Table of Contents
Introduction............................................................................................................................ 2
Why to use an operating system? .......................................................................................... 2
Basic importance of the operating system ............................................................................. 2
Examples of Operating System with Market Share ................................................................ 3
The History of Operating Systems .......................................................................................... 3
The First Generation (1940's to early 1950's)..................................................................... 4
The Second Generation (1955-1965).................................................................................. 4
The Third Generation (1965-1980) ..................................................................................... 4
The Fourth Generation (1980-Present Day) ....................................................................... 4
Types of Operating System (OS) ............................................................................................. 5
Batch Operating System...................................................................................................... 5
Multi-Tasking/Time-sharing Operating systems ................................................................. 5
Real time OS........................................................................................................................ 5
Distributed Operating System............................................................................................. 5
Network Operating System ................................................................................................. 5
Mobile OS ........................................................................................................................... 5
Functions of Operating System .............................................................................................. 5
Features of Operating System (OS) ........................................................................................ 7
Advantage of Operating System ............................................................................................. 7
Disadvantages of Operating System ....................................................................................... 7
Difference between 32-Bit and 64-Bit Operating System ...................................................... 8
What is Kernel in Operating System? ..................................................................................... 8
Features of Kernel ............................................................................................................... 8
Types of Kernel ................................................................................................................... 8
Monolithic........................................................................................................................... 8
Microkernels ....................................................................................................................... 9
Operating System
Made by Abdul Rahman Waseem, 232011
Introduction
An Operating System (OS) is a software that acts as an interface between computer hardware
components and the user. Every computer system must have at least one operating system to
run other programs. Applications like Browsers, MS Office, Notepad Games, etc., need some
environment to run and perform its tasks. The OS helps you to communicate with the computer
without knowing how to speak the computer's language. It is not possible for the user to use
any computer or mobile device without having an operating system.
Hardware
•CPU,Memory,Hard
Drive
Oprerating
System
•Windows,Apple
OS X,Linux
End User
Why to use an operating system?
An operating system brings powerful benefits to computer software and software development.
Without an operating system, every application would need to include its own UI, as well as
the comprehensive code needed to handle all low-level functionality of the underlying
computer, such as disk storage, network interfaces and so on. Considering the vast array of
underlying hardware available, this would vastly bloat the size of every application and make
software development impractical. Instead, many common tasks, such as sending a network
packet or displaying text on a standard output device, such as a display, can be offloaded to
system software that serves as an intermediary between the applications and the hardware. The
system software provides a consistent and repeatable way for applications to interact with the
hardware without the applications needing to know any details about the hardware. As long as
each application accesses the same resources and services in the same way, that system
software -- the operating system -- can service almost any number of applications. This vastly
reduces the amount of time and coding required to develop and debug an application, while
ensuring tat users can control, configure and manage the system hardware through a common
and well-understood interface.
Basic importance of the operating system
1. Operating system behaves as a resource manager. It utilizes the computer in a cost
effective manner. It keeps account of different jobs and the where about of their results
and locations in the memory.
2. Operating system schedules jobs according to their priority passing control from one
program to the next. The overall function of job control is especially important when
there are several uses (a multi user environment)
3. Operating system makes a communication link user and the system and helps the user
to run application programs properly and get the required output
4. Operating system has the ability to fetch the programs in the memory when required
and not all the Operating system to be loaded in the memory at the same time, thus
giving the user the space to work in the required package more conveniently and easily
5. Operating system helps the user in file management. Making directories and saving
files in them is a very important feature of operating system to organize data according
to the needs of the user
6. Multiprogramming is a very important feature of operating system. It schedules and
controls the running of several programs at ones
7. It provides program editors that help the user to modify and update the program lines
8. Debugging aids provided by the operating system helps the user to detect and rename
errors in programs
9. Disk maintenance ability of operating system checks the validity of data stored on
diskettes and other storage to make corrections to erroneous data
Examples of Operating System with Market Share
iOS
16%
Mac OS
4%
Windows
41%
Android
38%
OS Name
Share
Windows
Android
iOS
Mac OS
Linux
Chrome OS
Windows Phone OS
40.34
37.95
15.44
4.34
0.95
0.14
0.06
The History of Operating Systems
The first operating system was created by General Motors in 1956 to run a single IBM
mainframe computer. Other IBM mainframe owners followed suit and created their own
operating systems. As you can imagine, the earliest operating systems varied wildly from one
computer to the next, and while they did make it easier to write programs, they did not allow
programs to be used on more than one mainframe without a complete rewrite.
In the 1960s, IBM was the first computer manufacturer to take on the task of operating system
development and began distributing operating systems with their computers. However, IBM
wasn't the only vendor creating operating systems during this time. Control Data Corporation,
Computer Sciences Corporation, Burroughs Corporation, GE, Digital Equipment Corporation,
and Xerox all released mainframe operating systems in the 1960s as well.
in the late 1960s, the first version of the Unix operating system was developed. Written in C,
and freely available during it's earliest years, Unix was easily ported to new systems and rapidly
achieved broad acceptance. Many modern operating systems, including Apple OS X and all
Linux flavors, trace their roots back to Unix
Microsoft Windows was developed in response to a request from IBM for an operating system
to run its range of personal computers. The first OS built by Microsoft wasn't called Windows,
it was called MS-DOS and was built in 1981 by purchasing the 86-DOS operating system from
Seattle Computer Products and modifying it to meet IBM's requirements. The name Windows
was first used in 1985 when a graphical user interface was created and paired with MS-DOS.
Apple OS X, Microsoft Windows, and the various forms of Linux (including Android) now
command the vast majority of the modern operating system market.
The First Generation (1940's to early 1950's)
When electronic computers where first introduced in the 1940's they were created without any
operating systems. All programming was done in absolute machine language, often by wiring
up plugboards to control the machine's basic functions. During this generation computers were
generally used to solve simple math calculations, operating systems were not necessarily
needed.
The Second Generation (1955-1965)
The first operating system was introduced in the early 1950's, it was called GMOS and was
created by General Motors for IBM's machine the 701. Operating systems in the 1950's were
called single-stream batch processing systems because the data was submitted in groups. These
new machines were called mainframes, and they were used by professional operators in large
computer rooms. Since there was such as high price tag on these machines, only government
agencies or large corporations were able to afford them.
The Third Generation (1965-1980)
By the late 1960's operating systems designers were able to develop the system of
multiprogramming in which a computer program will be able to perform multiple jobs at the
same time.The introduction of multiprogramming was a major part in the development of
operating systems because it allowed a CPU to be busy nearly 100 percent of the time that it
was in operation. Another major development during the third generation was the phenomenal
growth of minicomputers, starting with the DEC PDP-1 in 1961. The PDP-1 had only 4K of
18- bit words, but at $120,000 per machine (less than 5 percent of the price of a 7094), it sold
like hotcakes. These microcomputers help create a whole new industry and the development of
more PDP's. These PDP's helped lead to the creation of personal computers which are created
in the fourth generation
The Fourth Generation (1980-Present Day)
The fourth generation of operating systems saw the creation of personal computing. Although
these computers were very similar to the minicomputers developed in the third generation,
personal computers cost a very small fraction of what minicomputers cost. A personal computer
was so affordable that it made it possible for a single individual could be able to own one for
personal use while minicomputers where still at such a high price that only corporations could
afford to have them. One of the major factors in the creation of personal computing was the
birth of Microsoft and the Windows operating system. The windows Operating System was
created in 1975 when Paul Allen and Bill Gates had a vision to take personal computing to the
next level. They introduced the MS-DOS in 1981 although it was effective it created much
difficulty for people who tried to understand its cryptic commands. Windows went on to
become the largest operating system used in techonology today with releases of Windows 95,
Windows 98, WIndows XP (Which is currently the most used operating system to this day),
and their newest operating system Windows 7. Along with Microsoft, Apple is the other major
operating system created in the 1980's. Steve Jobs, co founder of Apple, created the Apple
Macintosh which was a huge success due to the fact that it was so user friendly. Windows
development throughout the later years were influenced by the Macintosh and it created a
strong competition between the two companies. Today all of our electronic devices run off of
operating systems, from our computers and smartphones, to ATM machines and motor
vehicles. And as technology advances, so do operating systems.
Types of Operating System (OS)
Following are the popular types of Operating System:
 Batch Operating System
 Multitasking/Time Sharing OS
 Multiprocessing OS
 Real Time OS
 Distributed OS
 Network OS
 Mobile OS
Batch Operating System
Some computer processes are very lengthy and time-consuming. To speed the same process, a
job with a similar type of needs are batched together and run as a group. The user of a batch
operating system never directly interacts with the computer. In this type of OS, every user
prepares his or her job on an offline device like a punch card and submit it to the computer
operator.
Multi-Tasking/Time-sharing Operating systems
Time-sharing operating system enables people located at a different terminal(shell) to use a
single computer system at the same time. The processor time (CPU) which is shared among
multiple users is termed as time sharing.
Real time OS
A real time operating system time interval to process and respond to inputs is very small.
Examples: Military Software Systems, Space Software Systems are the Real time OS example.
Distributed Operating System
Distributed systems use many processors located in different machines to provide very fast
computation to its users.
Network Operating System
Network Operating System runs on a server. It provides the capability to serve to manage data,
user, groups, security, application, and other networking functions.
Mobile OS
Mobile operating systems are those OS which is especially that are designed to power
smartphones, tablets, and wearables devices. Some most famous mobile operating systems are
Android and iOS, but others include BlackBerry, Web, and watchOS.
Functions of Operating System
Below are the main functions of Operating System:
In an operating system software performs each of the function:
1. Process management:Process management helps OS to create and delete processes. It also provides
mechanisms for synchronization and communication among processes.
2. Memory management:Memory management module performs the task of allocation and de-allocation of
memory space to programs in need of this resources.
3. File management:It manages all the file-related activities such as organization storage, retrieval, naming,
sharing, and protection of files.
4. Device Management:
Device management keeps tracks of all devices. This module also responsible for this
task is known as the I/O controller. It also performs the task of allocation and deallocation of the devices.
5. I/O System Management:
One of the main objects of any OS is to hide the peculiarities of that hardware devices
from the user.
6. Secondary-Storage Management:
Systems have several levels of storage which includes primary storage, secondary
storage, and cache storage. Instructions and data must be stored in primary storage or
cache so that a running program can reference it.
7. Security:Security module protects the data and information of a computer system against
malware threat and authorized access.
8. Command interpretation:
This module is interpreting commands given by the and acting system resources to
process that commands.
9. Networking:
A distributed system is a group of processors which do not share memory, hardware
devices, or a clock. The processors communicate with one another through the network.
10. Job accounting:
Keeping track of time & resource used by various job and users.
11. Communication management:
Coordination and assignment of compilers, interpreters, and another software resource
of the various users of the computer systems.
Features of Operating System (OS)
Here is a list important features of OS:
 Protected and supervisor mode
 Allows disk access and file systems Device drivers Networking Security
 Program Execution
 Memory management Virtual Memory Multitasking
 Handling I/O operations
 Manipulation of the file system
 Error Detection and handling
 Resource allocation
 Information and Resource Protection
Advantage of Operating System
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Allows you to hide details of hardware by creating an abstraction
Easy to use with a GUI
Offers an environment in which a user may execute programs/applications
The operating system must make sure that the computer system convenient to use
Operating System acts as an intermediary among applications and the hardware
components
It provides the computer system resources with easy to use format
Acts as an intermediator between all hardware’s and software’s of the system
Disadvantages of Operating System
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If any issue occurs in OS, you may lose all the contents which have been stored in your
system
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Operating system’s software is quite expensive for small size organization which adds
burden on them. Example Windows
It is never entirely secure as a threat can occur at any time
Difference between 32-Bit and 64-Bit Operating System
Below are the Key Differences between 32-Bit and 64-Bit Operating System:
Parameters
32. Bit
64. Bit
Allow 32 bit of data Allow 64 bit of data
Architecture and Software
processing simultaneously
processing simultaneously
32-bit applications require 64-bit applications require a
Compatibility
32-bit OS and CPUs.
64-bit OS and CPU.
All versions of Windows 8, Windows XP Professional,
Windows 7, Windows Vista, Vista, 7, Mac OS X and
Systems Available
and Windows XP, Linux, etc. Linux.
32-bit systems are limited to 64-bit systems allow a
Memory Limits
maximum 17 Billion GB of
3.2 GB of RAM.
RAM.
What is Kernel in Operating System?
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. It makes the communication between the hardware and
software possible. While the Kernel is the innermost part of an operating system, a shell is the
outermost one
Features of Kernel
Low-level scheduling of processes
Inter-process communication
Process synchronization
Context switching
Types of Kernel
There are many types of kernels that exists, but among them, the two most popular kernels are:
Monolithic
A monolithic kernel is a single code or block of the program. It provides all the required
services offered by the operating system. It is a simplistic design which creates a distinct
communication layer between the hardware and software.
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Microkernels
Microkernel manages all system resources. In this type of kernel, services are implemented in
different address space. The user services are stored in user address space, and kernel services
are stored under kernel address space. So, it helps to reduce the size of both the kernel and
operating system.