Wolmer’s High School for Girls
Information Technology
Grade 10Teacher: Mrs. McCallum-Rodney
SYSTEM AND APPLICATION SOFTWARE
INTRODUCTION
In the world of computers, a distinction is made between hardware and software.
Hardware refers to the actual machinery that makes up a computer system – for example, the CPU, input and output devices, and storage devices. Software refers to computer programs. Programs are what direct the computer system to do specific tasks, just as your thoughts direct your body how to speak or move in certain ways. Computers use two basic varieties of software: application software and system software.
APPLICATION SOFTWARE vs. SYSTEM SOFTWARE
Application software is designed primarily to perform tasks such as computing bank account interest, preparing bills, creating letters and scheduling airline flights. In other words, Application Software makes possible the types of work that most people have in mind when they acquire a computer system. The largest body of application software is productivity software, which is designed to improve workers’ performance. Examples of Application software are, word processing programs, spreadsheet programs, database manager, computer games, educational software, software geared to scientific research, and programs that make gadgets such as exercise bikes and television sets work better.
System Software consists of programs operating in the background that that enable the application software to run on a computer systems’ hardware devices. One of the most important pieces of systems software is the operating system (a set of control programs that supervise the computer system’s software). Without the operating system, none of the other programs in your computer system can run.
OPERATING SYSTEM
Operating System is the main collection of programs that manage its activities.
The primary chores of operating system are management and control.
The operating system ensures that all actions requested by a user are valid and processed in an orderly fashion.
It also manages the computer system’s resources to perform those operations with efficiency and consistency.
Most tasks that you do on the computer involve some work by the operating system. For example, when you want to finish typing the letter you started typing yesterday, the operating system fetches the appropriate word processing program and document from disk and loads them into memory. It also prepares the CPU and printer.
As the word processor carries out its processing tasks, the operating system acts as a watchdog, monitoring every step of the application to make sure it doesn’t perform any illegal operations that would corrupt other computer-system resources.
Without the operating system no other program can run.
Functions of an operating system
Interacting with users – One of the principal functions is to translate user intentions into a form the computer understands. In the other direction, it translates the feedback from the hardware (such as a signal that the printer has run out of paper or the CPU is busy with a processing task) into a form that the user understands.
Making resources available – When you first turn on the computer system, the operating system boots up or is bootstrapped. During the booting procedure, parts of the operating system determines what hardware device are online, makes sure that its own files tell it how to deal with those devices, and reads an operating batch of directives.
Scheduling Resources and Jobs – Scheduling routines in the operating system determines the order in which jobs are processed on hardware devices. The operating system also schedules operations throughout the computer system so that different parts work on different portions of the same jobs at the same time. Input and output devices work much more slowly than the CPU itself, the CPU may complete billions of calculation for several programs while the contents of a single program are being printed or displayed.
Monitoring Activities – The operating system oversees activities while processing is under way. For example, the operating system terminates programs that contain errors or exceed their maximum storage allocations. In doing so, it sends an appropriate message to the user or system operator.
Housekeeping – The operating system organizes the hard disks and makes user aware of its contents. To simplify access to the hard disks, operating systems commonly organize files hierarchically into directories/folders (a collection of files grouped under a name of its own).
Security – A computer operating system can protect it against unauthorized access by collecting system-usage statistics for those in charge of the computer system and reporting any attempts to breach system security. To further ensure the security of computer systems, many operating systems contain password procedures to prevent outsiders from accessing system resources not open to them. Many also provide encryption procedures that disguise valuable program and data.
Popular operating systems
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- MacOS
- MS-DOS
- MVS, VM, OS/309
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- NetWare
- OS/2
- Penpoint
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- PC-DOS
- UNIX
- VAX/VMS
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- Windows 3.x*
- Windows 9x
- Windows NT
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APPLICATION PROGRAMS
Custom-written vs. General purpose software
Custom–written software is developed by programmers to meet the specific needs of an organization, such as a company or university. Custom-written software is expensive but sometimes an organization’s needs are so specialized that no alternative exists. An example of a custom-written software is the grade-tracking program used by a college’s registrar’s office.
General-purpose software, in contrast, is aimed at a mass market that includes home as well as business users. Although general-purpose software can be customised, it is designed to be immediately useful in a wide variety of contexts. An example of a general-purpose software is PowerPoint.
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