Software

Distinguish between the two categories of software.

Define application software Give examples of types of application

software Explain the terms

◦ General-purpose◦ Integrated◦ Specialised◦ Customised◦ Custom-written

Application Software◦ These are programs developed to carry out

specific tasks or solve particular problems.

System Software◦ Manages and supports the resources and

operations of a computer system. It enables the running of application software and management of system resources.

Examples include:◦ Entertainment software◦ Home & personal software◦ Productivity software ◦ Specialist software

Also called “off-the-shelf” Not written for any specific business or organization but can be used or adapted to suit their specific needs.◦ Usually well tested ◦ Relatively cheap

Example Spreadsheet and word-processing packages.

A set of related programs combined in a unified package that allows data to be transferred easily between the programs.◦ Main advantage is the ease with which data can

be transferred from one component to another using a cut/copy-paste operation.

Examples Microsoft Office, Microsoft Works, Sun OpenOffice, iWorks

Software written for a specific task rather than for a broad application area.

Example payroll, expert systems, accounting programs, theatre and airline booking systems

General-purpose software which has been modified to meet the needs of an individual or organization better.

Customized through the use of special codes or macros (which are short programs written to automate several steps in software)◦ Usually written by experienced end users of the

program.

Written by programmers within a company or contracted out to a software house to meet the specific needs of a company.

Every company is unique and may have unique needs, so a solution tailored to achieve the company’s goals, based on their specialized requirements offers advantages when compared to general-purpose packages.

There are two major categories of system software:

Operating System Utility programs

One textbook has a third… Language translators

A set of programs managing the operations of a computer, without which the computer cannot function. ◦ the term ‘booting’ refers to the process of loading

the operating system into a computer’s main memory from disk. It remains in the main memory until the computer is turned off.

Linux Microsoft Windows MSDOS OSX OS/2

Microsoft NT Server Unix

Managing computer resources Managing files and memory Maintaining security Managing tasks

◦ Multitasking (concurrent processes – running at the same time)

◦ Multiprogramming Multiprocessing

◦ Time-sharing◦ Batch Processing◦ Real-time processing

Providing a user interface

Command-driven◦ User enters a command by typing in codes or words.

Menu-driven◦ Allows the use of either a mouse, cursor-keys or

keyboard to make a selection from a menu. Graphical (GUI or WIMP)

◦ Windows◦ Icons◦ Menus◦ Pointers◦ Use graphic images, menus and keystrokes to choose

commands, start programs, folders, files, tasks, procedures .