Dr. J. VijiPriya Information and Communication Technology Chapter 5,6

Information and Information and Communication Communication TechnologyTechnology

Chapter 5- Computer SoftwareChapter 6- Computer Care and Safety

9/12/2015

Dr. J. VijiPriya, Assistant Professor, Hawassa University, Ethiopia 1


Chapter 5- Computer Software

9/12/2015


Introduction to Computer Introduction to Computer SoftwareSoftware Computer

◦ can not think or perform on its own, ◦ But it performs various operations only in accordance

with the user instructions. Instructions

◦ written in a language ( called program) , understood by a computer

◦ controls the sequence of operations Program

◦ Set of instructions, controls the processing activity of computers

Software ◦ Set of programs, procedures and associated documents

Set of Instructions->Programs-> Computer Software

9/12/2015


Relationship between Relationship between Software and HardwareSoftware and Hardware

Hardware (visible devices) assembled together to build a computer system

Software loaded (set of programs) into a computer system

Both software and hardware gives life to a computer system

Both are complementary to each other

9/12/2015


Software Categories Software Categories

9/12/2015


Computer software

System software

Application Software

System management

System development

High level programming

language

Utilities Device driver

Low level programming

languageOperating

system

Software Categories Con…Software Categories Con… Two major categories

1. Application software.2. System software

TypesI. System Management

Operating System Device Driver Utilities

II. System development Assembly Language High Level Language Low Level Language

9/12/2015


System Software System Software ◦ essential for computer to function. ◦ helps the computer manage its own tasks and devices. ◦ designed to control the operations and processing

capabilities of a computer system◦ provides user interface◦ monitors the effective use of various hardware resources

such as CPU, memory, peripherals etc.◦ support the development and execution of other

application software◦ permits the user to use the system more conveniently. ◦ Example :

i. Operating Systemii. Device Driveriii. Utilitiesiv. System development programs

9/12/2015


Operating System Operating System Operating System (OS)

◦ set of programs control the resources of a computer system ◦ provides its users with an interface◦ basic functions of OS

i. Process Managementii. Memory Managementiii. File Managementiv. Device Managementv. Security Managementvi. User Interface

9/12/2015


Operating System Con…Operating System Con…Basic functions of OS Process Management:

handles the creation, deletion, suspension, resumption, scheduling and synchronization of processes.

Memory Management: handles allocation and de-allocation of memory space as required by various programs.

File Management:responsible for creation and deletion of files and directories. organizes, stores, retrieves, names and protects all the files.

Device Management: manages all the devices of the computer system such as monitor, printer, disk etc.

Security Management: protects system resources and information against destruction and unauthorized use

User Interface: provides the interface between the user and the hardware.

9/12/2015


Device DriversDevice Drivers New device driver must be installed before the device can be used

in the computer

Most hardware drivers such as keyboard driver, comes with the operating system in the modern computer

For other devices like printer, a user must load the device driver of that particular device

9/12/2015


System UtilitiesSystem Utilities Set of programs that help users in system

maintenance tasks and in performing tasks of routine nature.

Example◦ Formatting hard disks or floppy disks.◦ Reorganizing files on hard disk to conserve

storage space.◦ Taking back up of files stored on hard disk◦ Checking the amount of available memory

and storage space on hard disk.◦ Scanning the system for computer viruses.

9/12/2015


System Development System Development ProgramsPrograms allow programmers to write and construct programs that the

operating system can execute Examples

◦ Computer programming languages◦ Language translators◦ Linkers◦ Loaders

Computer Programming language series of commands /instructions are used in development of

software divided into three categories namely,

i. Machine language ii. Assembly language iii. High level language

9/12/2015


System Development System Development Programs Con…Programs Con…Language Translator Machine Language

◦ Computers only understand this language consisting of only 0s and 1s

High level programming languages◦ natural languages like English

Language translator◦ converting programming language to machine language. ◦ three types of Language translator

i. Assemblerii. Compileriii. Interpreter

9/12/2015


System Development System Development Programs con…Programs con… Three types of Language translatori. Assemblers◦ translate assembly language programs into machine code

executed on the target computer.ii. Compilers◦ reads the source program (high level language programs)

statement by statement, translates it into an equivalent machine code

◦ produces the object program file, then executed without the presence of the compiler

iii. Interpreters◦ reads one statement of the source program, translates it and

executes it immediately. then goes to the next statement ◦ doesn’t produce an executable object program file.

9/12/2015


System Development Programs System Development Programs con…con…Linker links several object modules and libraries to form a single, coherent

program (executable) Loader loading and relocation of the executable program in the main

memory assigning storage allocation, assist a program, and execute it

properly

9/12/2015


Application SoftwareApplication Software accomplish specific tasks rather than managing a computer system a single program

Eg:- Microsoft’s Notepad a collection of programs called a software package,

Eg:- Spreadsheet package. a larger collection of programs ( a software suite), related but

independent programs, which have a common user interfaceEg:-Microsoft Office Suite.

are controlled by system software application layer executes on the system software layer,

which lies on the hardware layer.

9/12/2015


Application Software Con…Application Software Con…

9/12/2015


Application Software Con…Application Software Con…Word Processor computerized typewriter, permits the electronic creation, editing

formatting, filing and printing of text, then correct them a common application of microcomputers draft and revise memos, letters, reports, and other documents with

a word processing program more frequently increases both the speed and quality of writing express ideas more clearly

Eg:- MS Word, WordPerfect etc.

9/12/2015


Application Software Con…Application Software Con…Spreadsheet electronic worksheet displayed on the VDU. Used for accounting, financial analysis, and other mathematical

calculations quickly create a model of a situation byy entering labels, numbers,

and formulas Details are entered into the computer and recorded in predesigned

rows and columns to form a grid of cells for performing specific computationssuch as net present value, internal rates of return, and monthly payments on a loan

save a spreadsheet model and use it again whenever you need it Eg:- Microsoft Excel, Lotus 1-2-3 etc.

9/12/2015


Application Software Con…Application Software Con… Database Management System

◦ Used to create a database, maintain it( add, delete and update its records),

◦ organize its data in desired fashion and to selectively retrieve useful information from it.

◦ Used for both large and small organizations to maintain employee data, customer data, asset data, accounting data etc.

◦ Eg:- dBase III Plus, FoxPro, MS Access, Oracle etc.

9/12/2015


Application Software Con…Application Software Con… Computer Graphic Software

◦ technique of creating, editing, displaying, and printing graphs, diagrams, charts, and images in the computer

◦ a picture is worth a thousand words applies to computer graphics ◦ convey information that could be difficult or even impossible to

put into words.

9/12/2015



Chapter 6- Computer Care and Safety

9/12/2015


Computer Care and SafetyComputer Care and Safety1. Keeping your system free of dust, dirt and liquids2. use system's user guide to find information on how to

clean your outer components◦ Never spray your monitor screen (or any other computer

component) with glass cleaner◦ Computer components should be kept as dust-free as possible. ◦ Use Canned air or small computer-specific vacuum cleaners ◦ The mouse does not perform correctly, check your user guide for

cleaning directions. ◦ Never try to remove the cover on your computer to clean inside.

Instead, take it to a technician◦ Keep all liquids and food items away from your computer,

because cause damage delicate electronic circuits and serious electrical shock!

◦ Wash your hands before using the computer to avoid "sticky keys."

◦ When in doubt about how to clean your computer system, consult your user manual or technical support

9/12/2015


Computer Care and SafetyComputer Care and Safety3. Never use your computer during a storm.4. Protect your computer from viruses and worms.

◦ Install, use and regularly update virus software ◦ Never open an email attachment unless you know and trust the

person who sent it. ◦ Do not accept downloads from Internet sites that you don't know

and trust. 5. Avoid installing several programs one right after the

other; try installing one program, see how your system responds to the installation before loading the next program

6. Keep CDs away from dust, liquids, or other damaging or corrosive substances.

◦ If problems with CDs, buy a CD cleaner and read the instructions carefully

9/12/2015


Engineering

Dr. J. VijiPriya Information and Communication Technology Chapter 5,6