UNIT 1
Learning Objective
Understand the purpose of the operating system
Distinguish between a resource, a program, and a process
Recognize critical resources and explain the behavior of semaphores
Describe various memory page replacement algorithms Describe how files are stored in secondary storage © Bharati Vidyapeeth’s Institute of Computer Applications and Management,, New Delhi-63, by Parul Arora.
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Introduction
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What is an Operating System?
Features of Mainframe Systems
Features of Desktop Systems
Discuss Multiprocessor Systems
Features of Distributed Systems
Features of Clustered System
Types of Real -Time Systems
Features of Handheld Systems
Features of Computing Environments
© Bharati Vidyapeeth’s Institute of Computer Applications and Management,, New Delhi-63, by Parul Arora.
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What is an Operating System?
• A program that acts as an intermediary between a user of a computer and the computer hardware.
• Operating system goals:
Execute user programs and make solving user problems easier.
Make the computer system convenient to use.
• Use the computer hardware in an efficient manner.
© Bharati Vidyapeeth’s Institute of Computer Applications and Management,, New Delhi-63, by Parul Arora.
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Computer System Components
1. Hardware – provides basic computing resources (CPU, memory, I/O devices).
2. Operating system – controls and coordinates the use of the hardware among the various application programs for the various users.
3. Applications programs – define the ways in which the system resources are used to solve the computing problems of the users (compilers, database systems, video games, business programs).
4. Users (people, machines, other computers).
© Bharati Vidyapeeth’s Institute of Computer Applications and Management,, New Delhi-63, by Parul Arora.
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Abstract View of System Components
© Bharati