CONCEPTS OF OPERATING SYSTEMS

 In this article, we will be going through some of the basics of Operating System. You can learn about Operating systems services, components and it’s modes.

WHAT IS AN OPERATING SYSYTEM?

A program that acts as an intermediary between a user of a computer and the computer hardware or in other words it is an interface between computer system and hardware. An operating system is a software which performs all the basic tasks like file management, memory management, process management, handling input and output, and controlling peripheral devices such as disk drivers and printers.

OVERVIEW OF OPERATING SYSTEM:

·        Operating system goals

·        Operating system services

·        System Calls

·        Operating system design and implementation

·        Operating system structures

·        Operating system operations

·        Operating system modes

OPERATING SYSTEM SERVICES:

Operating systems provide an environment for execution of programs and services to programs and users

One set of operating-system services provides functions that are helpful to the user:

1.     User interface - Almost all operating systems have a user interface (UI). Varies between Command-Line (CLI), Graphics User Interface (GUI),   Batch

 

2.     Program execution - The system must be able to load a program into memory and to run that program, end execution, either normally or abnormally (indicating error)

 

 

3.     I/O operations -  A running program may require I/O, which may involve a file or an I/O device

 

4.     File-system manipulation -  The file system is of particular interest. Programs need to read and write files and directories, create and delete them, search them, list file Information, permission management.

 

5.     Communications – Processes may exchange information, on the same computer or between computers over a network

 

 

6.     Error detection – OS needs to be constantly aware of possible errors May occur in the CPU and memory hardware, in I/O devices, in user program

 

7.     Resource allocation - When  multiple users or multiple jobs running concurrently, resources must be allocated to each of them

Many types of resources -   CPU cycles, main memory, file storage, I/O devices.

 

8.     Accounting - To keep track of which users use how much and what kinds of computer resources

9.     Protection and security - The owners of information stored in a multiuser or networked computer system may want to control use of that information, concurrent processes should not interfere with each other

Protection involves ensuring that all access to system resources is controlled

Security of the system from outsiders requires user authentication, extends to defending external I/O devices from invalid access attempts

Components of an Operating System:

A lot of us hear the term operating system and think of the interfaces of our desktops and phones like the menus, buttons, and backgrounds. Technically, these are part of the operating system, but it’s a little more complex than that. An operating system is a whole package that manages our computer resources and lets us interact with them. There are two main parts to an operating system, the kernel, and the user-space.

The kernel is the main core of an operating system. It talks directly to our hardware and manages our systems resources. As users, we don’t interact with the kernel directly. Instead, we interact with the second part of an operating system the, user space. The user space is basically made up of everything outside the kernel.