Definition: An Operating System (OS) is a program that acts as an intermediary between the user of a computer and the computer hardware.
Purpose: Enables hardware components to function and provides an interface for users to interact with the computer.
Key Functions:
Controls the execution of application programs.
Acts as an interface between applications and hardware.
Objectives of Operating Systems
Main Objectives:
Convenience: Simplifies interaction between user and computer.
Efficiency: Optimizes resource use.
Evolution: Adapts to solve problems and accommodate new hardware or services.
Services Provided by Operating Systems
Key Services:
Program Development: Facilitates the creation of software.
Program Execution: Manages running applications.
I/O Device Access: Controls input and output devices.
File System Management: Handles access to file systems.
Error Detection and Response: Identifies and responds to errors in operation.
Components of a Computer System
System Components:
Hardware: Central Processing Unit (CPU), memory, I/O devices.
Operating System: Software that runs hardware and manages resources.
Application Programs: Software applications that perform specific tasks.
Users: Can be people or other machines.
Abstract View of the System
User Interaction:
Users (people or systems) interact with application programs.
Application programs communicate with the operating system, which interfaces with computer hardware.
Evolution of Operating Systems
Reasons for Evolution:
Hardware upgrades.
Introduction of new hardware.
Provision of new services.
Stages of Evolution:
Serial Processing
Simple Batch System
Multi-Programming Batch System
Time Sharing System
Parallel System
Distributed System
Real Operating System
Conclusion
The lecture covers the fundamental concepts and objectives of operating systems, their services, components, and evolution. Operating systems are crucial for the functionality of computer systems and their continuous development.