Learn Unix through a series of 24 one-hour lessons that teach you the essentials of Unix from the ground up.

Dave Taylor is the founder of Growing Ventures, Inc., a consultancy that matches professional service providers with startups. He the creator of The Internet Mall and iTrack.com, and helps startups with strategies and tactics. Dave is also the creator of the Elm mail system for Unix; he contributed to the development of BSD 4.4, and has published various books, including the third edition of Sams Teach Yourself Unix in 24 Hours.

Introduction Introduction Welcome to the fourth edition ofSamsTeach Yourself Unix in 24 Hours! This book has been designed to be helpful as a guide as well as a tutorial for both beginning users and those with previous Unix experience. The reader of this book is assumed to be intelligent, but no familiarity with Unix is expected or required. Does Each Chapter Take an Hour? You can learn the concepts in each of the 24 lessons in one hour. If you want to experiment with what you learn in each lesson, you might take longer than an hour. However, all the concepts presented here are straightforward. If you are familiar with Windows applications or the Macintosh, you will be able to progress more quickly through the lessons. What If I Take Longer Than 24 Hours? Since the publication of the first edition of this book, I've received a considerable amount of praise and positive feedback, but the one message that has always been a surprise is "I finished your book, but it took me a lot longer than 24 hours." Now you can read here, direct from the author: It's okay! Take your time and make sure you try everything as you go along. Learning and remembering is more important than speed. And if you do finish it all in 24 hours, let me know! Are There Really 24 Hours Worth of Lessons? Actually, don't tell the publisher, but if you look at Appendix B, on working with the Apache Web Server in the Unix environment, you'll find out a secret: there are actually 25 hours worth of lessons in this book. I'll make you a deal: you don't tell anyone at Sams, and I won't either. How to Use This Book This book is designed to teach you topics in one-hour lessons. All the books in theSams Teach Yourselfseries enable you to start working and become productive with the product as quickly as possible. This book will do that for you! Each hour, or lesson, starts with an overview of the topic to inform you of what to expect in that lesson. The overview helps you determine the nature of the lesson and whether the lesson is relevant to your needs. Main Section Each lesson has a main section that discusses the lesson topic in a clear, concise manner by breaking the topic down into logical components and explaining each component clearly. Interspersed in each lesson are special elements, called Tips, Notes, and Cautions, to provide additional information. Note -Notes are designed to clarify the concept that is being discussed. They elaborate on the subject, and if you are comfortable with your understanding of the subject, you can bypass them without danger. Tip -Tips inform you of tricks or elements that are easily missed by most computer users. You can skip them, but often Tips show you an easier way to do a task. Caution -A Caution deserves at least as much attention as a Tip because Cautions point out a problematic element of the topic being discussed. Ignoring the information contained in the Caution could have adverse effects on the task at hand. These are the most important special elements in this book. Tasks This book offers another special element called a Task. These step-by-step exercises are designed to walk you quickly through the most important skills you can learn in Unix. Each Task has three parts: Description, Action, and Summary. Workshops The Workshop section at the end of each lesson provides Key Terms and Exercises that reinforce concepts you learned in the lesson and help you apply them in new situations. You can skip this section, but we recommend that you go through the exercises to see how the concepts can be applied to other common tasks. The Key Terms al