Computer Software

Computer software is set instructions that instruct the computer on what to do and how to do it. Computer software

is also called programs. Unlike computer hardware, computer software cannot be seen and cannot be touched.

Computer software is categorized into two:-

1) System software

2) Application software

System software

It is a type of software that controls the general working of the computer. System software consists of programs that

control the operations of a computer and its devices. System software serves as the interface between a user, the

application software, and the computers hardware. Before application software can be run, the operating system,,

must be loaded from the hard disk into the computers memory. The two main examples of system software are

Operating System (OS) and utility programs.

Operating System

-It is a set of programs that controls how the application software interacts with the computer hardware. It enables

the application software to use the computer hardware and other resources.

It is software that controls the general operation of a computer.

Functions/roles of an operating system

The OS has many functions including the following:

1. Input and output control

2. Error handling

3. Resource allocation

4. Providing a Human Computer Interface.

5. File handling.

6. Managing the computer system security

7. Interrupt handling.

8. Job scheduling.

Functions/roles of an operating system

1) Input and output control -

The OS controls all input and output and the transfer of data within the computer to ensure proper functioning

of application software.

2) Error handling

The OS manages all errors that occur while the computer is working by displaying an error message so that the

user can correct the error. E.g. when printer is out of paper.

3) Resource allocation

It ensures that all processes have access to the different resources they need for smooth running. Allocates

memory space and CPU time for programs and data. It keeps track of parts of the memory that have already

been allocated and those that are free.

4) Providing a Human Computer Interface

The OS provides a way of interaction/communication between the computer& the user. It enables a user to

issue commands to the computer and display responses from the computer in a way that the user understands.

5) File handling.

The OS handles all files stored on the computer allowing the user to name them, save, edit, copy delete e.t.c.

6) Managing the computer system security.

Monitors and restricts access to data &programs in the computer. It prevents unauthorized access to the system.

7) Interrupt handling.

Handles interrupt signals whenever they occur while using the computer. Interrupts are signals sent to the

computer to enable it perform tasks.

8) Job scheduling.

The OS arranges the tasks being performed by the computer so that they can be performed in the right order.

Utility programs

These are programs that perform routine tasks that help the user to maintain the computer making other

application software to run better. To carry out routine tasks that is often needed by the user

Functions of utility software

1) compressing a file to save space on backing storage

2) Defragmenting a disk drive

3) Recovering data from damaged file

4) Checking a disk for faults and recovering them

5) Formatting a storage disk.

6) Checking the files on a dish for computer viruses - checking a dish for faults and recovering them.

APPLICATION SOFTWARE

Application software consists of programs designed to enable the user to perform specific tasks. It is software

designed to do a specific task or job.

a) Custom designed / tailor made/ in-house software

Is a type of software designed to save a specific problem within a specific organization

Advantages

1.) It is a designed to solve the problem it was meant for exactly

Disadvantages

1.) It is an expensive type of application software.

2.) Doesnt come with health instructions.

Application specific software

Is application software used to solve a specific problem that is common in different organizations?

Examples

Stock control software

payrou software

Advantages

1.) It can be used in more than 1 organization

2.) The program is well tested and document

Disadvantages

Is only meant to solve specific tasks

General purpose application software

Is an application software used to save more than 1 task. Examples include:

i.) Word processors

ii.) Desktop publishers

iii.) Databases

iv.) Spread sheets

v.) Graphics software

vi.) Presentation software

vii.) Web authoring software

viii.) Project management software

ix.) Control software

x.) Integrated software

Word processors

These are programs used for preparing documents. Examples of documents include letters, summary reports and

memos?

Features of Word processors

1) Has text formatting tools such as underlining, bolding, italics etc

2) Has spell checking and grammar checking tools

3) Has a verity of font faces

4) Has facilities for printing and addressing a set of letters

5) Has templates that control the layout of documents e.g. changing magazines, pg numbering etc

Application of Word Processors

1) Writing letters/ summary reports and other documents an office

2) For producing of articles issued letters-producing

3) For producing personal used letters a set of similar letters to be posted to a number of people

Examples

i.) Microsoft Word

ii.) Word perfect

iii.) Word star

iv.) Wang Writer

DESKTOP PUBLISHER (PTP)

CHARACT RISTICS

1) HAS THE FACALITIES to divide a document into pages and the pages might be divided into colors

2) Has good word processing civility a verity of fonts

3) Has facility for importing pictures and drawing files from other application

4) Has good facilities for arranging reset pictures

APPLICATION

1) to produce noels papers/ newsletters and magazines

2) to produce posters , to add picks, logos etc to let us to make attractive

DATABASES

Is a program for handling a tile and retrieved information?

For them

CHARACTRESTICS

1) Data is stored in the form to record is a collection of related fields

2) Has facilities for information retrieval i.e. producing lists of cell record that need certain conditions

4) Has the fasciitis to combine results into reports

APPLICATIONS

1) Main ting personal lists such as details of customers / addresses and accounts

2) Allowing access to a large stones at information such as encyclopedia on a cd rom

EXAMPLES OF DATA BASES

1)Microsoft access

2) Oracle

3) Fox pro

4) Open office databases

5) D base ii plus

SPREAD SHEET

Is a program which displays information in form of a table. The table is divided into rows and color of individuals

and boxes known as cells the spread sheet program allows calculations to be done on cell or in group of cells.

CHARACTERISTICS OF SPREAD SHEET

1) Has the feature that allows the user to enter text, numbers of a formula into any cells

2) Formula and other data can be copied into groups of cells

3) Has formulas that allows calculations to be done on other cells

4) Allows a Varity of operations to be done on rows and column e.g. :-resign rows and column inserting and deleting

rows and columns

APPLICATIONS

1) Displaying and calculating accounts and other financial information

2) Performing calculations on data collected in experiments and surveys.

3). Producing columns of data from which graphs can be drawn

EXAMPLES OF SPREADSHEET PROGRAMS

1). Microsoft excel

2).lotus 1-2-3.

3).Quadra pro.

4). Open office spreadsheet.

GRAPHICS PACKAGES (SOFTWARE).

Is a general purpose application software used to produce graphics e.g. graphs and charts, drawings painted images.

FEATURES/ CHARATERISTICS OF GRAPICHS PACKAGE.

1). Has tools for drawing e.g.: pens, paint brushes etc.

2). has a color palette to enable the user to select different colors.

30. Has asset of predefined shapes.

4). has facilities to import and export graphics.

5).has tools to edit pictures or drawings.

6).has a tool for arranging objects in different lay us.

7).has a 200m tool for enlarging part of an image.

8 )has a facility to group or ungroup an object.

9 )Has a

tool for erasing (rubbing) out parts of a picture.

10) Has a tool for rotating objects

Types of graphic packages painting packages

Are graphic software that produce images by changing the color of pixals on the screen images are produced by

painting packages are called bit mapped graphics.

Advantages of bit mapped graphics.

Individual pixels can be changed which makes very detailed editing.

Disadvantages of bit mapped graphics

1) They take up a lot of memory space.

2) The quality of the image is affected when its size is enlarged or reduced.

3) Individual parts of an image can be resized.

Examples of painting packages

Ms Paint

Application of painting and drawing programs

1) For drawing on the screen

2) For producing simple illustrations for instant front cover of the school projects.

Images produced by drawing packages

-images produced by drawing packages are known as vector format images/graphics.

-vector format images/graphics are represented by mathematical codes.

Advantages of vector format files

-they dont take a lot of memory space

-the quality of the image is not affected when its size is changed

-allows part of the to be resized.

Disadvantages of vector format files

-hard to make detailed editing

Examples of drawing packages

1) CAD (computer aided design)

2 )ARCHICAD

Application of drawing packages/ CAD package

-in architecture for producing designs of buildings

-in engineering drawings

Differences between vector format files images& bit mapped files/images

Bit mapped files/ images Vector format files /images

Is produced by painting packages Is produced by drawing packages

Quality of the image is affected (lowered) when the

size of the image is resized

Quality of the image isnt affected when the image is

resized

Take up a lot of memory space as compared to vector

format files

Take up less storage space as compared to bitmapped

file format

Produced by changing the color of pixels Are represented by mathematical codes

Hardware requirements for drawing packages (CAD)

1. The computer should have a large RAM

2 .the computer must have a graphics card

3. The computer monitor should have high resolution screen

4. The size of the monitor /display screen should be large

5. The computer should have a plotter to be used to output-the hard copy of the drawing

6) The computer should have a high /faster processing speed.

Presentation software

Is a type of software that is used for creating present anion(information)that has to be personated to the

audio

Features for a presentation software

1) has slides where information to be represented is created

2) has designed templates that can allow the user to create the presentation without formatting the back

grounds and lay out of the page

Advantages of using templates

1) they have a attractive background that attracts the eyes of the audience

2) most of them have preset layouts hence the user finds it easy to format the presentation created

3) they provide the present format of how the presentation should work like

4) provides a range of slide layouts that you can use

5) has slide transition that provides movement promote slideshow to another

6) allows sound to be in cooperated in the presentation created

7) provides animination feature that controls the way text is displayed during presentation

8) has text formatting tools that allows the user to format the document to make it attractive

9) has a slide show features that allow the user to set up the number of slides to be presented to the

audience

10) has the printing feature that comes printing of uniformities found on slides

Application of presentation software

Advertising of sales where some people create information about their product on slides and project

this information on a large screen

1) in semidries for training on how to do specific task

2) in presentation of project work

3) used as teaching aid

4) has a per line feature that allows the user to link image in another application

Examples of presentation software.

Microsoft power point.

Project management software.

Is type of software that organizes project in charecteristic and port folios and sub divided the major task into sub

task

Features.

1) Resource management features like resource port frail that organizes resource in hierarchies and port folio

which reflect company.

2) Has calendars feature that specifies the data when the event starts when its ends.

3) Has planning and scheduling task validation, automatic snapshoot and project and resource auction.

4) Has output and analysis feature like output giant.

5) Has program management feature like particular that enable the user to see the history of his successive.

6) Has the importation feature that allows, the user to important feature project, task dependencies, resources,

calendar and allocation from one of several ms project files.

Examples

Microsoft office project management software

Application

1) Designed project plans

.

Web authoring software

-is a type of software that enables the user to develop a website.

-is a web site development system that allows web pages to be visually created like desktop publishing

program.

Examples

A) Micro media dream /weaver

b) Microsoft from page.

C) Html (hyper text market language)

Features.

1) Has facilities that allow text and pictures to the imported.

2) Has tools to create and menu plate tables to petition objects like text and graphics.

3) Has tools to create hyperlink from text or and graphics

-Hyperlink- is a piece of text or graphics that link the user to the specific webpage

4) Has links to create hot spots over parts of pictures

Hotspot- is a small area of a picture or a graphic that links to specific web page

5) Provides multiple view of webpage you are working on e.g. standard or normal design view

Application of web authoring software

Used for designing website

AUDIO, VIDEO EDITING SOFTWARE

It is a software that makes it easy to join, trim and modifying audio and edit the audio and video

separately.

Features of audio video editing software.

1.) Has the crop tool for cropping the image.

2.) Has the feature for loading of multiple video and audio clips for editing

3.) Has the features for splitting and joining audio and video clip

4.) Has the feature for converting video and audio files between format

5.) Has a feature for full cross interrogation audio and video and control of volume and video

brightness

Examples of audio video editing software

1.) Cyber link power director

2.) Corel video studio

3.) Sony Vegas moving studio platinum

4.) Raxio creator

5.) Nero

Applications

1.) Used in audio and video editing

2.) Used for preparation of video clip or video film

Control software

Is a software that controls the action of movement of a the object

Examples

CTT

S P C software

Features of a control software

1.) Work independently without being controlled by a human being

2.) Can be able to repeat the action over and over again

3.) Is capable in communicating with sensors and actuators

4.) It is able to accepts more than one input at the same time

5.) It is capable of being used in dangerous awkward environment where the life of peoples can be in

danger e.g. in nuclear reactor, volcanoes

Application

1.) Washing machine

2.) Microwave cooker

3.) Dish washer

4.) Electric kettle

5.) Video recorder

6.) Fridge

7.) Remote control television

8.) Control heating system

9.) Bugler alarm system

10.) Air conditioning system

11.) Lifts

12.) Automatic dotes

13.) Factory robots

14.) Traffic light system

15.) Car park barriers etc

Integrated software

Is an application software that consists of several general purpose program which can use the same

data .

Features of integrated software

1.) It includes a word processer, a spread sheet, a data base, graphic and desktop publisher

usually

2.) The program come together in one package

3.) Data produced in one program can be easily transferred for use in another program

4.) Menus ,icons and other features are similar to each program

5.) The individual program may not be quite as powerful as separate programs to do the things

Applications

1.) To produce report which consists of a well presented document that includes list facts and

finger and graph

Used in situations where a spread sheet, database or graph are used but not often enough to justify. The expense of

buying separate package.

EXAMPLES OF INTERGRATED SOFT WARE

1) Microsoft office

2) Open office

3) Lotus suite

REVISION

1) processing hard ware

CPU -alu

2) control unit

3) Ram

4) Rom

ALU (ARITHMETIC LOGIC UNIT)FUNCTIONS

1) To perform logical Booleans function

2) To perform mathematical calculations

CONTROL UNIT (FUNCTIONS)

1) controls the flow of instructions

2) fetches decides and executes instructions

RAM FUNCTIONS

Stores screen

HUMAN COMPUTER INTERFACE

An interface is an interaction between the computer and the user .

- is a method through which the user communicates with the computer

TYPES OF INTER FACES

1) Command line driven

2) Menu driven inter face

3) Graphical user inter face

COMMAND LINE INTERFACE

Is a type of interface that allows the user to, interact with the computer typing in commands

E.g. C: 17cdwindows

ADVANTAGES OF COMMAND LINE INTERFACE

1) Fast in execution

2) Does not require a computer with a large ram or memory

DISADVANTAGES

1) requires the knowledge of commands

2) it is prom to syntax/typing errors

3) it is not good interface for novice

MENU DRIVEN INTERFACE

It is a type of interface that allows the user to choose options from the list

MAIN MENU

1) load program

2) back up files

3) exit

ADVANTAGES

1) easy to use

2) it does not need knowledge of commands

3) go interface for novice

Disadvantages

1.) has to go through a series of steps before reading the required options

2.) not fast execution

Graphical user interface (gui)

it is a type of interface that allows the user to interact with the computer by the use of icons ,pointer ,menus,

Features

1.) Has an icon, which is small pictures of graphic that represent program files folder and data base.

2.) Has pointer e.g. mouse cursor that is used for selection of options or icons

3.) Has dropped down menus that allow the user to choose options

4.) Has windows which are rectangular boxes that display information

My document recycle bin

my computer

Advantages

Doesnt require the knowledge of commands

Good interface for no voice

It is not pron to syntax/typing errors

It is a user friendly

Disadvantages

Require a computer with large RAM memory

Slow in execution

Uses of ict system

Simulation and modeling

Simulation is the use of computer system to predict the outcome of real situation by using a model of that situation

Is the creation of a model of areal system tin order to study the behavior of the system

Is a program that models the real system

Is a special type of computer model which recreates a real system from outside the computer

Examples of simulations

1.) A flight simulator that is used for training pilots