This document provides an introduction to Linux, including: - What Linux is, its basic components like the kernel and shell, and features such as being open-source and portable. - The architecture of Linux including the hardware, kernel, shell, and utilities layers. - Popular Linux distributions like Debian, Red Hat Enterprise Linux, and SUSE Linux Enterprise. - A comparison between Linux and Windows in areas like licensing, updating processes, and software availability. - Important Linux commands for navigation, file management, networking, and package management. - An overview of the Linux file system structure and common directories like /bin, /etc, and /var.

1. Introduction to Linux
Knowledge sharing session
Part 1

2. Contents
 What is Linux ?
 Basic Componentsof Linux
 Basic Features of Linux
 Architectureof Linux
 Distributionof Linux
 Comparison between Linuxwithwindows Operating System.
 Important Commands of Linux
 Linux File system.
 How to Configure Network in Linux (LAB).
 How to Update Oracle Linux OS (LAB).
 How to Extend and mount disk in Linux OS (LAB).

3. What is Linux ?
 Linux is a free and open-source operating system that is
based on the Linux kernel.
 Linux Is a file based Operating system.
 It is known for its stability, reliability, and security.
 Its is a Unix clone written from scratch by Linus
Torvalds.
 Linux is used in various fields like Android , Routers ,
transmitting devices and Game Designing .

4. Components of Linux System
 Kernel − Kernel is the core part of Linux. It is responsible for
managing the system's resources, such as the CPU, memory,
and storage.
 System libraries− System libraries are special functions or
programs using which application programs or system
utilities accesses Kernel's features
 Shell - is a command-line interpreter that provides a way
for users to interact with the kernel.
 System Utility − System Utilities are programs that
provides basic functionality to the Linux system such us basic
Linux commands ls, cp , mv , rm , ...

5. Basic Features of Linux
 Open Source − Linux is freely available and open source
software, which means that anyone can download, modify,
and distribute it
 Portable − Linux can be run on a wide variety of hardware
platforms. This makes it a very versatile and flexible
operating system.
 Multi-user and multitasking: Linux is a multi-user operating
system, which means that multiple users can log in and use
the system simultaneously.
 Security − Linux is generally considered to be a very secure
operating system. This is due to its open source nature,
which allows security vulnerabilities to be discovered and
patched quickly.

6. Basic Features of Linux
 Command-line interface: Linux has a powerful command-
line interface (CLI) that allows users to interact with the
system and perform tasks without having to use a graphical
user interface (GUI).
 Graphical user interface (GUI): Linux also supports graphical
user interfaces (GUIs), which provide a more user-friendly
way to interact with the system.
 Customization: Linux is highly customizable, allowing
users to tailor the operating system to their specific needs
and preferences.

7. Architecture of Linux Operating System

8. The architecture of Linux contains some layers :
 Hardware layer − Hardware consistsof all
peripheral devices (RAM/ HDD/ CPU etc).
 Kernel − It is the core component of Operating System,
interactsdirectlywith hardware, provides low level
services to upper layercomponents.
 Shell − It takescommands from the userand
executes kernel's functions.
 Utilities − Utility programs that provide the user mostof
the functionalitiesof an operating systems.

9. Distribution of Linux
The choice and the ever increasing number of Linux distributions
can be confusing for those who are new to Linux.
The three major base Linux distributions are:
 Debian: Debian is a stable and reliable distribution that is
well-suited for both beginners and experienced users alike. It
has a large community of users and developers who provide
support and resources. Ex, Debian , Ubuntu , Kali , etc..
 Red Hat Enterprise Linux (RHEL): RHEL is a commercial
distribution that is known for its stability, security, and
reliability. It is a good choice for businesses and organizations
that need a reliable and well-supported Linux distribution.
Ex, Red Hat , CentOS , Oracle Linux , et..

10. Distribution of Linux
 SUSE Linux Enterprise: SUSE Linux Enterprise is another
commercial distribution that is known for its stability,
security, and reliability.
Ex, OpenSUSE

11. Linux v/s Windows
 Linux is freely available or online downloads, for
windows companies have pay for their license.
 Windows need up to date time to time, its updating process
is slower than Linux.
 Linux supports backward compatibility unlike to the
windows.
 Unlike Windows Linux support multiple simultaneous login
 Most of the software made on the windows are need to be
licensed but in Linux all of them are freely available.

12. Commands of Linux
 Navigation Commands
These commands are used for navigating and manipulating files and directories on a Linux
system.

13. Commands of Linux
 File Management Commands
These Linux commands allow you to manage files and directories
on your system.

14. Commands of Linux
 Network and Connectivity Commands
Linux provides a wide range of tools for configuring and troubleshooting network
connections.

15. Commands of Linux
 Package Management Commands
These Linux commands allow you to install, update, and remove
software packages on your system.

16. Linux File System
 A Linux file system is a hierarchical, tree-like structure that stores
and organizes files and directories on a computer.
 In Linux, everything is a file, including devices, programs, and
system information.
 The Linux file system tree is rooted at the root directory (/).
 Several types of object exist in the filesystem.
-Normal Files :-Includes text files, graphics files, executable, etc.
-Directories :- Directories contain named 'links' to other files
-Device Files :- Devices (disks, tape drives , etc) are identified by device file.
-Symbolic Links:- References to files located at other points in the file system.
 File names can be up to 255 characters long which are Case sensitive.
 All characters except '/' are legal in filenames '/' is used as a separator in path
names.
 Network File System are physically somewhere else, but appear as if they
are mounted on one computer.

17. Linux File System
Root Structure

18. Linux File System
Brief Description
 /(root) :-The root filesystem is the top-level directory of the filesystem.
It must contain all of the files required to boot the Linux system before other
filesystems are mounted.
 /bin :- The /bin directory contains user executable files.
 /boot:- Contains the static bootloader and kernel executable and
configuration files required to boot a Linux computer.
 /dev:- This directory contains the device files for every hardware device
attached to the system.
 /etc : Contains the local system configuration files for the host 17
Computer.
 /media:- A place to mount external removable media devices such as USB
thumb drives that may be connected to the host.
 /mnt:- A temporary mountpoint for regular filesystems (as in not
removable media) that can be used while the administrator is
repairing or working on a filesystem.

19. Linux File System
Brief Description
 /opt:- Optional files such as vendor supplied application programs
should be located here.
 /sbin:- System binary files. These are executables used for system
Administration.
 /tmp:- Temporary directory. Used by the operating system and many
programs to store temporary files.
 /usr:- These are shareable, read-only files, including executable binaries
and libraries, man files, and other types of documentation.
 /var:- Variable data files are stored here. This can include things like log
files, MySQL, and other database files, web server data files, email
inboxes, and much more.

20. Thank You