Definition of operating system: An operating system is defined as, ‘It is a software component of a computer system and/or machine system that is responsible for managing various activities of the system as well as for sharing of system resources’. It hosts the several applications that run on system and handles the operations of internal and external hardware devices. End users interact with operating system through two interface techniques:
- Command line interface (CUI)
- Graphical user interface (GUI)
Hence, we can say that the behavior of operating system deals among computer system and end users. In short, it enables user interaction with computer system by acting as an interface between users or application programs and the attached computer hardware. Sometimes its call by the name of OS, which full form, is operating system.
In other words OS can be defined as, ‘an OS is a set of program that acts as an intermediary between the end users and the computer hardware’.
Services provided by operating system:
Operating system plays an important role in between communicating system software and hardware devices. The functionality of operating system is not restricted to just providing the interface environment although its offers a more important and necessary services and/or functionality to both end users and application programs. Some of the main services of operating system are listed below.
- System initialization:
It’s responsible of initializing the program, loading the programs and transfers the program between main memory and the secondary memory of the computer system. An operating system is the first program which is automatically loaded when the system is under booted stage or switched ON.
- Routines provider:
One of the most important service provided by the OS, that is providing routines to handling input/ output requests. It supervise the connected input/ output devices and incorporating specialized input/ output routines.
- Driver configuration:
Most of the connected peripheral devices have its own drives to perform operation and/or providing interface. These peripheral devices need to be installed for the operating system to enabling communication with devices. Hence device drivers accompany operating system and enable the system to be configured for specific hardware.
- Memory allocation:
To allocating the required memory space to the processes and manage the database of the memory allocation done by operating system
- File management/handling system:
This service of OS allows to the authorized user to file management and/or file handling functionality, located in the system memory (either, main memory and/or secondary memory). This service responsible to enable the user to manipulate the program, data files contents and managing the stored location of the file.
- Security services:
To protect the system form the unauthorized access and information crash/damage. It provides privacy policies that ensure secure access to authorized user. This service achieve through the use of password and access rights.
Goals of operating system:
There are many important goals of an OS, some of them are listed below;
- It simplifies the execution of user programs and makes solving user problems easier.
- It allows efficiently sharing of hardware and/or software resources computer systems.
- It allows to makes software application portable and versatile.
- Provide isolation, security and protection among user programs.
- Make system more reliable and reduce error confinement, fault tolerance and reconfiguration.