Introduction of Operating System
Operating system is an interface between computer and hardware and application software. Without OS no computer can be operated. Operating system is regarded as the heart of living being for a computer system.
In other words, OS is defined as a program or suit (support for) of programs that controls the entire operation of the computer, such as recognizing input from keyboard, sending output to the display screen keeping track of files and directories on the disk and controlling peripheral devices such as disk drives and printers.
Roles of operating system
- Operates CPU of the computer.
- Providing a user interface.
- To control and coordinate peripheral devices such as printers, screens, disk drivers.
- To help users to develop programs
- Managing the computers memory.
- Backup and recovery is possible.
- Manage the hardware.
Functions of Operating System
The main function of an operating system is to manage the resources such as memory and files of the computer system. The operating system also resolved the conflicts that arise when two users or programs request the same resources at the same time.
Therefore it is also called the resource manager of a computer. Some of the important functions of an operating system are:
1. Process management
It manages the processes running in the computer system process. A process is basically a program that is being currently run by a user or a computer.
Example: A word processor application program such as MS Word runs processes in a computer system.
2. Memory Management
It manages the memory resources of a computer system. There are various resources for computers including primary memory or Random-Access Memory (RAM) and secondary memory like CDs and HDs.
All the programs are loaded in the main memory before their execution. It is the function of the operating system to determine how much memory we should provide at each process.
3. File Management
It manages the files and directories of a computer system. A file can be defined as a collection of information or data that is stored in the memory of a computer system.
Every file has a unique mane associated with it. The organization of files and directories in a computer system is referred to as a file system. An operating system allows users to create, modify, save or delete files in a computer system.
4. Device Management
The operating system deals with the management of peripheral devices such as printer, mouse and keyboard attached to a computer system.
An operating system interacts with the hardware devices through a specific device driver. The primary task of the operating system is to manage the input/ output operation performed by end-users.
5. Security Management
It ensures security for a computer system from various threats such as virus attack and unauthorized access.
An operating system uses various technologies such as authentication, authorization, cryptography, etc. for ensuring the security of a computer system.
6. Input/output Management
What output will come from the input given by the user, the operating system runs this program. This management involves coordinating various input and output devices. It assigns the functions of those devices where one or more applications are executed.
7. Job Priority
The work of job priority is creation and promotion. It determines what action should be done first in a computer system.
8. Special Control Program
The operating systems make automatic changes to the task through specific control programs. These programs are called Special Control Program.