History of linux

A Brief History of Linux

Shiwang Kalkhanda © Copyright 2013http://tosl.wordpress.comCorrections, suggestions, contributions and translations are welcome

Shiwang Kalkhanda([email protected])

The presentation is licensed under Creative Commons Attribution-Share Alike 3.0 license

EVENTS LEADING TO CREATION OF LINUX

● The Unix operating system was conceived and implemented by Dennis, Ritchie, Ken Thompson, Brian W. Kerrington Of Bell Labs in 1969.

● The name UNIX was initially written as UNICS (Uniplex Information and Computing System)

● Anyone could get UNIX from the Bell Labs on a tape For a nominal fee, source code of the OS too had been Provided !!!

● 1970: University of California, Berkeley made further Improvement to UNIX source – included TCP/IP Networking in it. This is known as the BSD (Berkeley Systems Distribution) and initially released in 1977.It became yet another popular flavour of UNIX.

● Source code was publicly made available: the license permitted redistribution, with source Or without source provided that Berkeley was credited.

● Modern versions of BSD: NetBSD, OpenBSD and Mac OS X.

FREE SOFTWARE MOVEMENT

● The tape of the Bell labs produced for its UNIX became the basis for a commercialization of UNIX in 1984. By then AT & T had become a telecommunication giant in the world. Since then UNIX became expensive and a trademark of AT & T. Its product ( AT & T) UNIX …...............!

● No source code made available for folks to play with …...........!

● By the early 1980s proprietary software development (by profit making companies) has been becoming popular.

● Source codes of the software had been kept secret and Hidden (as with DOS, MX Windows XXP, Vixta)

● 1983: comes the Richard Stallman of MIT in Cambridge, USA to initiate a battle against proprietary software.

● This marks the birth of the Free Software Foundation and Subsequently the huge collection of the GNU (Gnu is Not Unix) software.

● Licensing: give everyone the right to copy, distribute, and Modify the work, though under strict terms and conditions.

IMPETUS FOR KERNEL DEVELOPMENT

● Richard Stallman started the GNU project with the goal of creating a free UNIX-like operating system. As part of this work, he wrote the GNU General Public License (GPL) and introduced the concept of copyleft against copyright. By the early 1990s there was almost enough available software to create a full operating system. However, the GNU kernel, called Hurd, failed to attract enough attention from developers leaving GNU incomplete.

● MINIX, a Unix-like system intended for academic use, was released by Andrew S. Tanenbaum in 1987. While source code for the system was available, modification and redistribution were restricted. In addition, MINIX's 16-bit design was not well adapted to the 32-bit features of the increasingly cheap and popular Intel 386 architecture for personal computers. In the early nineties a commercial UNIX operating system for Intel 386 PCs was too expensive for private users.

● These factors and the lack of a widely adopted, free kernel provided the impetus for Torvalds's starting his project. He has stated that if either the GNU or 386BSD kernels were available at the time, he likely would not have written his own

● The Linux OS as we see and use it today is now called The GNU/Linux as it is the huge collection of GNU software Plus the kernel developed by Linus Torvalds and thousands of volunteers around the world which made it possible for Any Linux distribution to exist today.

ABOUT LINUS TORVALDS …... & LINUX DEVELOPMENT

● Born on December 28, 1969 in Helsinki, Finland.Son of Nils and Anna Torvalds. Both parents pursued careers in journalism.

● Linus took an early interest in computers mainly through the influence of his maternal grandfather. Excelled in math in secondary school.

● Linus Torvalds enrolled at the University of Helsinki in 1988 where he studied computer science. After buying a PC with an Intel 386 CPU, he began using Minix, an Unix-inspired operating system created by Andrew Tannenbaum for use as a teaching tool.

● Linus was not impressed with the system in general and in particular he lamented its inability to do terminal emulation, which he needed so he could connect to the university's computers.

● When he was a graduate student, Linus decided to do the terminal emulation program himself, independently of Minix. These were the first steps toward creating Linux.

● Linus quickly developed the terminal emulation program and it was sufficient for his needs for a while. However, Linus began thinking that it would be nice to be able to do other things with it like transferring and saving files. This is where Linux was really born.

A HISTORIC POST ON USENET GROUP

● On 25 August 1991, he announced this system in a Usenet posting to the newsgroup "comp.os.minix."...

LINUX NAMING

● As it is apparent from the posting, Linus himself didn't believe that his creation was going to be big enough to change computing forever. Linux version 0.01 was released by mid September 1991, and was put on the net. Then Linux belonged to the world.

● Linus Torvalds had wanted to call his invention Freax, of "freak", "free", and "x" (as an allusion to Unix). During the start of his work on the system, he stored the files under the name "Freax" for about half of a year. Torvalds had already considered the name "Linux," but initially dismissed it as too egotistical.

● LINUS TORVALDS →

LINUX LICENSE & MASCOT

● Torvalds first published the Linux kernel under its own licence, which had a restriction on commercial activity. In the middle of December 1992 he published version 0.99 using the GNU GPL

● Torvalds announced in 1996 that there would be a mascot for Linux, a penguin. Torvalds mention he was bitten by a Little Penguin on a visit to the National Zoo & Aquarium, Canberra, Australia. Larry Ewing provided the original draft of today's well known mascot based on this description.

● The name Tux was suggested by James Hughes as derivative of Torvalds' UniX.

WHAT IS LINUX …..?

● Linux is a Operating Sytem Kernel , used by Linux family of Unix-like Operating Systems

● The Linux kernel is released under the GNU General Public License version 2 and is developed by contributors worldwide.

● The whole system uses GNU tools: C library, gcc, binutils, fileutils, make, emacs... So the whole system is called “GNU / Linux”

● Many Linux distributions have been released based upon the Linux kernel.

● An operating system using the Linux kernel and including a collection of apps is called LINUX DISTRO or LINUX DISTRIBUTION.

● There are hundreds available .Some of the most popular are Red Hat, Fedora, SUSE, Debian, and Ubuntu

WHAT IS LINUX DISTRO....?

● “Distros” (short for Distributions) are collections of software bundled with the Linux kernel and tuned to play well together.

● Distros exist for special purposes, but even for general purpose desktop use there are dozens, each of which is “perfect” to its creators

Web Tools& Browsers

Word Processing& Office Apps

Networking &ConfigurationTools

Desktop Environment

Multimedia& Games

The “Perfect” Distro

WHAT IS LINUX DISTRO....?

● Some Things That Characterize Distros:

– Graphical-Desktop vs. Server, Firewall, etc.

– Choice of Included Applications

● And what flexibility is there to add more later

– Aimed at “Beginner” vs. “Expert”

● Active Forums Provide On-Line Support

– Level of Hardware Supported

● New vs. Older Computers, Wireless Cards, etc.

– Large-Company Effort(Commercial) vs. Community

There are HUNDREDS of Distros, But Only a Handful That a New User Needs to Consider

DISTRO LANDSCAPE

●

PREMIERE WEBSITE FOR DISTRO INFORMATIONS

● http://www.distrowatch.com

● Detailed Entries For Hundreds of Distros● Write-ups on the Most Popular● A Weekly Newsletter● Search Capability● Tutorials

COMMERCIAL DISTROS

● Red Hat: http://www.redhat.com/

– The most popular. Reliable, safe, user friendly, easy to install,

– supported by all hw and sw vendors.

● Suse (Novell): http://www.suse.com/

– The main alternative. Easy to install, user friendly.

● Mandrake: http://www.mandrakelinux.com/

– User friendly, easy to install, more innovative, but less stable

– (perhaps better since the introduction of community pre­releases).

– More targeted to individual users. Little vendor support.

COMMUNITY DRIVEN DISTROS..

● Debian: http://debian.org/

– Very stable and safe, but more difficult to configure and install.

– Stable releases not frequent enough (every 2 or 3 years).

– The best for servers, but not for beginners!

● Fedora Core: http://fedora.redhat.com/

– Stable, secure, user friendly, easy to install. Frequent full releases.

● Ubuntu: http://www.ubuntu.com/

– Easy to install, secure, user friendly, frequent full releases,

● CentOS: http://www.centos.org/

– Very stable and safe based on RHEL

– Stable releases and best for servers

SOME FREE UNIX BASED SYSTEMS

● GNU / Hurd: http://www.gnu.org/software/hurd/hurd.html

– GNU tools with the Hurd, the GNU kernel (microkernel)

– Getting mature, but not enough yet for general use.

– Only used by Hurd developers so far (2004).

● BSD Family

– FreeBSD: http://www.freebsd.org/

● Powerful, multiplatform, secure, and popular BSD system

– OpenBSD: http://openbsd.org/

● Built for extreme security and reliability. Popular in Internet servers.

– NetBSD: http://netbsd.org/

● BSD distribution which goal is to be extremely portable● For example → available on ARM

LINUX DISTROS ANALOGY WITH CARS

● Best way to explain this is to make an analogy with engines and cars. Imagine a world where there is only one engine manufacturer. Everyone else gets the engine free of charge and makes a car around it. Each “car model” in Linux is called a Distribution or Distro. Examples:

– Debian, Red Hat Fedora, Ubuntu, Suse, Knoppix, PCLinuxOS, Back-Track

– And hundreds of others.

● The engine in Linux is the kernel. Check out - http://en.wikipedia.org/wiki/Linux_kernel

● Version numbering:

– A.B.C.D

● A – Kernel version● B – Kernel major version● C – Kernel minor version● D – Bug fixes

WHY LEARN LINUX AS OPPOSED TO OTHER OS ..?

● FREEDOM – who likes their freedom? How do you spell FREEDOM?

● Ans is Linux!

– Freedom from price

– Freedom from all sorts of entanglements

– Freedom – no licensing hassles, expenses, threats, court cases, not locked into a specific product or vendor, no costly upgrades every year

● WHY – because of Linux’s unique licensing.

LINUX KERNEL LICENSE

● Linux is Open Source Software – i.e. developed by a large community of developers working collaboratively since the source code is freely available to anyone to read and improve. And this cycle is iterative. The Internet is the medium for this development. The Linux kernel is released under the GNU General Public License version 2 (GPLv2).

● 4 types of licenses basically :

– Open Source – free and modifiable source code

– Closed Source – source code not available and costly end product

– Freeware – Closed source, but given away freely

– Shareware – Closed source, initially given away free but then requires payment for continued use.

ITS GOOD THING TO HAVE A WIDE SPECTRUM

● Each Operating System has its own advantages and disadvantages (some more some less)

● Don’t become biased, don’t fall in love with a specific OS, don’t be blinded. Evaluate your need(s) and choose accordingly.

REFERENCES

● http://en.wikipedia.org/wiki/Linux_kernel

● https://www.kernel.org

● http://spectrum.ieee.org/computing/software/the-strange-birth-and-long-life-of-unix/0

THANKS FOR YOU TIME.........!