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<H1></H1>



<UL>

	<LI><A HREF="#Heading1">- 1 -</A>

	<UL>

		<LI><A HREF="#Heading2">Introduction to Linux</A>

		<UL>

			<LI><A HREF="#Heading3">Welcome to Linux</A>

			<LI><A HREF="#Heading4">About This Book</A>

			<LI><A HREF="#Heading5">What This Book Is Not</A>

			<LI><A HREF="#Heading6">What Is Linux?</A>

			<UL>

				<LI><A HREF="#Heading7">How to Pronounce Linux</A>

				<LI><A HREF="#Heading8">Linux Versus UNIX</A>

			</UL>

			<LI><A HREF="#Heading9">What Do I Get with a Linux System?</A>

			<LI><A HREF="#Heading10">NOTE</A>

			<LI><A HREF="#Heading11">The Downside of Linux</A>

			<LI><A HREF="#Heading12">About Linuxs Copyright</A>

			<LI><A HREF="#Heading13">NOTE</A>

			<LI><A HREF="#Heading14">CAUTION</A>

			<LI><A HREF="#Heading15">Hardware Requirements</A>

			<LI><A HREF="#Heading16">TIP</A>

			<LI><A HREF="#Heading17">NOTE</A>

			<LI><A HREF="#Heading18">NOTE</A>

			<UL>

				<LI><A HREF="#Heading19">Disk Space Requirements</A>

			</UL>

			<LI><A HREF="#Heading20">CAUTION</A>

			<UL>

				<LI><A HREF="#Heading21">Other Hardware Requirements</A>

				<LI><A HREF="#Heading22">Special Requirements for X Window Systems</A>

			</UL>

			<LI><A HREF="#Heading23">NOTE</A>

			<LI><A HREF="#Heading24">Before You Get Started</A>

			<LI><A HREF="#Heading25">TIP</A>

			<LI><A HREF="#Heading26">The CD-ROM</A>

			<LI><A HREF="#Heading27">NOTE</A>

			<LI><A HREF="#Heading28">TIP</A>

			<LI><A HREF="#Heading29">NOTE</A>

			<LI><A HREF="#Heading30">Summary</A>

		</UL>

	</UL>

</UL>



<P>

<HR SIZE="4">



<H2 ALIGN="CENTER"><A NAME="Heading1<FONT COLOR="#000077">- 1 -</FONT></H2>

<H2 ALIGN="CENTER"><A NAME="Heading2<FONT COLOR="#000077">Introduction to Linux</FONT></H2>

<P><I>by Kamran Husain</I></P>



<P>IN THIS CHAPTER</P>



<UL>

	<LI>Welcome to Linux 

	<P>

	<LI>About This Book

	<P>

	<LI>What This Book Is Not

	<P>

	<LI>What Is Linux? 

	<P>

	<LI>What Do I Get with a Linux System? 

	<P>

	<LI>The Downside of Linux 

	<P>

	<LI>About Linux's Copyright 

	<P>

	<LI>Hardware Requirements 

	<P>

	<LI>Before You Get Started 

	<P>

	<LI>The CD-ROM 

</UL>



<H3 ALIGN="CENTER"><A NAME="Heading3<FONT COLOR="#000077">Welcome to Linux</FONT></H3>

<P>This book is about Linux, a clone of the UNIX operating system that runs on Intel

80x86-based machines, where x is 3 or higher.</P>

<P>You'll find a CD-ROM at the back of the book that contains the Slackware 96 release

of the Linux operating system. With this CD-ROM and this book, you should, I hope,

be up and running with a UNIX-like operating system in a few hours.</P>

<P>Linux is also very portable and flexible because it has now been ported to DEC

Alpha, PowerPC, and even Macintosh machines. Some of these ports are not complete

as this book goes to print, but progress is being made daily by Linux enthusiasts

all over the world to make this free operating system available to all the popular

computing machines in use today. Because the source code for the entire Linux operating

system is freely available, developers can spend time actually porting the code instead

of wondering about whom to pay hefty licensing fees.</P>

<P>Documentation for the many parts of Linux is not very far away either. The Linux

Documentation Project (LDP) is an effort put together by many dedicated and very

smart individuals to provide up-to-date, technically valuable information. All of

this LDP information can be found on the Internet at various Linux source repositories.

Snapshots of the LDP and other Linux documentation files are also provided on the

CD-ROM at the back of this book. Each &quot;HOWTO&quot; document for Linux is the

result of effort from many Linux enthusiasts. The original authors of these documents

are usually also the core Linux developers who have put in hours of time and effort

while struggling with new features of Linux.</P>

<P>These individuals are the ones who deserve the credit and glory for the success

of Linux as a viable, powerful operating system. This is the URL for the Linux Documentation

Project:<FONT COLOR="#0066FF"></FONT>

<PRE><FONT COLOR="#0066FF">http://sunsite.unc.edu/mdw/linux.html

</FONT></PRE>

<H3 ALIGN="CENTER"><A NAME="Heading4<FONT COLOR="#000077">About This Book</FONT></H3>

<P>This first chapter will simply acquaint you with some of the features of Linux.

This chapter doesn't go into a large amount of detail or cover any advanced topics.

Instead, it is intended to give you, a new Linux user, an introduction to what Linux

is about, the features you can expect from it, and the sources of information that

are available.</P>

<P>Don't be afraid to experiment. The system won't bite you. You can't destroy anything

by working on the system. Linux has some amount of security built in to prevent &quot;normal&quot;

users (the role you will now assume) from damaging files that are essential to the

system.</P>

<P>The worst thing that can happen is that you'll delete all of your files, and you'll

have to go back and reinstall the system. So, at this point, you have nothing to

lose--except, maybe, your time, which might be very important to you.</P>

<P>One note of caution when reading this chapter: At times I delve into topics that

might seem very alien to you, especially if you are new to UNIX and Linux. Don't

despair. As we go through this book, you will become more and more familiar with

the topics introduced here. Linux is not an easy system to pick up in one day, so

don't try to do it. There is no substitute for experience; relax and learn Linux

at your own pace.

<H3 ALIGN="CENTER"><A NAME="Heading5<FONT COLOR="#000077">What This Book Is

Not</FONT></H3>

<P>This book makes several assumptions about you, the reader. I hope that we can

safely assume that you have some working knowledge of PCs and Microsoft's Disk Operating

System (MS-DOS). (In some Linux documentation, MS-DOS is also referred to as messy-dos,

but I'll let you be the judge of that!) If you are not familiar with DOS or computers

in general, now would be a good time to pick up a book for beginning with PCs. Still,

you should be able to follow this book without needing any extra material.</P>

<P>Most readers of this book will probably be experienced UNIX users. Unfortunately,

in the case of readers who are not familiar with UNIX, the ordering of chapters in

this book might seem awkward. If you are new to UNIX, refer to the list of other

reference books from Sams Publishing, found in Appendix A, &quot;FTP Sites and Newsgroups.&quot;

We will attempt to cover some of the basics of working with Linux as a user in Part

II of this book, &quot;Using Linux.&quot; Whatever small amount is left over you

can get from these reference books, and from slugging it out with Linux.</P>

<P>One last item before we begin. Even though this book attempts to cover a lot of

topics about Linux, we cannot guarantee that it will cover precisely all the topics

you are looking for. This book will, however, give you an idea of where to look next,

and it will provide you with a good starting point. After a little hand holding,

you should be able to work with Linux on your own. Enough said.</P>

<P>Now, let's get started with Linux.

<H3 ALIGN="CENTER"><A NAME="Heading6<FONT COLOR="#000077">What Is Linux?</FONT></H3>

<P>Linux is a free UNIX clone that supports a wide range of software such as <TT>TeX</TT>,

X Window Systems, the GNU C/C++ compiler, and TCP/IP. It's a versatile, very UNIX-like

implementation of UNIX, freely distributed by the terms of the GNU General Public

License. (See Appendix E, &quot;Copyright Information.&quot;) Linux is also very

closely compliant with the POSIX.1 standard, so porting applications between Linux

and UNIX systems is a snap.</P>

<P>New users of UNIX and Linux might be a bit intimidated by the size and apparent

complexity of the system before them. Many good books on using UNIX and Linux are

available, for all levels of expertise ranging from novice to expert.</P>

<P>Although 95 percent of using Linux is exactly like using other UNIX systems, the

most straightforward way to get going on your new system is with a book tailored

for Linux. This book will get you started. We could list the 5 percent of differences,

but as it's stated in most of my textbooks (which bail out of a hard answer with

a similar phrase): &quot;This is so d--n obvious that we have left it as an exercise

for the reader.&quot;

<H4 ALIGN="CENTER"><A NAME="Heading7<FONT COLOR="#000077">How to Pronounce

Linux</FONT></H4>

<P>Pronouncing the word Linux is one of the great mysteries of the Linux world. Americans

pronounce the name Linux with a long i sound, as in style. Try LIE-nucks. However,

because Linux was originally based on a small PC-based implementation of UNIX called

Minix (pronounced with a short i), the actual pronunciation of Linux preserves this

characteristic: it's LIH-nucks or sometimes even LEEH-nicks.

<H4 ALIGN="CENTER"><A NAME="Heading8<FONT COLOR="#000077">Linux Versus UNIX</FONT></H4>

<P>Linux is not a trademark and has no connection to the trademark UNIX. UNIX is

a trademark of whomever owned it last.</P>

<P>UNIX is one of the most popular operating systems worldwide because of its large

support base and distribution. It was originally developed as a multitasking system

for minicomputers and mainframes in the mid-1970s, but it has since grown to become

one of the most widely used operating systems anywhere, despite its sometimes confusing

interface and lack of central standardization.</P>

<P>UNIX is a multitasking, multiuser operating system. This means that many people

can be using one computer at the same time, running many different applications.

(This differs from MS-DOS, in which only one person can use the system at a time.)</P>

<P>Under UNIX, for users to identify themselves to the system, they must log in.

Logging in entails two steps: entering your login name (the name by which the system

identifies you) and entering your password, which is your secret key to logging into

your account. Because only you know your password, no one else can log into the system

under your user name.</P>

<P>In addition, each UNIX system has a host name assigned to it. It is this host

name that gives your machine a name, and gives it character, class, and charm. The

host name is used to identify individual machines on a network, but even if your

machine isn't networked, it should have a host name. In Chapter 43, &quot;Networking,&quot;

we'll cover setting your system's host name.</P>

<P>Versions of UNIX exist for many systems, ranging from personal computers to supercomputers.

Most versions of UNIX for personal computers are quite expensive and cumbersome.

So where does Linux fit in? Well, Linux is free (which solves the expensive part).

Linux is free because the programmers who put the code together did so from scratch

and did not impose any requirements for payments. With a true altruistic spirit,

they put their code in the shareware, public, or GNU's copyleft domains. The authors

can get paid for it, and do retain authorship, but they let you use their product

without cost. It is also very powerful, and it's easy to install and maintain by

an individual (so much for the cumbersome part).

<H3 ALIGN="CENTER"><A NAME="Heading9<FONT COLOR="#000077">What Do I Get with

a Linux System?</FONT></H3>

<P>Linux is a freely available and distributable look-alike of UNIX developed primarily

by Linus Torvalds at the University of Helsinki in Finland. Linux was further developed

with the help of many UNIX programmers and wizards across the Internet, giving the

ability to develop and change the system to anyone with enough know-how and gumption

to hack a custom UNIX kernel.</P>