Christine Bresnahan - Linux Essentials

Second Edition

Christine Bresnahan

Richard Blum

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Copyright 2015 by John Wiley & Sons, Inc., Indianapolis, Indiana
Published simultaneously in Canada
ISBN: 978-1-119-09206-3
ISBN: 978-1-119-09219-3 (ebk.)
ISBN: 978-1-119-09214-8 (ebk.)

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To those looking to further their knowledge of Linux.
Let the journey begin!

A wise man is full of strength, and a man of knowledge
enhances his might Prov 24:5 (ESV)

First, all glory and praise go to God, who through His Son, Jesus Christ, makes all things possible and gives us the gift of eternal life.

Many thanks go to the fantastic team at Sybex for their outstanding work on this project. Thanks to acquisitions editor Kenyon Brown for offering us the opportunity to work on this book. Also thanks to developmental editor Gary Schwartz for keeping things on track and making this book more presentable. Thanks, Gary, for all your hard work and diligence. Technical editor Kevin E. Ryan did a wonderful job of double-checking all of the work in the book, in addition to making suggestions to improve the content. Thanks also goes to the young and talented Daniel Anez (theanez.com) for his illustration and cover image work. We would also like to thank Carole Jelen at Waterside Productions for arranging this opportunity for us and for helping us in our writing careers.

Christine would particularly like to thank her husband, Timothy, for his encouragement, patience, and willingness to listen, even when he has no idea what she is talking about.

Rich would like to thank his wife, Barbara, for her love and support of his late-night writing habit, and thank Christine and Timothy for their continued friendship all these years.

Christine Bresnahan, CompTIA Linux+, LPIC-1, Linux Essentials, started working with computers more than 30 years ago in the IT industry as a systems administrator. Christine is an adjunct professor at Ivy Tech Community College, where she teaches Linux certification and Python programming classes. She also writes books and produces instructional resources for the classroom.

Richard Blum, CompTIA Linux+, LPIC-1, Linux Essentials, has worked in the IT industry for more than 25 years as both a systems and network administrator, and he has published numerous Linux and open source books. Rich is an online instructor for Linux and web programming courses that are used by colleges and universities across the United States. When he is not being a computer nerd, Rich enjoys spending time with his wife, Barbara, and his two daughters, Katie Jane and Jessica.

This book you hold in your hands provides a solid introduction to the Linux operating system. As its title suggests, it will give you the essential knowledge to begin using and managing this powerful operating system (OS), which is an important one in todays computing world.

The following pages explain why you should care about Linux, describe the purpose of the Linux Professional Institutes Linux Essentials certification, offer advice on who should buy this book, detail how the book is organized, and explain some of the typographical and organizational elements within the books chapters.

Linux is a clone of the Unix OS, which has been popular in academic and business environments for years. Linux consists of a kernel, which is the core control software, and many libraries and utilities that rely on the kernel to provide features with which users interact. The OS is available in many distributions, which are collections of a specific kernel with specific support programs. Popular Linux distributions include Arch, CentOS, Debian, Fedora, Gentoo, Mandriva, openSUSE, Red Hat, Slackware, SUSE Enterprise, and Ubuntu, but there are hundredsif not thousandsof other Linux distributions. This book focuses on tools and techniques that are used in most, if not all, distributions, although from time to time it demonstrates some distribution-specific tools.