CH-14 INTRODUCTION TO COMPUTER
The impact of
information and communication technology is being felt everywhere and it has brought drastic
change in our present day life. Infact man has entered into an era of ICT with
the invocation of computer. Computer literacy is therefore the need of hour in
this information and technology driven world, '
Now-a-days, computers
are used in every walk of life i.e. education, industry, governance, medicine,
scientific research, law, social sciences, forensic science. defense services,
music and arts. Thus, | computers have become the driving force behind the
development of world. The computer has occupied the prime position as a source
of information. So, it is essential that the future generation should be acquainted
about what computers is, how computer works and how can we use the computers
for communication.
14.1 MEANING OF COMPUTER
(a) Derivative Meaning
or Etymological Meaning: The term “Computer” is derived from the “Latin” word
“compute” which means “to calculate”. Hence, people ritually consider a
computer as calculator device that can perform various arithmetic calculations
at high speed which accuracy.
(b) Word Meaning: The
letters of “Computer” have some specific meaning i.e.
C - Calculate in
O - Operate
M- Memorise
P - Print
U – Update
T - Tabulate
E - _ Edit
R- Response.
General Meaning: A computer
is a machine which works upon information or data and performs number of
operations to analyses the data to draw conclusion.
14.1.1 Definitions
The various definitions
of computer are as follow:
According to V.Gupta,
“A computer is an electronic equipment which is capable of creating solutions by
performing complex processing of information without manual intervention and
that too at a tremendous speed.”
In the words of Donald
H. Sanders “Computer is an electronic symbol manipulating system that is
designed and organized to automatically accept & store input data, process
them and produce output results under the direction of a detailed step by step
stored program of instructions.”
A Computer can also be
defined as an electronic device that is capable of solving problems by accepting
data, performing prescribed operations on the data and supplying the results of
these operations.
In simple words “A
computer is an electronic device which converts raw data into meaningful
information.” A Computer (also known a5 data processor) converts data into information
(Fig. 1.1).
i) Data: The
collection of unarranged facts or raw information is called a Data
ii) Processing: The
sequence of actions carried out on data salaried processing
iii): Information:
information 154 meaningful data, which we get after processing.
In terms of its
function, computer is a machine that can Accept data, store data, process data
as desired, retrieve the stored dotage and when required and print the results
in desired format.
Thus. from the above
discussion, it can be said that Computer is a programmable machine that accepts,
processes and displays data, it stands for Common, Operating, Machine,
Particularly Used for Technical Education and Research.
14.2 IMPORTANT TERMS USED IN COMPUTER SYSTEM
Computer is an
electronic device that accepts data as input, processes the input data by
performing mathematical and logical operations on it, and gives the desired
output. For understanding computer the following terms are important to study.
1. Input/output unit:
The user interacts with the computer via the I/O unit. The Input unit accepts
data from the user and “he Output unit provides the processed data i.e. the
information to ‘he user. The Input unit converts the data that it accepts from
the user, into a form that is understandable by the computer. Similarly, the
Output unit provides the output in a form that is understandable by the user. The
input is provided to the computer using input devices like keyboard, trackball
and mouse. Some of the commonly used output devices are monitor and printer.
2. Central Processing
unit: Central Processing Unit CPU controls, coordinates and supervises the
operations of the computer. It is responsible for processing of the input data.
CPU consists of
Arithmetic Logic Unit
(ALU) and Control Unit (CU).
ALU performs all the
arithmetic and logic operations on the input data.
CU controls the overall operations of the
computer i.e. it checks the sequence of execution of instructions, and, controls
and coordinates the overall functioning of the units of computer.
Additionally. CPU also
has a set of registers for temporary storage of data, instructions. addresses
and intermediate -seats of calculation Memory:
3. Memory Unit: Memory
unit stores the data, instructions, intermediate results and output.
temporarily. during the processing of data. This memory is also called the main
memory or primary memory : of the computer. The input data that is to be
processed is brought into , the main memory before processing. The instructions
required for processing of data and any intermediate results arc also stored in
the main memory. The output is stored in memory before being transferred to the
output device. CPU can work with the information stored in the main memory.
Another kind of storage unit is also referred to as the secondary memory of the
computer. The data, the programs and the output are stored permanently in the
storage unit of the computer. Magnetic disks, optical disks and magnetic tapes
are examples of secondary memory.
4. Data: Data are any facts, numbers, or text
that can be processed by a computer. Today, organizations are accumulating vast
and growing amounts of data in different formats and different databases. This
includes:
Operational or
transactional data such as, sales, cost, inventory, payroll, and accounting
non-operational data, such as industry sales, forecast data, and macro economic data
meta data - data about
the data itself, such as logical database design or data dictionary definitions
5. Information: The
patterns, associations, or relationships among all this data can provide information.
For example, analysis of retail point of sale transaction data can yield
information on which products are selling and when
6. Software: Software
is a collection of instructions, procedures, documentation that performs
different tasks on a computer system. We can say also Computer Software is a
programming code executed on a computer processor. The code can be
machine-level code or the code written for an operating system. Examples of
software are Ms Word, Excel, Power Point, Google Chrome, Photoshop, MySQL etc.
Types of Software
There are two
different types of software:
1. System Software
2. Application
Software
Il. System Software
Software required to
run the hardware parts of the computer and other application software are
called system software. System software acts as interface between hardware and
user applications. An interface is needed because hardware devices or machines
and humans speak in different languages. Machines understand only binary language
i.e. 0 (absence of electric signal) and 1(presence of electric signal) while
humans speak in English, French, German, Tamil, Hindi. and many other
languages. English is the pre-dominant language of interacting with computers.
Software is required to convert all human instructions into machine
understandable instructions. And this is exactly what system software does.
Based on its function, system software is of four types:
(i) Operating System:
System software that is responsible for functioning of all hardware parts and their
interoperability to carry out tasks successfully is called operating system
(OS). OS is the first software to be loaded into computer memory when the
computer is witched on and this is called booting. OS manages a computer’s
basic functions like storing data in memory, retrieving files from storage devices,
scheduling tasks based on priority, etc.
(ii) Language
Processor: As discussed earlier, an important function of system software 1s to
convert all user instructions into machine understandable language. When we
talk of human machine interactions, languages are of three types:
Machine-level language: This language is
nothing but a string of and Is that the machines can understand. It is completely
machine dependent.
Assembly-level language: This language
introduces a layer of abstraction by defining mnemonics. Mnemonics are English
like words or symbols used to denote a long string of and Is. For example, the
word “READ” can be defined to mean that computer has to retrieve data from the memory.
The complete instruction will also tell the memory address. Assembly level
language is machine dependent.
High-level language:
This language uses English like statements and is completely independent of
machines. Programs written using high level languages are easy to create, read
and understand.
Program written in
high level programming languages like Java, C+, etc. is called source code. Set
of instructions in machine readable form is called object code or machine code.
System software that converts source code to object code is called language
processor. There are three types of language interpreters:
Assembler: Converts assembly level program
into machine level program.
Interpreter: Converts high level programs into
machine level program line by line.
Compiler: Converts
high level programs into machine level programs at one go rather than line by
line.
(iii) Device Drivers:
System software that controls and monitors functioning of a specific device on
computer is called device driver. Each device like printer, scanner,
microphone, speaker, etc. that needs to be attached externally to the system
has a specific driver associated with it. When you attach a new device, you
need to install its driver so that the OS knows how it needs to be managed.
ll. Application
Software
A software that
performs a single task and nothing else is called application software.
Application software is very specialized in their function and approach to
solving a problem. So spreadsheet software can only do operations with numbers
and nothing else. Hospital Management software will manage hospital activities
and nothing else. Here are same commonly used application software: -
Presentation
Database management
Multimedia tools
Word processing
Spreadsheet
1.
Hardware:
Hardware refers to the physical components
of a computer. Computer Hardware is any part of the computer the we can
touch these parts. These are the primary electronic devices used to
build up the computer. Examples of hardware in a computes are the
Processor, Memory Devices, Monitor, Printer, Keyboard Mouse, and the Central
Processing Unit. ,
Hardware can be
classified into two categories:
(i) Input Devices: An input device can receive
instructions from users or forward information to another device, but it is not
able to accept data from another system. After receiving input, it translates these
data into the electrical signals in binary code, which cannot be understandable
by humans, and only a digital computer can understand it. There are many
examples of input devices. which are discussed below:
Keyboard and Mouse:
These are the input devices that are used by the users to give input to the
computer. They Send the received Input (Data) from users to the system. As
these are input devices, they cannot receive or display Output i information)
from the computer.
Microphone: Another input
device is a microphone that accepts sound generated by an input source and
allows users to send audio into their computers. In the microphone, the accepted
signal may be converted into a digital signal or can be amplified as an analog
signal.
Webcam: A webcam is a video camera that
connects to a computer and faces the user, which is used to capture pictures,
make a video by a computer system. It takes images as input from where it is
pointed and used for calling and taking selfish. However, most modern webcams
have a microphone, which offers users a better sound quality while making
videos. Webcams are attached to the monitor of a desktop computer and also
built into laptops.
(ii) Output Devices:
Output devices are the section of a computer device that receives data from
another device and produces output with the information. Although it cannot
send data to another device, it has the ability to forward data from a computer
to another computer system. It functions to take data from input devices and translate
the digitized signals into a form that can be understandable by users. There
are various exam] ire discussed below: .
Monitor: A monitor is
a piece of computer hardware that Monitor: from a computer (output) and
displays it on accepts data oh the computer's video card monitors have the
ability to display information at a much higher resolution Additionally these
are much
Speakers: The most common output devices,
speakers accept sound data from a computer and play the sounds for users to
hear. Although speakers can be used with any type of sound system, some speakers
are manufactured only for computers. It
is a device that cannot receive sound generated by users as well as refer that
sound to another device. The main objective of the speakers is to produce sound
or audio output for the listener.
Projector : A
projector is an output device that accepts data fun a computer (output) and
projects that data of formation as a
picture onto a wall or screen or any large ie and t foes not have the ability
to receive data from 4 serene also not capable of sending that data to another «group
of peen you are showing video or images to 4 tree Of a monitor be beneficial to
use ins at ~an be vice cause it displays data on a large surface the to a large
number of people clearly.
14.3 CHARACTERISISTICS OF COMPUTERS
Computer have become
popular in every area of human life. This is because it can do a variety of
tasks crazily which men cannot do easily. The main characteristics that help it
to handle variety of tasks more efficiently and economically are:
1. Speed: A computer
is a very fast acting device. It can carry out even the complex tasks in
fraction of seconds. A simple operation like addition or subtraction is carried
out in Micro second (10-6 sec), or a nanosecond (10-9 sec). Computers are also
known as high speed calculators. Modern computers are able to process millions
or even billions of instructions in a second. We can imagine the high speed of computer
from this fact that human brain can take 40,000 instructions per second and
computer may take up 1,40,000 million instructions per second. The work earlier
carried out in days or years has been performed by computers in few seconds due
to their enormous speed of processing.
2. Accuracy: Besides
the fast speed, computers are very accurate machines. They always produce
accurate results. In simple terms, the computers never make a mistake. It may
be the human or technological weakness that can lead to an error. Computer
errors caused due to incorrect input data or unreliable programs are often referred
as garbage-in-garbage-out (GIGO). The degree of accuracy provided by a
particular computer depends upon its design. A computer performs every calculation
with the same accuracy.
3. Versatility:
Computers are quite versatile is nature i.e. they can perform variety of tasks
simultaneously with equal ease. For example, at one moment it is preparing a letter,
at the same time, it can be used to play music and in between you can print a
document as well. In short, a computer is capable of performing any task which can
be reduced to series of logical steps. It is therefore, engineers and scientists
who make use of this high speed computing device to solve their complex research and design problems.
4. Storage Capability:
A computer can store and recall any information as and when needed. The storage
capacity of computer is very high. It does not make any guess or approximation.
The recalled information is always accurate. The memory of the computer is relatively
small and it can hold only a certain amount of information.
The data is therefore
stored on storage devices such as floppy disks. hard disks. optical disks,
magnetic tapes etc. ACD-ROM can store up to 700 MB of data, while a hard disk
can store up to 80 GB (1 GB=1024 MB) to | TB data, Small sections of the data
can he assessed Very quickly and brought into the storage devices as and when
required, for‘?
Diligence: Computer is
a machine. Therefore, it Never gets bored or tired even if it has to do the
same job again & again. Unlike the human beings, a computer is free from
monotony, tiredness and lack of concentration. It can continuously work for
hours without creating any error and without grumbling. For example if (en
million calculations have to be performed, a computer will perform all of these
with the same accuracy & speed.
6. Power of Remembering:
Power of remembering of the computer is hundred percent. A human being can
forget the information with passage of time but the computer retains the
information without losing the quality of information or data. A computer
forgets & loses information only when it is asked to do so. So it is
entirely up to the user to make a computer retain or forget particular
information.
7. Automation:
Computer is an automatic machine because it works on its own without human intervention.
Once the data and instructions are fed into the computer it processes the data
on its own. Thus, it manipulates the data according to the instructions fed
into it. However. computers being machines cannot start themselves and cannot
go out and find their own problems & solutions.
8. Reliability:
Reliability is the measurement of the efficiency of the performance of a computer.
Computers have the built-in diagnostic capabilities, which help in the
continuous monitoring of the system. Unlike human beings they are capable of
operating under the most adverse conditions with efficiency for longer time
without any fatigue.
9. Consistency:
Computers have high consistency. Outputs of operation are always same when the
same instructions are given Thus, computer can repeat actions consistently
without losing its concentration unlike human beings who have the difficulty in
repeating the actions.
10. Trained Man Power:
A computer system requires trained Personnel to handle it effectively. If any
problem occurs at the time of execution or any logical error occurs on program
then it cannot detect it easily. thus to operate computer, trained personnel is
required. The efforts required in making reliable programmers and the
application logic are unambiguous. on web advertising for generating revenues.
5 Medicine: Medical
researchers and practitioners lies \4 computers to access ‘information about
the advances IN Medical . research or to take opinion of doctors globally. 1 he
medical history of “ patients is stored in the computers. Computers are also AN
integral ‘ part of various kinds of sophisticated medical equipment’s like
ultrasound machine, CAT scan machine,
MRI scan machine, etc. Computers also , provide assistance to the medical surgeons
during critical surgery ; operations like laparoscopic operations, etc.
6. Science and
Engineering: Scientists and engineers use computers for performing complex
scientific calculations, for designing and making drawings (CAD/CA
applications) and also for simulating and testing the designs. Computers are
used for storing the complex data, performing complex calculations and for
visualizing 3- dimensional objects. Complex scientific applications like the
launch of the rockets, space exploration, etc., are not possible without the
computers.
7. Government: The
government uses computers to manage its own operations and also for
e-governance. The websites of the different government departments provide
information to the users. Computers are used for the filing of income tax
return, paying taxes, online submission of water and electricity bills, for the
access of land record details, etc. The police department uses computers to
search for criminals using fingerprint matching, etc.
8. Home: Computers
have now become an integral part of home equipment. At home, people use
computers to play games, to maintain the home accounts, for communicating with
friends and relatives via Internet, for paying bills, for education and
learning, etc. Microprocessors are embedded in house hold utilities like,
washing machines, TVs, food processors, home theatres, security devices, etc. The
list of applications of compute: s is so long that it is not possible to
discuss all of them here. In addition to the applications of the computers
discussed above, computers have also proliferated into areas like banks,
investments, stock trading, accounting, ticket reservation, military’
operations, meteorological predictions, social networking: business
organizations, police department, video conferencing, book publishing. web
newspapers. and information sharing.
14.5 ROLE OF COMPUTER IN EDUCATION
Computer and its
technology has been performed various tale such as tutor, surrogate teacher
eve, in different field of education. UT changed dramatically in the nature of
wav of teaching has been used in classrooms. Computer technology should be used
to reform the teaching methods and curriculum program and the author also
present a report on the usage of computer in the field of education. Computer can
be used in education by three different ways such as “As a teacher”, “Aga
learner”, and “As an assistant”. The following roles of education where computer
has been effectively used as:
1. Distance Learning:
Computer has become an important part of every walk of life such as on campus,
at home and in office. Computer and related technologies have been used in
distance learning through various ways such as Teleconferencing,
video-conferencing, audio graphics, Tele text, video text, multimedia and
hypermedia, e-books, online database, online discussion, on-demand call in
course etc. Virtual classrooms play an important role in distance learning. Students
can raise their doubts and teachers can provide the solutions without going to
one’s place.
2. On-Line examination
and monitoring: Online examination and monitoring system have completely
changed due to the development of modern education technology. These systems
ensure about the fairness and impart laity in the examination. Today, various exams
like GRE, GMAT, SAT, CCNA, MCSE and much more have been conducting computers in
all over the world.
3. Huge &
organized store of information: Vast or Immense storage is yet another main
g-eat characteristic of a computer. Students and teachers can download and
store a lot of educational materials, books, presentations, lecture/ address
notes, question papers, and so on in computers. Students can find many
different ways to solve a certain problem given to them. Through Computer, they
can interact with people having same issues & decisions.
4. Multimedia approach
to education: The growth of audio- visual education has reflected developments
in both teaching and learning theory. Audio-Visual Education, planning,
preparation, and use of devices and materials that involve sight, sound, or
both, for educational purposes.
5. Access to
multiplicity of learning resources: Computer education is the resources to
enhance the teaching skills and learning ability. It is easy to provide audio
visual education. Computer education encouraged the learners for their studies.
6. Any time learning: Computer education has
provided nearness to education. Now a day’s computers and web networks imparting
knowledge of the student. Computer education is very fast and one can be
educated anywhere at any time.
7. Concerted learning:
Computer education has made it cash to study as well as teach in groups. With
online we can together to do the desired task.
8. Authentic and up to
date information: The information and data which are available on the net is up
to date. Internet, a collection of computer networks that operate to common
standards and enable the computers and the programs they run to communicate
directly provides true and correct information.
9. Online library:
Internets support thousands of different kinds of effective and new services
one of which is online library. We can get sufficiently of data on this online
library.
The above points show
the importance of computer in education because if computers are not part of it,
you may not get your desired job. The entire process of learning becomes much
more fun and exciting because of the different tools and programs that a
computer typically has,
EXERCISE
1.
What is
computer? What are the functions of computer?
2.
What are
the main components of computer?
3.
Differentiate
the hardware and software in detail?
4.
What is
computer? Discuss its characteristics?
5.
Elaborate
the role of computer in the field of education?
6.
How can
computer make teaching learning process more interesting and effective?
7.
Discuss
the applications of computer in detail?
