp.os.linux.misc

  A catch-all newsgroup for miscellaneous discussions that don't fall under the previous categories.

There are also several newsgroups devoted to Linux in languages other than English, such as fr.comp.os.linux in French and de.comp.os.linux in German.

### 0.1.4. Online Linux Support

There are many ways of obtaining help online, where volunteers from around the world offer expertise and services to assist users with questions and problems.

The OpenProjects IRC Network is an IRC network devoted entirely to Open Projects -- Open Source and Open Hardware alike. Some of its channels are designed to provide online Linux support services. IRC stands for Internet Relay Chat, and is a network service that allows you to talk interactively on the Internet to other users. IRC networks support multiple channels on which groups of people talk. Whatever you type in a channel is seen by all other users of that channel.

There are a number of active channels on the OpenProjects IRC network where you will find users 24 hours a day, 7 days a week who are willing and able to help you solve any Linux problems you may have, or just chat. You can use this service by installing an IRC client like irc-II, connecting to servername >irc.openprojects.org:6667>, and joining the `#linpeople` channel.

### 0.1.5. Linux User Groups

Many Linux User Groups around the world offer direct support to users. Many Linux User Groups engage in activities such as installation days, talks and seminars, demonstration nights, and other completely social events. Linux User Groups are a great way of meeting other Linux users in your area. There are a number of published lists of Linux User Groups. Some of the better-known ones are:

Groups of Linux Users Everywhere

  http://www.ssc.com/glue/groups

LUGlist project

  http://www.nllgg.nl/lugww

LUGregistry

  http://www.linux.org/users

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