SOFTWARE

Application Software System Software

Types of Software

Performs specific tasks and works on top of the operating system.

Three main types◦ General Purpose◦ Special Purpose◦ Custom Written

Application Software

OPERATING SYSTEM

APPLICATION SOFTWARE

Software that performs basic tasks that most users would need to do. Comes in a software suite or Integrated software.

Eg. Microsoft Office, PDF reader, Adobe Photoshop

General Purpose

ADVANTAGES DISADVANTAGES

Relatively Cheap Little or no Customization

Easy to learn Comes in a package and cannot be separated

No compatibility issues

Easy to Install

Software designed to perform a specific task.

Eg. Accounting, Engineering Design, Music player.

Special Purpose

ADVANTAGES DISADVANTAGES

Meets a specific need Can be expensive

Usually integrates with other software well

Has no other use other than what it was made for.

Software that is designed specifically for an organization to meet their individual needs.

Eg. Government databases, Large businesses.

Custom Written Software

ADVANTAGES DISADVANTAGES

Meets the individual needs of the user

Very costly

Can be modified to meet new needs

Difficult to troubleshoot at times

Cannot be used for anything else.

System software

They enable the computer to run properly. Application programs depend on the System software to run.

There are 2 main types OS (Operating System) Utilities

System Software

The operating system is the set of programs that controls all the hardware and application programs that make up the computer system.

They are the most important programs because every other program depends on it.

Eg. ◦ PC-Windows, Linux, UNIX, Mac OS, DOS◦ Phone -Android, iOS, Symbian, Windows Mobile

Operating Systems (OS)

Process Management◦ Allotting adequate time and resources to each

process/program File Management

◦ Provides the ability to modify files and folders while keeping track of their physical location on the hard drive.

Memory Management◦ Manages the memory the computer has so that

every program can get to load as quickly and efficiently as possible.

The OS does many functions

Input/Output Management◦ Controls the communication with external

hardware like keyboard, mouse, printers, monitor etc…

Security and Maintenance◦ Provides some level of security to ensure the

software is safe from viruses and malware. Provides utilities to ensure backups and error corrections take place.

User Interface◦ Provides a user interface that the user can

interact with to give inputs.

OS functions contd…

USER INTERFACES

THREE TYPES Command Line Menu Driven Graphical User Interface (GUI)

User Interfaces

A user interface that requires the user to put in special commands line by line to do tasks.

Eg. MS-DOS, UNIX DISADVANTAGES

◦ Requires knowledge of the commands ADVANTAGES

◦ Tasks can be executed very quickly once the commands are known.

Command Driven Interface

Interface where the user can select multiple commands from one or more menus

Eg. Turbo Pascal DISADVANTAGES

◦ A lot of options may lead to confusion◦ Some options may not be available

ADVANTAGES◦ User does not have to remember commands

Menu Driven Interface

Interface where images are used to represent the choices a user can make.

Eg. Windows, Linux, MacOS, iOS, Android

ADVANTAGES◦ Easy to understand and learn

DISADVANTAGES◦ Some tasks can take long because there are

many menus to go through to get to one choice

Graphical User Interface (GUI)

MULTITASKING The execution of two tasks at the same time.

MULTIPROCESSING The use of 2 or more CPU’s to execute

different tasks simultaneously

MULTIPROGRAMMING When two or more programs run on the

same processor working one after the other.

Multitasking, Multiprocessing, Multiprogramming

PROCESSING

TYPES OF PROCESSING Batch Processing Online Processing Real Time Processing

Processing

When Data is collected and stored for a period of time and processed after.

Also known as offline processing.

Eg. Salaries in a company, Printing documents, Birth Certificates

Batch Processing

When data is collected and processed immediately and cannot be changed.

Eg. ATM Machines, Flight Bookings, Online reservations

Online Processing

When data is input processed and output continuously. Activities are constantly happening.

Eg. Real time flight bookings, Facebook feeds, Checking criminal records

Real-time processing

TYPE OF PROCESSING

ADVANTAGES DISADVANTAGES

BATCH • Saves on time in the long run

• Changes cannot be made easily once batch has not been run.

ONLINE • Takes information and processes it on demand

• Changes are not made as quickly

REAL-TIME • Changes are made instantly

• Requires high processing power

Comparison Table