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Topic : Basics of Operating SystemsSub Topic : Various Operating Systems

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Recap

In the last class, you have learnt about

• History of Operating System

• Need and definition of the operating system

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Objectives

On completion of this period, you would be able

to know

• The Classification of Operating System

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Classification of Operating System

Classification is based on:

• Interface

• Number of users

• Response time and program / job execution

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Operating Systems Based on User Interface

• Character Based:- Commands are entered using

keyboard only to perform an operation

Ex:-UNIX, MS-DOS

• Graphical User Interface :-Either keyboard or

mouse is used to perform an operation

Ex:- Windows, Macintosh, LINUX

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Example

Creation of file in MS-DOS Mode:• C:\> COPY CON filename.txt

• Then press enter key

• Type the data

• Press control key+z , to save the file

Creation of file in Windows mode: Click on the following

• Start Programs Accessories notepad

Now notepad window will be opened, type the data and save the file

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Based on Number of Users

• Single-User

Ex:- MS-DOS, Windows

• Multi-User

Ex:-UNIX, XENIX, LINUX etc.,

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Single-User, Single-Task Operating System

• Operating system manages one user account

• Only one program will be under execution at any

time

Ex:- MS-DOS

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Single User, Multi Task Operating System

• Can keep many user accounts, but not

simultaneously

• Several programs / tasks may be under execution

at the same time

• Used in desktop, and laptop computers

Ex:- Windows 9X, OS/2 etc.,

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Based on Response Time and Mode of Program Execution

• Batch Processing

• Multi – Programming

• Time Sharing

• Real time

• Hybrid

Batch Operating System

• Batch processing is execution of a series of programs ("jobs") on a computer without manual intervention

• A program takes a set of data files as input, process the data, and produces a set of output data files

• In "batch processing" the input data are collected into batches on files and are processed in batches by the program

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Batch Operating System (contd..)

• Used in mainframe computers

Benefits

• It allows sharing of computer resources among

many users and programs

• It avoids idling the computing resources with

minute-by-minute manual intervention and

supervision

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Multi-User Operating System

• Can keep many users account concurrently (many

users working in the system at the same time)

• Can execute several programs simultaneously

Ex :- UNIX

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Network Operating System

• Provides multi-user environment

• Provides network services and communications

Ex:- Windows NT, Novell Netware, Windows

Server 2003

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Summary

• Operating system are classified based on : Interface, Number

of users, Processing mode

• MS-DOS : Single user – Single task, character mode OS

• Windows : Single user – Multitasking, GUI mode OS

• UNIX : Multi-user, Multi-tasking OS

• Batch, Multiprogramming, Time Sharing, Real-Time, Hybrid

Operating Systems are based on response time and mode of

program execution

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Frequently Asked Questions

1. Write the classification of Operating Systems

2. Write the Operating System processing modes

3. Name any five Operating Systems

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Quiz

1. Which is the single-user, single-tasking

Operating System ?

a. MS-DOS

b. WINDOWS

c. UNIX

d. MACINTOSH

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Quiz

2. Which is the Multi-user Operating System ?

a. MS-DOS

b. WINDOWS

c. UNIX

d. MACINTOSH

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Previous question papers for operating systems

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