Purpose of Operating System

BTEC ND IT Practitioners Computer Systems

THE PURPOSE FEATURES AND FUNCTIONS

OF OPERATING SYSTEMS

INTRODUCTION TO OPERATING SYSTEMS

An Operating System or an OS is a program designed to run other programs and applications on a computer. It is the main program which manages other software and hardware, it is considered as the backbone of a computer. The OS acts as the hosts for applications that run on the computer. The shown diagram copied from Wikipedia explains the position of an operating system in a computer structure.

There are mainly five types of operating systems- Multiuser, Multiprocessing, Multitasking, Multireading and Real-time operating systems. A Multiuser OS enables multiple users to use it at the same time. A Multiprocessing OS run programs on more than one CPU at a time. Multitasking OS enable users to run more than one program at a time. Multireading system allows various parts of one program to use at the same time. A Real-time OS makes it possible for the computer to respond to inputs instantly. Most of the operating system comes under one or more of these types.

All computer devices like videogame consoles, desktop computers, supercomputers and smart phones consist of operating systems of some sorts.

An Operating System generally performs these services:-

Manages the sharing of internal memory to multiple applications.
Manages inputs and outputs to and from hardware devices.
It sends messages to specific applications and the user about the system status and any occurred error.
It controls the management of data send to hardware by an application, for example printing data send to a printer.
It manages how to divide the programs to run in processors.
In a multitasking computer the OS decides which application should run in what order.

THE FEATURES OF AN OPERATING SYSTEM

User Interface

The user interface of an Operating System controls what the user sees. The user interface accepts the input from the user, interprets the command and then takes appropriate action. For example the user interface manages the opening and closing of a window, the loading of applications and software etc.

Multi-tasking

This interface copes with the user running more than one application at the same time. For example when using clipboard if the user closes an application leaving a large amount of data on the clipboard the operating system will remind the user if the data needs to be used in another application.

Data Movements to and from all Peripherals

The operating system accepts requests for data from applications and sends messages on-screen to the user. It gives error message if the disk drive is open or if the printer has run out of paper or ink.

The Peripheral Management

The ...

This is a preview of the whole essay

Data Movements to and from all Peripherals

The Peripheral Management

The peripheral management of an operating system sends output to a printer. It uses temporary disc files to save the data that is building up from each application. It deletes the temporary files once they were send to its destination. If for example data is send to the printer from one application when the printer is busy printing from another application the peripheral management of an OS keeps the second data on the temporary memory and waits for the first printing data to be finished.

OPERATING SYSTEM COMPARISONS- WINDOWS & LINUX

Linux is an open source OS software initially developed by a university student in Finland as a hobby. As its Open Source its code is available to everyone freely. Linux’s functionality and adaptability made it an affordable alternative to expensive Microsoft Operating Systems. This result in the growth of the use of the Linux as operating systems in home and office desktops. Linux comes with everything we need to carry out our day-to-day tasks on computer. An important characteristic of Linux is that it can be used live from a bootable device without an installation. Linux is not a single program, together with a set of programs makes it an OS. There are many versions of Linux known as ‘Distributions’.

Microsoft Windows are OS’s and graphical user interfaces developed and distributed by Microsoft Corporations. This is first released as an Operating environment in the month of November 1985 as the successor to MS DOS as a result of the growing interest in Graphical User Interface. Like Linux Windows also have a lot of versions. The latest version of Windows is Windows Vista.

Below is the screenshots of two versions of Windows – The Windows Workgroup (figure 1) released in 1993 and the Windows Vista Ultimate (figure 2) released in 2007.

Windows and Linux come with different versions. All of the windows versions come from Microsoft Corporations while Linux is modified and distributed by different companies. They include Redhat, Ubuntu, Linspire, Suse, Knopix etc. Windows have mainly two flavours- the Win9x and the NT Class. The Win9x consists of older versions like Windows 95, Windows 98 etc. The NT Class consists of Windows 2000, Windows XP and Windows Vista. There are too many versions of Linux, this is because that it is more customizable in a way that Windows cannot be. The Linux’s user interface varies from distributions to distributions. The ultra small edition of Linux is capable of networking, file sharing and to be a web-server, none of these are possible in Windows.

Both Windows and Linux provide GUI and a command line interface. There is a lot of change in the user interface from Windows 3.1 to XP and to Windows Vista. Linux mainly provide two GUI’s – the KDE and the GNOME. The Windows and the .NET Magazines in March 2000 said that the Linux GUI is optional and the Windows GUI is one of the main components of the operating system. The magazines explained that a Linux shows an improvement in the speed, efficiency and reliability without its GUI. It is something that Windows OS cannot dream about. This flexibility of Linux GUI is considered as a good thing which allows experienced and expert users to customise it to their needs. But it makes things harder for new users as they try different versions of Linux.

In Windows the Command Line Interface is known as DOS prompt. In Linux it is known as a shell. The command prompts in Windows9x series are similar to each other and in NT class versions have similar interface. Like all Unix versions Linux supports multiple Command Line Interfaces usually known as BASH.

The cost is the main difference between a Windows OS and a Linux one. Linux is free or cheap to use in desktops while Windows are really expensive. Microsoft allows a copy of Windows to be used in only one computer, now the company uses software to make sure no illegal copies are used. While in the case of Linux once purchased or downloaded there is no restriction to run the same copy in as many computers. Linux even encourage users to pass it on to others. The Computer World Magazine in October 2002 states that the cost of running Linux is a tenth the cost of Microsoft alternatives.

Installing the OS

There is mainly three ways to install the new versions of Windows- a clean install, an upgrade install and repair install. A clean install means installing the OS to an empty machine. An upgrade install is the process of upgrading an older version of Windows with a newer version. A repair install refers to install a version on top of the same one; this kind of installation is common because of registry errors or missing system files. The Linux installation defer far from the Windows installation. Different versions of Linux have different installation procedures. It even changes with the different versions of the same distributions. When installing Linux on a machine where we don’t need to keep the existing operating system there used to be an option to criticise or to wipe away the existing ones. Installing Linux keeping the existing OS is best to leave for the experts as it is too easy to lose the existing operating system and data. For these procedures the user should be an expert in Linux and hard disk partitions. The Windows Vista makes even a little user an expert in disk partitioning.

Linux can run from a CD while Windows cannot. To run a Windows OS it needs to be installed on the machines hard drive, Linux can also run installed from a hard drive. In some cases software are available to run from CD for Windows, which can be used only if it persist any start up problems. This is not for everyday use and importantly it is not from Microsoft.

Applications and Software is something which we need for our common computer use. With a purchased copy of Microsoft Windows no major software is available. But on the other hand with a copy of Linux we get a lot of free application software. But again the installation of extra applications in a Linux machine is not as easy as of Windows.

As we know all software has bug related problems. Linux is said to have fewer bugs compared to Windows. The Information Week magazine in Jan 2003 stated that bugs related to Linux is fixed in a better and faster way by the experts and the public while Windows takes ages to solve its bugs as it cannot be altered by the public and is in the hands of Microsoft Programmers. In March 2003 Microsoft declared that it will not publish the solution for a Windows NT4 bug as it will cause security issues for Windows 2000, XP and NT4. It is said that this is a trick by Microsoft to flow the users into new versions of Windows. These rumours will not happen in an open source software like Linux and its not possible to say that a bug cannot be fixed for a version of Linux.

The difference in operating systems development says that Linux is more stable. Windows is developed by Microsoft employees whose mistakes are hidden from the world outside as the company do not publish codes to review or update for those interested. On the other hand codes are available for Linux which can be reviewed and updated by anyone.

Linux is able to run on almost all hardware platforms. Because of its ability to run without a GUI it needs less processing power than of Windows. And because of this reason Linux can run on very old computers and make it useful. Linux provide a multiuser licence where Windows do not. Windows is designed to be used in a single computer at a time. The Windows OS is designed to manage a single user at a time while Linux is designed to handle multiple users at the same time. Both and Windows and Linux can run multiple programs at the same time.

In the case of hard ware partition Windows can be installed and boot from only a primary partition. A Linux can be installed and boot from either from a primary or a logic partition. So as many versions of Linux can be installed according to the number of disk partitions and we can experiment many Linux at the same time.

Martin Ultima, the person related to the Ultima Linux distribution stated that he do not see a future for Linux in desktop computers. His main reasons are: Video drivers are hard to set up, poor support for Wi-Fi, painful software development, problem with printer and other hardware connections, poor OS documentations etc.

I personally recommend using Windows as I do not have any previous experience with any versions of Linux. The below chart shows the OS market share till May 2008. It says 91% of OS in use is Windows and Linux comes only by 4.7%. How could 91.1% of Windows users go wrong?