This document provides an introduction to Linux, including: - Linux is an open-source UNIX clone that can run on 32-bit and 64-bit hardware and take advantage of multiple processors. - It was created in 1991 by Linus Torvalds as a free implementation of UNIX. - The Linux kernel is maintained by Linus Torvalds and hundreds of developers using a version numbering scheme of major.minor.patchlevel. - Linux has advantages over other operating systems for servers, developers, and desktop users due to its performance, price, stability and large community support.

1. Introduction
to
Linux
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2. Introduction to Linux
 What is Linux, and Who Created it?
 GNU and the GPL
 Unix/GNU, What is the Difference?
 POSIX Compliance
 Other POSIX Operating Systems
 Uses of Linux
 Advantages and Disadvantages
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3. What is Linux
 Linux is a UNIX clone
 It can run on 32 bit and 64 bit hardware
 Linux is a true multitasking environment
 Fully capable of taking advantage of multiple processors
 Can address up to 64 GB of RAM
 Partial POSIX Compliance
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4. History
 The history of Linux began with Unix in 1969
› Unix was created at Bell Labs with the goals:
 Simplicity
 Recycleable code
 Written in C as opposed to assembly
 Development started in 1991
› Linus Torvalds wanted to create a free implementation of
UNIX
› By 1993 there were 12000 Linux users
› Today Linux rivals UNIX in stability and scalability
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5. The Linux Kernel
 The Linux kernel is currently maintained by Linus Torvalds and
a few hundred other developers
 Releases are numbered in a very ordered fashion.
› Major.minor.patchlevel
› Odd minor numbers are development kernels
› Thus
 2.4.20 latest stable kernel
 2.5.67 latest development kernel
 Will become the 2.6 kernel
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6. Design
 The Linux kernel has a monolithic design
 The other approach is the microkernel design
 Both have their upsides and downsides
› Monolithic kernels
 Easier to build and design
 Generally faster
 More recompiles
 Less object oriented
› Micro kernels
 Considered safer
 Easier to develop drivers for
 Only recompile for upgrades
 Generally slower
 Much harder to build and design
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7. So Why Should I Use Linux?
 As a server platform
› few other operating systems can match Linux in:
 Performance
 Price
 Stability
 For Developers
› Resources:
 Linux has a tremendous number of tools available for developers. And
they are all free.
 For the Desktop
› It's fun
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8. Advantages
 Linux is free
› Can't say that enough
› It's great for poor college students
 Learning Linux means learning UNIX, and UNIX is the largest
server platform in the world
 Community
› The Linux community is very active and helpful
› This makes support very rapid
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9. But it's hard to learn
 Linux is much harder than Windows
 It's harder to use than Windows
 It lacks all those great automated installation tools
 You have to manually configure hardware
 There is lots of hardware out there that just won't run in Linux
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10. Some Linux Basics
 File System
› Linux is much more hierarcal than Windows
 Everything starts at the root
 /
 Boot -- contains the kernel and system map
 Bin -- contains the basic system binaries
 Dev -- all the device entries
 Etc -- can't think of any other place to put it
 Home -- where all the users live
 Lib -- system libraries
 Mnt -- place to mount filesystems
 Proc -- system information
 Root -- the root user's home
 Sbin -- system binaries
 Usr -- where user accessible programs go
 Var -- logs and such
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11. THANK YOU
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