Linus Torvalds created the Linux kernel in 1991 as an open source alternative to UNIX. It uses a monolithic kernel architecture and is highly portable, running on many platforms. Linux distributions package the kernel and applications, with the most popular being Debian, Gentoo, and Arch Linux, each using different package management systems. The Linux Foundation was formed in 2007 to standardize and promote Linux adoption.

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2. What Is Linux...
Linus Torvalds was the chief developer of the project.
Released on 5th October, 1991 .
Since beginning it was released as a free and open source.
Linux is available in multiple languages and is supported by multiple platforms.
Monolithic Kernel is an distinct feature which distinguishes it from other Operating
Systems.
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3. Evolution Of Linux….
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UNIX
[1971]
• Developed at AT&T’s Labs by team lead by Dennis Ritchie and Ken Thompson.
• It’s Source Code was used for basic development of the project
GNU
[1988]
• The project was started by Richard Stallman.
• It provided the concept of free software to Linux Project .
• GNU General Public License was included in the Linux for purpose of issuing
license to the free user.
MINIX
[1990]
• Project was started by S.Tanenbaum and Linus Torvalds.
• Development of Linux Kernel was started during MINIX designing.
• Applications written for MINIX were used in Linux.

4. The Design…
Linux derives much of its basic design from principles
established in Unix.
Linux uses a monolithic kernel, which handles process
control, networking, and peripheral and file system access.
The GUI used by most Linux systems is built on top of an
implementation of the X Window System.
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5. X Window System Architecture
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6. Linux Interface….
Users operate a Linux-based system through two possible
methods provided.
CLI(Command Line Interface)
Shell is used for the purpose of implementing CLI.
Controls attached to the associated hardware(Used in
embedded systems).
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7. THE KERNEL….
The Linux kernel was released under the GNU General Public
License version 2 .
Development started with a task switcher in Intel 80386 assembly
language and a terminal driver.
Being a free software there have been many modulations and changes
based on the user and developers’ suggestions.
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8. KERNEL ARCHITECTURE...
Linux is written in the version of the C programming
language.
Device drivers and kernel extensions run in kernel
space(Ring O).
Linux enables separate execution of graphics
system ,separate from the kernel .
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9. FEATURES OF LINUX KERNEL…
Kernel possesses an ability to interrupt a task executing kernel code and
perform provides pre-emptive scheduling.
The Pre-emption patch improves latency, increases responsiveness, and
makes Linux more suitable for real-time applications.
Kernel provides a high portability to the OS , hence can be used for a
wide range of products i.e. , from Mainframe computers to the hand held
devices.
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10. Kernel Features….
Pre emption
Portability
Kernel Panic
Kernel Oops
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12. LINUX DISTRIBUTIONS….
Linux source code has been distributed on the basis of the package
management system used , they are basically divided into 3 categories.
Debian based
Gentoo based
Pacman based
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13. DEBIAN BASED DISTRIBUTIONS…
Debian GNU/Linux is a distribution that emphasizes on free software.
It is supported on multiple hardware platforms.
Debian distributions use the .deb package format and
the dpkg package manager.
Knoppix , Linux Mint , Ubuntu are popular examples of Debian based
Linux distribution.
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14. Gentoo Based Distributions…
It is designed to have highly optimized and frequently
updated software.
These distributions use the Portage package management
system .
Gentoox , Sabayon Linux , Chrome OS are popular examples
of gentoo based OS.
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15. Pacman Based Distributions..
They use the Pacman package manager.
They are capable of resolving dependencies and
automatically downloading and installing all necessary
packages.
Arch Linux , Frugalware Linux , Parabola Linux are the most
successful distributions of this type.
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16. The Linux Distributions..
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17. THE LINUX FOUNDATION…
Founded in 2007 by the merger of the Open Source Development
Lab (OSDL) and the Free Standards Group (FSG).
It promotes, protects, and standardizes Linux by providing a comprehensive
set of services to compete effectively with closed platforms.
It is constituted by 102 corporate members and multitude of individual
members who certify the new development done in the Linux code.
It also provide funds for the purpose of research and development in Linux.
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18. The Linux Implementations…
Android
Chrome OS
Ubuntu
Red Hat Linux
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