Popular Operating Systems for PC

We have learned that an operating system is a program that controls and manages all operations in a computer system. Personal Computers (PCs) have brought about a revolution in the use of computer. Today a PC can be found in every small business or even at homes. There are many popular operating systems available for personal computer.

These are MS-DOS, MS-Windows, LINUX, UNIX, OS/2, Mac OS etc. Out of these the Windows operating system is the most popular one.

DOS

DOS stands for Disk Operating System. It was originally developed for the IBM and compatible personal computers in 1980. It was the most popular operating system until Microsoft released the Windows operating system. The Microsoft version of DOS was named MS-DOS. Another version called PC-DOS was also popular.

DOS is basically a single-user operating system. The DOS operating system supported file management, directory management, memory management as well as standard I/O devices and disk drives and printers in a PC. DOS also has a program called 'Command Interpreter' to execute commands typed through the keyboard. There are a number of built in commands for various operations in DOS. A set of utility programs are also supplied with DOS. These utilities help users to perform various activities like copying, editing and sorting files. DOS was a text based system. Users had to type in commands to do any task. More over it was intended for a single user. When advanced microprocessors were invented and also with development of micro computers hardware technology, DOS became inefficient in using the hardware capabilities. DOS is a most compact operating system. It required only the 16 bit processor (Intel 8086/88) and 640 Kilo Bytes of memory.

Windows Operating System

Windows is a Graphical User Interface (GUI) based operating system developed by Microsoft Corporation. Windows was developed with two main objectives:

(i) to provide an easy to use interface for users and

(ii) to make use of 32 bit microprocessor features.

In GUI, users can make use of the common graphical input device such as the mouse to start programs or select commands. Users can visually interact with the computer. This is much more easier than typing commands in the old DOS operating system.

In the Graphical User Interface, each application (program) has a window. The user can interact with the application through the window. All windows have menus, and a set of buttons to minimize, maximize or close the window. A menu is a list of commands in the application Users can select commands in a menu with the mouse. In Windows, users can easily launch programs or do file operations very easily. For example to start a program move the mouse pointer to the programs icon (icon is a small graphic picture that represents a program) on the screen and click on it. There is no need to memorize any command. The GUI working environment is visually rich and attractive. This is because of extensive support for graphics. This was not a feature available in the DOS system.

*Multitasking in Windows *

The Windows operating system allows multitasking. Multitasking means executing several programs simultaneously in the computer. It is possible to open many programs and keep them running together by sharing CPU, memory and other computer resources. Each task opens up and runs in a separate window. One task will not interface with other tasks. For example you can db word processing, web browsing or play music or video all at the same time.

*Windows Versions *

The first fully fledged version of Windows was released in 1995. It was named Windows '95’. Later many other versions were released. These are Windows 98, Windows NT and Windows 2000. There are also some special editions of Windows suitable for laptops and note book PC's. These versions are named Windows XP, Windows CE, Windows Vista, Windows 7, Windows 8 and Windows 10. Most of these versions (Except Windows NT) had a feature known as Plug and play. Plug and play means that the system will automatically detect and configure most new hardware devices like mouse, modem, printers, sound card etc. Most people use Windows for running multimedia applications.

UNIX Operating System

The UNIX operating system was first developed at Bell Laboratories, USA in 1969. It is a multiuser time sharing system. UNIX was a major operating system for large machines. Today there are many versions of UNIX that run on a wide variety of computers from PC's to mainframes. The UNIX operating system is written in the C programming language. Therefore it was easy to modify the program to run on different hardware.

The important features of UNIX are

➢ Simple and powerful command interface called the shell

➢ Large number of tools for program developers.

➢ An easy to use file system with a tree structure.

➢ Unix offers security protection, ie, every user must he identified with user id and password. It is also possible to control access to files.

LINUX

Linux is a 'Unix like' operating system which was developed by many developers all over the world. Linux follows the free software philosophy. Many versions of Linux are supplied along with the source code. Users have the freedom to modify the operating system and redistribute it. Linux combines the powerful Unix features along with a easy to use graphical interface. It is best suited for being used for running servers. It can also be used on desk top PC's. Linux has became very advanced and a close competitor to the Windows operating system. Different distributions of Linux are Red Hat Linux, Suzze Linux etc.