This document provides an overview of Linux history and features. It discusses that Unix was developed in 1969 at Bell Labs and led to various variants. Linux was developed in 1991 by Linus Torvalds as an open source clone of Unix. It discusses some popular Linux distributions like Red Hat, Ubuntu, Debian etc. It then covers basic Linux commands, text editors like Vi and Emacs, available software packages, user management and how to setup a basic web server. It encourages computer engineers to learn Linux as most professional applications and tools are available on Linux platforms.

1. Linux History & Features

2. Roadmap
 What is Unix?
 What is Linux?
 Which Linux Distribution is better?
 Linux : Advantages & Disadvantages
 Basic Commands
 Vi and Emacs
 Available Software
 Web Server

3. What is Unix?
 A multi-task and multi-user Operating System
 Developed in 1969 at AT&T’s Bell Labs by
 Ken Thompson (Unix)
 Dennis Ritchie (C)
 Douglas Mcllroy
 Some other variants: System V, Solaris, SCO
Unix, SunOS, 4.4BSD, FreeBSD, NetBSD,
OpenBSD, BSDI

4. Before Linux: UNIX
 Many difficulties in Multics development
 1969
 AT&T pulled out of Multics
 Ken Thompson
 A simplified version of Multics  UNIX
 Dennis Ritchie
 Rewrite the UNIX in C
 AT&T cannot sell the UNIX
 UNIX is the first free Operating System

5. What is Linux?
 A clone of Unix
 Developed in 25 August 1991 by Linus Torvalds, a
Finish graduate student
 Inspired by and replacement of Minix
 Linus' Minix became Linux
 Consist of
 Linux Kernel
 GNU (GNU is Not Unix) Software
 Software Package management
 Others

6. What is Linux?
 Originally developed for
32-bit x86-based PC
 Ported to other
architectures, eg.
 Alpha, VAX, PowerPC,
IBM S/390, MIPS, IA-64
 PS2, TiVo, cellphones,
watches, Nokia N810,
NDS, routers, NAS, GPS,
…

7. Which Linux Distribution is better?
 > 300 Linux Distributions
 Slackware (one of the oldest, simple and stable distro.)
 Redhat
 RHEL (commercially support)
 Fedora (free)
 CentOS (free RHEL, based in England)
 SuSe ( based in German)
 Gentoo (Source code based)
 Debian (one of the few called GNU/Linux)
 Ubuntu (based in South Africa)
 Knoppix (first LiveCD distro.)
 …

8. Advantages of Linux
 Linux is free:
 Price is zero.
 Unlimited copies permitted.
 Read and change source code.
 Manuals are on-line.
 Common in scientific circles.
 Text interface is good for batch processing
and management.

9. Disadvantages of Linux
 Text interface is not as user-friendly as
Windows.
 But, has StarOffice software which is looks much
like Windows.
 Less commercial software available.
 But, more scientific software available.
 More difficult to set up.
 But, once set up, easy to manage.

10. Basic Commands
 ls  which
 $ ls -l  $ which ls
 $ ls -a  whereis
 $ ls -la  $ whereis ls
 $ ls -l --sort=time  locate
 $ ls -l --sort=size -r  $ locate stdio.h
 cd  $ locate iostream
 $ cd /usr/bin  rpm
 pwd  $ rpm -q bash
 $ pwd  $ rpm -qa
 ~  $ rpm -qa | sort | less
 $ cd ~  find
 ~user  $ find / | grep stdio.h
 $ cd ~VeerBahadur  $ find /usr/include | grep stdio.h

11. Vi
 2 modes  Delete
 Input mode
 dd (delete a line)
 d10d (delete 10 lines)
 ESC to back to cmd mode  d$ (delete till end of line)
 Command mode  dG (delete till end of file)
 Cursor movement
 x (current char.)
 h (left), j (down), k (up), l (right)
 Paste
 ^f (page down)
 p (paste after)
 ^b (page up)
 P (paste before)
 ^ (first char.)  Undo
 $ (last char.)  u
 G (bottom page)  Search
 :1 (goto first line)  /
 Swtch to input mode  Save/Quit
 a (append)  :w (write)
 i (insert)  :q (quit)
 o (insert line after  :wq (write and quit)
 O (insert line before)  :q! (give up changes)

12. Emacs
 $ emacs  Paste
 Cursor movement  ^y (yank)
 ^f (forward one char.)  Undo
 ^b (backward one char.)  ^/
 ^a (begin of line)  Load file
 ^e (end of line)  ^x^f
 ^n (next line)  Cancel
 ^p (prev. line)  ^g
 ^v (page up)  Save/Quit
 alt-v (page down)  ^x^c (quit wiout saving)
 Deletion  ^x^s (save)
 ^d (delete one char)  ^x^w (write to a new file)
 alt-d (delete one word)
 ^k (delete line)

13. Available Software
 Compilers:
 G77 (FORTRAN 77)
 Gcc ( C )
 g++ (C++)
 Text editors
 Emacs
 Typesetting
 Troff, TeX
 Graphing
 Gnuplot

14. Available Software
 StarOffice provides a Windows-like
environment:
 Word processor
 Spreadsheet
 Overhead slide designer
 Can load and save existing files created on a
Windows computer.

15. User Management
 Simple way to add user is adduser command
 Passwd will allow to change the passwd
 Ofcourse there are host of GUI tools for all
these user management
 Group all common user to single group
 Be carefull while editing /etc/passwd
 /etc/shadow passwd file may also exist.

16. User Management
 Common files to look at
 /etc/passwd
 /etc/group
 /etc/shadow
 /etc/samba

17. Web server on Linux
 Apache server is mostly available on Linux
 Rpm –q –all | grep apache to check
 This can be started via init services
 /etc/rc.d/init.d/httpd start
 Configuration files are at /etc/httpd/conf/
 Normally log files at /var/log/httpd

18. Lost Root Passwd
 If you have Lilo installed, type
 LILI: linux init 1
 Change the root passwd, reboot aga
 If you have installed grub
 Type ‘e’ to go to edit mode, add init 1
argument at the end
 Boot with knoppix or single floppy linux
 Mount the disk and change root passwd
 Reboot !!

19. GNU/Linux & You (Computer Engineer)
 Ok! ! !
 Windows is more popular
 90% of Desktop computers run Windows
 But!
 The 90% contains children, officers, …
 How many CEs do use the Windows?
 How many professional applications
(supercomputing) do use the Linux?

20. GNU/Linux & CEs
 Linux is NOT for dummies
 Linux is for CEs
 Linux does NOT hide anything
 In details boot message
 Kernel messages
 No registry  All config files are text files
 Using Linux needs computer knowledge
 You have the knowledge

21. GNU/Linux & You
 If you target PhD in Computer Science
 You must learn Linux
 Most tools, simulators, protocols, … are
implemented & tested in Linux
 If you target Engineering in Iran
 Linux Administrator
 Linux Application developer
 Embedded Linux Developer

22. Presented By : Beer Bahadur Singh
Designation : Asst. S/W Engineer(Trainee)
Id No : VGT 153 T