Operating System

1. OPERATINGSYSTEM
Instructor: Sara Hassan
Introduction to Information and
Communication Technologies
Ghazi University, Dera Ghazi Khan

2. What is operating system?
Definition:
• An operating system (OS) is a
collection of software that
manages computer hardware
resources .
• It is a low-level software program
that enables the computer
hardware to communicate and
operate with the computer
software.
Without a computer operating system, a
computer would be useless
“The operatingsystemactsasa Interface
Betweenthe user and computer
hardware”

4. Operations Of OS
•Processor Management: An operating system manages the processor’s
work by allocating various jobs to it and ensuring that each process
receives enough time from the processor to function properly.
•It manages all of the software and hardware on the computer
•Manage Memory: An operating system manages the allocation and
deallocation of the memory to various processes and ensures that the
other process does not consume the memory allocated to one process.
•Device Management: There are various input and output devices. An OS
controls the working of these input-output devices. It receives the
requests from these devices, performs a specific task, and communicates
back to the requesting process.

5. OperationsOfOS
•Start and shut down a computer
•Establish An Internet Connection
•Provide a user Interface
•Error Detection: From time to time, the operating system checks the
system for any external threat or malicious software activity. It also checks
the hardware for any type of damage. This process displays several alerts to
the user so that the appropriate action can be taken against any damage
caused to the system.

6. Components of Operating System
The operating system has two components:
•Shell
•Kernel

7. Shell
Shell handles user interactions. It is the outermost layer of the OS and
manages the interaction between user and operating system by:
•Prompting the user to give input
•Interpreting the input for the operating system
•Handling the output from the operating system.
Shell provides a way to communicate with the OS by either taking the
input from the user or the shell script. A shell script is a sequence of
system commands that are stored in a file.

8. Kernel
The kernel is the central component of a computer operating
systems. The only job performed by the kernel is to the manage the
communication between the software and the hardware. A Kernel is
at the nucleus of a computer. The Kernel is the innermost part of an
operating system, a shell is the outermost one.
Kernel is a computer program that manages Input/Output requests
from software and transfer them into data processing instructions
for CPU and other electronic components of computer.

10. Structure Of operating system
User Interface
•User interact with operating system
Kernel
•Core of operating system, responsible for loading
operating system

11. Characteristics OfOperatingSystem
Operating
System
GUI Multiuser Multitasking Multiprocessing Multithreading

12. • GUI
• GUI- Short for Graphical User Interface, a GUI Operating System contains
graphics and icons and is commonly navigated by using a computer mouse.

13. • Multi-user
• Multi-user -A multi-user operating system allows for
multiple users to use the same computer at the same
time and/or different times example (LINUX)

14. • Multi T
asking
• An operating system that is capable of allowing multiple software
processes to run at the same time.
Below are some examples of multitasking operating systems.
• Unix
• Windows XP
• Windows Vista

15. • Multi Processing
• An operating system capable of supporting and utilizing more than one
computer processor.
More than one CPUs that can be shared
Below are some examples of multiprocessing operating systems.
For Example
• Linux
• Unix
• Windows 2000

16. • Multi Threading
• Operating systems that allow different parts of a software program to run
concurrently
For example
• Linux
• Unix
• Windows 2000

17. Real – Time:
- responds to input instantly. General-purpose
operating systems, such as DOS and UNIX, are not
real-time.

18. Command Line Interface (CLI)
• The command line interface is a user interface that is
navigated by typing commands at prompts, as opposed to
using the mouse to perform a command.
• Because a command line interface requires unique
commands, this interface is often more difficult to learn
because of the need to memorize dozens of different
commands.

19. CLI

20. Types of operatingsystem
 Stand Alone operating system.
 Server operating system.
 Embedded operating system.

21. Stand Alone operating system
A standalone OS is an OS that runs on a device like a
notebook, desktop computer, or laptop. A standalone
operating system offers a complete functioning framework.

22. Stand
Alone
operating
system
WINDOWS
MAC OS
LINUX
Stand Alone operating system/Desktop operating system

23. Microsoft Windows
• Microsoft created the Windows operating system in the
mid-1980s. Over the years, there have been many
different versions of Windows, but the most recent ones
are Windows 10, Windows 8, Windows 7. Windows
comes preloaded on most new PCs, which helps to make
it the most popular operating system in the world.

24. Microsoft Windows
If you're buying a new computer or are upgrading to
a newer version of Windows, you can choose from
several different editions of Windows, such as Home
Premium, Professional, and Ultimate. You may need
to do some research to decide which edition is right
for you.

25. Advantages & Disadvantages of Windows
Advantages:
•Easy to use
•Update
Disadvantages:
•Expensive
•Not secure

26. Windows 7

27. Windows 10

28. Mac OS
• Mac OS is a line of operating systems created by
Apple. It comes preloaded on all new Macintosh
computers, or Macs. All of the recent versions are
known as Mac OS X (pronounced Mac O-S Ten)

29. Advantages & Disadvantages Of MACOS
Advantages:
•Great GUI
•Secure
•Better to graphic designer
Disadvantages:
•Not all software run
•expensive

30. Linux
Linux is a family of open source operating systems,
which means that they can be modified and
distributed by anyone around the world. This is very
different from Windows, which can only be modified
by the company that owns it (Microsoft).

31. Advantages & Disadvantages of LINUX
Advantages:
•Free
•Low PC requirement
•Secure
Disadvantages:
•Not all software run
•Hard to learn use and install

32. Server Operating system
• A server operating system (OS) is a type of operating system
that is designed to be installed and used on a server
computer.
• Server operating systems are designed to provide platforms for multi-
users , for critical, network applications.
• It is an advanced version of an operating system
• Their main purpose is to provide security, stability and collaboration.
• Some common examples of server OSs include:
•Windows Server
•Mac OS X Server

33. Embedded operating system
•An embedded operating system is a specialized operating system
(OS) designed to perform a specific task for a device that is not a
computer.
•An embedded operating system main job is to run that allowed
device to do its job.
•Examples of embedded OS are MP3 players, digital cameras, DVD
player, mobile phones

34. Operating System on Mobile Devices
• Mobile devices such as phones, tablet computers, and
mp3 players are very different from desktop and laptop
computers, so they run operating systems that are
designed specifically for mobile devices. Examples of
mobile operating systems include Apple iOS, Windows
Phone, and Google Android.

35. Operating
System on
Mobile
Devices