Structure of operating system

Operating system performs three functions:
*Convenience: An OS makes a computer more convenient to use.
*Efficiency: An OS allows the computer system resources to be used in an efficient manner.
*Ability to evolve: An OS should be constructed in such a way as to permit an efective development, testing and introduction of new system functions without at the same time interfering with service.

Every operating system has its own internal structure in terms of file arrangement, memory management, storage management, etc, and the entire performance of the system depends on its structure.

The elementary approach to structure an operating system is simple structure. Simple structure OS systems are small, simple and limited systems. MS-DOS is an operating system designed with this approach.

Structure of MS-DOS

An operating system may process its workload serially or concurrently. That is resources of the computer system nay be dedicated to a single program until its completion, or they may be dynamically reassigned among a collection of active programs in different stages of execution.

The main element of an OS that a user sees is the graphical user interface or GUI. This is the display and the method of interaction that the user can take to manipulate the OS via the display.

For example, in a personal computer OS such as Windows 7, the user can see a desktop, a background and icons. These are manipulated by way of the keyboard and mouse usually. In a mobile computer OS such as Android, the user can see a main screen with icons that can be manipulated with his fingers, with stylus or by voice.
Structure of operating system

The User Interface

The User Interface
The operating system performs five basic functions in the operations of computer system providing a user interface, resource management, task management, file management. And utilities and support services.

The user interfaces the part of the operating system that allows you to communicate with it so you can load program, access files and accomplish other tasks.

Three main types of user interfaces are the command-driven, menu-driven, and graphical user interface.

The trend in user interfaces for operating systems and other software is moving away from the entry of brief and user commands, or even the selection of choices from menus options.

Instead most software provides an easy-to- use graphical user interface (GUI) that uses icons, bars, button, boxes, and other images.

GUIs rely on pointing devices like the electronic mouse or touch-pad to make selections that help you get things done.
The User Interface

Microcomputers

Microcomputers
Microcomputers are designed for a single-user environment and small business applications. However, more and more business people are using microcomputers for both multi-user networks and business applications.

For example, a business person can use a microcomputer to organize financial transactions, prepare corporate tax return to update the inventory that they provide solutions for most business applications.

A microcomputer uses a microprocessor as the central processing unit. Microprocessor can be very powerful despite their small size.

Currently, there are two major microcomputer systems available in the market. They are IBM-compatible system and the Apple system. Both system use different platforms (operating system) to control the hardware.

The IBM-compatible system uses a Windows operating system developed by Microsoft. The Windows operating system provides a graphical user interface (GUI) and a multitasking environment. The Windows operating system dominate most of the microcomputer operating system market.

Apple’s Macintosh uses a totally different operating system developed by Apple Computer. However, it is suggested that the average business person use IBM system because of greater compatibility, wider program availability, and more open platform.
Microcomputers