Introduction to computer

Why to Study Computer?

Skills that span different aspects of life

Easy Access to information

Greater Self Efficiency and Sufficiency

Improved Employment Prospect

Introduction to

Computer

CRT Display

Keyboard

Mouse

CasingCD-ROM Drive

FloppyDiskDrive

USB Port

University of RajshahiDept. of Computer

Science & Engineering

Computer - the word• The first use of the word “computer” was recorded in 1613 in a

book called “The yong mans gleanings” by English writer Richard.

• The writer used the word computer to refer a person who carried out calculations, or computations, and the word continued with the same meaning until the middle of the 20th century.

• From the end of the 19th century the word began to take on its more familiar meaning, a machine that carries out computations.

What is Computer?• A computer is an electronic device that can receive data as

input, process the received data and convert it into meaningful information as output, which is useful to people.

• It has the ability to store, retrieve, and process data.• Charles Babbage is Considered as the father of the computer.

Babbage is credited for inventing the first mechanical computer.

• ENIAC(Electronic Numerical Integrator And Computer) was the first electronic general-purpose computer. It was digital and capable of being reprogrammed to solve a full range of computing problems.

Charles Babbage (26 December 1791 – 18 October 1871)An English man known for mathematics and computer science

ENIAC was initially designed to calculate artillery firing tables for the United States Army.

It was then announced as “Giant brain”

What is Computer? It performs the following four actions:

1. Receive Input

2. Processing

3. Produce Output

4. Store The above four operations together is called information

processing cycle

Information-processing cycle

PROCESSING OUTPUT

STORAGE

INPUT

Definitions Input: User gives instruction to the computer in the form of

input. Devices that enable the user to enter data into the computer for processing are called input device. In other words device that is used to give input is called input device. Examples: mouse and keyboard

Processing: converts input into output Output: Computer provides the results of the processed

instruction or operation in the form of output that people can understand easily. Devices that enable the user to receive information from the computer after processing called output device. In other words device that is used to give output is called output device. Examples: monitor and printer

Storage: Computer saves the processed result into the storage to use again later for both the user and the computer. Storage devices hold all of the programs, data and information. Examples: hard disk

Input Devices

Output Devices

The Parts of A Computer System A computer system consists of four basic units:

1. Hardware

2. Software

3. Data

4. Users

Hardware The mechanical devices that make up the computer are called

hardware. Hardware is any part of your computer that has a physical structure

Hardware is tangible. In other words any part of the computer that you can touch is hardware.

All the input and output devices are the example of hardware Examples : monitor, keyboard, mouse, speaker, scanner

Different forms of

computer hardware

Software Software is a set of instructions that makes the computer

perform tasks. A software tells the computer what to do, when to do and how to do. It is intangible.

A software should have the following characteristics:

1. It is a collection of executable instructions

2. It must manipulate data

3. It should have proper documentation about how to use it Some examples of software are web browsers, games, and word

processors such as Microsoft Word. Other examples: MS word, windows media player, IE, Firefox,

avast antivirus, vlc player, win amp.

Different forms of

computer software

Data Data mean raw, unorganized and unprocessed facts. The word data is the plural of Latin word datum which means

“something given” The primary job of a computer system is to process tiny pieces

of data in various ways and convert them into useful information.

Information means the processed or meaningful data.

User An user is an entity who uses the computer system. Computer users can be divided into five categories:

1. Home user

2. Small office/home office users

3. Mobile users

4. Large business users

5. Power users.

Types of User A home user: spends time on the computer for personal and

business communications, personal financial management, entertainment, and Web access.

A small office/home office (SOHO): user includes any company with fewer than 50 employees, as well as self-employed people that work out of their home.

A mobile user :travels to and from a main office or school to conduct business, communicate, or do homework.

A large business user: works for a company that has a large number of employees and computers usually connected to a network.

The power user : such as an engineer, architect, or desktop publisher – typically works with multimedia, which combines several media elements into one application, and requires the capabilities of a workstation or other powerful computer.

Difference between hardware and software

1. Software is intangible but hardware is tangible

2. Software is developed or engineered, but not manufactured in the classical sense. While hardware is mainly manufactured

3. Software doesn't "wear out” but hardware does

4. Although the hardware industry is moving toward component-based assembly, most software continues to be custom built.

Basic Components of Computer A computer is a programmable electronic device that can receive data as

input, process the received data and convert it into meaningful information as output, which is useful to people. It can also communicate with other devices or computers. It is a high speed electronic machine or data processing machine.

Basic components of a computer:

1. Input Unit

2. Memory Unit

3. Control Unit

4. Arithmetic Logic Unit

5. Output Unit

6. Communication Unit

Central Processing Unit -CPU

Basic Components of Computer

Communication Unit

Communication Unit

Input UnitInput Unit Memory UnitMemory Unit Output Unit

Output Unit

Control Unit

AL Unit

Central Processing Unit [CPU]

Basic Components of Computer Input Unit: input unit accepts data from the user or the input

devices and transfers it to the memory unit. Input devices are keyboard, mouse, scanner, digital camera.

Memory Unit: the function of memory unit is to store data and information received from the input devices. It also supplies data and information to the output unit or to the arithmetic logic unit. Two basic types of memory are: RAM and ROM.

Control Unit: control unit is the basic controller of the computer system. The main function of control unit is to control all the resources of a compute system. It works as the traffic controller of a computer system. It tells the input unit when to receive data from input devices and the output unit when to display a particular information. Any operation that is performed by computer system is performed as the direction of the control unit.

Basic Components of Computer Arithmetic Logic Unit: it is computer’s calculator or brain that

performs all the arithmetic operations such as addition, subtraction, multiplication and division as well as all the logical operations such as AND, OR, NOT etc. It is the data processing unit of the processor or CPU or in other words computer .

Output unit: the function of output unit is to display or show the result or processed data to the user. Examples: monitor, printer.

Communication Unit: the function of communication unit is to perform communication between two or more computers. Examples: hub, switch, modem etc.

How to decide When Buying A Computer

1. Buy based on what you need it for, plus a little more2. Consider your budget3. Do your research4. Know the software inclusion


Buy based on what you need it for, plus a little more: One of the most important considerations when buying a

computer is to see what exactly you will use it for. Models of computers come with different capabilities that there is always a possibility of buying more or less than you really need.

Some uses include: connecting to the Internet, playing games, typing documents, designing websites, programming, digital video or photography, digital scrapbooking, among others.

Some of these need more computing power than others, so be sure how you will use the computer . As a rule of thumb, it is best to buy a little more power than you need, but not far more as it will simply be a waster of money.


Consider your budget: Once you find out exactly what you would be needing your

computer for and the range of specifications that you need your computer to have, consider the amount of money you can afford to spend.

One should compromise on the main parts such as the processor, memory and hard disk space, as this primarily dictates the performance that your system will promise.

Remember that you will be using this system for three or more years. If you do not have enough budget, put off buying a printer or other unnecessary software applications instead.


Do your research: Do not buy the first computer that you see. Gather as much information as you can on the computers that best fits your budget and needs. Try to learn computer terminologies so that you will have an idea about the details that your salesman is talking about.

Know the software inclusion: The last consideration in buying a computer is the software included in the bundle (aside from the Operating System, of course). The most important programs that you would need would be: MS Office, antivirus and firewall. Watch out for trial or limited versions as they do not include the full functionality of the program. Always ask your salesperson about the software included and its versions.

10 Things To Consider When Buying A Computer

1. Usability or users demand

2. Price

3. Operating system type

4. Size of the computer system

5. Peripherals (like scanners, printers)

6. Brand of components (like dvd of sony or asus)

7. Hard disk

8. Ram

9. processor

10. warranty

What is Ergonomics Ergonomics is the study of the physical relationship between

people and their tools like computer. Ergonomics is to design tools to make it working properly

with the human body and thus reduce the risk of strain and injuries.

The purpose of ergonomics is to develop or design user friendly tools or devices for human use.

References

1. Peter Norton's Introduction to Computers, Sixth Edition2. en.wikiperdia.org

MD. Shakhawat Hossain

Student of Computer Science & Engineering Dept.

University of Rajshahi

Education

Introduction to computer