We are all using computers and how many of them think about operating systems (OS)?Operating system is considered as the backbone of the computer system. Let us see detail about OS.
What is an Operating System?
An operating system is an important part of every computer system. It is a program that manages the computer hardware. It also provides a basis for application programs and acts as intermediary between a user of the computer and computer hardware A computer system can be divided into four components.
· Hardware
· Operating System
· Application Programs
· Users
Different Types of Operating Systems
Different Types of Operating Systems
Mainframe operating systems are designed to optimize utilization of hardware.
Personal computer operating systems support complex games and business applications.
Handheld computer operating systems are designed to provide an environment in which a user can easily interface with the computer to execute programs.
The hardware has the central processing unit (CPU), the memory and an input/output (I/O) device provides the basic computer resources.The application programs such as word processors,spreadsheets,compilers and web browsers defines the ways in which these resources are used to resolve the computing problems of the users. The operating system controls and coordinates the use of the hardware among the various application programs for the various users. The components of a computer system are its hardware, software and data. The operating system provides the use of these resources in the operation of the computer system.
Operating system can be explored from two viewpoints
· the user and
· the system
User view
The user view of the computer varies by the interface being used. This can be explained by using three cases.
Case (1):
Many computer users sit in front of a pc consisting of a monitor, keyboard, mouse and system unit. Such a system is designed for one user to monopolize its resources. Hence the work is maximized that the user is performing. In this case the operating system is designed for ease of use, high performance and no utilization of resources.
Case (2):
Some users sit at a terminal connected to a mainframe or minicomputer. Other users are accessing the same computer through other terminals. These users share the resources and may exchange information. The operating system is designed to maximize resource utilization to assure that all available CPU time, memory and I/O are used efficiently and that no individual user takes more than their share.
Case (3):
Other users sit at workstations, connected to networks of other workstations and servers. These users have dedicated resources at their disposal but they also share resources such as networking and servers like file, compute and print servers.Therefore,the operating system is designed to compromise between individual usability and resource utilization.
System View
From the computers point of view, the operating system is the program that is most intimate with the hardware.
· The operating system can be viewed as a resource allocator.
A computer system has many resources such as hardware and software that may be required to solve the problem like CPU time, memory space, file storage space and I/O devices and so on.
· The operating system acts as the manager of these resources.
The operating system must decide how to allocate the resources to specific programs and users so that it can operate the computer system efficiently and fairly.
· An operating system is a control program
A control program manages the execution of user programs to prevent errors and improper use of the computer. It is concerned with the operation and control of I/O devices.
Operating systems exist to solve the problem of creating a usable computer system. The main goal of operating systems is to execute user programs and to make solving user problems easier. Hence computer hardware is constructed. Since the hardware alone is not easy to use, application programs are developed. These programs require certain common operations such as controlling the I/O devices. The common functions of controlling and allocating resources are then brought together into one piece of software called operating system....
No comments:
Post a Comment