Operating System Lesson 1

Study Notes

What is an Operating System?

Operating System (OS) is the primary software managing computer hardware and software.
Acts as an intermediary between users and hardware, ensuring efficient operation.
Responsible for system software essential for booting and performing functions.
Operates as a resource allocator, managing resources and resolving conflicts.
Functions as a control program, regulating program execution to minimize errors.

Operating System Goals

Facilitate execution of user programs, thereby simplifying problem-solving.
Enhance convenience of computer use.
Optimize utilization of computer hardware.

Functions of Operating System

Process Management

Defines a process as a program currently in execution, requiring CPU time, memory, and I/O devices.
Processes can be dependent (sharing resources) or independent (avoiding memory overlap).
Prioritization of processes allows critical tasks to execute first for efficiency.

Memory Management

Memory consists of a vast array of addressable words or bytes, serving as a quick-access data repository.
Main memory is volatile, meaning data is lost when powered off.
Virtual memory utilizes a portion of permanent storage (like hard disks) as additional memory.
The OS tracks memory allocation, identifying which parts are in use and by which processes.

File Management

A file is a collection of related information created and stored in a defined format.
File systems manage data encoding, storage, and retrieval from devices such as hard disks.
The OS handles activities such as creating and deleting files and directories, manipulating file primitives, and backing up files on nonvolatile media.

Device Management (I/O Management)

Device controllers connect the CPU to actual devices, ensuring smooth operation.
Device drivers are OS components that facilitate communication between the CPU and device controllers.
An interrupt controller prioritizes and manages interrupt requests, ensuring orderly access to devices.
The OS assigns device responsibilities, manages access duration, and efficiently allocates and deallocates devices.

Security and Protection

OS employs password protection to safeguard user data against unauthorized access.
Implements access rights to files and directories, enabling information control in multiuser systems.
Ensures concurrent processes do not interfere, maintaining system integrity.

Control Over System Performance

OS monitors delays between device requests and system responses to evaluate performance.
Oversees overall system health, optimizing function and responsiveness.
Performance tracking facilitates troubleshooting and enhances operational efficiency.

Job Accounting

Maintains records of time and resources used by different processes for tracking and management purposes.

Description

This quiz explores the fundamentals of Operating Systems, focusing on what constitutes an operating system and its role in managing hardware and software. It distinguishes between system software and application software, providing a foundational understanding for further study.