Introdution to Information Technology

8/13/2019 Introdution to Information Technology

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INTRODUCTION TO INFORMATION TECHNOLOGY


SYLLABUS

Unit1:

Introduction: Information System-Software and data-Business and industry-IT in home

And at play-IT in education and training-IT in entertaining and the Arts IT in Science,

Engineering and Mathematics-Computer in hiding.

Unit 2:

The Computer System and Central Processing Unit: types of computers-Corporate

and departmental computers, desktop computers and personal computers-The anatomy of

computer-The foundation of Modern Information Technology: Binary numbers, Digital

Signals, Bit and Bytes-Central Processing Unit-Memory.

Unit 3:

Input and Output: I/O Devices-Keyboards-Inputting text, Graphics-Pointing Devices-The

foundation of Modern Outputs: Pixels and Resolutions, Fonts, Color-Display Screens-Printers Secondary Storage The foundation of Modern Storage: How data is Stored-

Storage Characteristics-Storage Media-Floppy Disk, Hard Disk, Drives, Optical Disk-

Backing up Data

Unit 4:

Software-Introduction-User Interface-Application Programs-Operating System:

Introduction-Types, File management and Utilities-Major Software Issues.

Unit 5:

Internet and World wide Web: Introduction-The web-getting connected to the web-

Browsing the web- locating the information on the web- Web multimedia


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Text book:

Information Technology the Breaking Wave By Dennis P.Curtin,kim foley,kernel

sen,Cathleen mortin-Tata MC GrawHill publishing


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Unit I

INFORMATION SYSTEMS:

Introduction:

Information Systems (IS) is an academic /professional discipline bridging the

business field and the well-defined computer science field that is evolving toward a new

scientific area of study. An information systems discipline therefore is supported by the

theoretical foundations of information and computations such that learned scholars have

unique opportunities to explore the academics of various business models as well as

related algorithmic processes within a computer science discipline. Typically,

information systems or the more common legacy information systems include people,

procedures, data, software, and hardware (by degree) that are used to gather and analyze

digital information. Specifically computer- based information systems are complementary

networks of hardware/software that people and organizations use to collect, filter,

process, create, & distribute data (computing).

Computer Information System(s) (CIS) is often a track within the computer

science field studying computers and algorithmic processes, including their principles,

their software & hardware designs, their applications, and their impact on society.

Definition

Information systems are implemented within an organization for the purpose of

improving the effectiveness and efficiency of that organization. Capabilities of theinformation system and characteristics of the organization, its work systems, its people,

and its development and implementation methodologies together determine the extent to

which that purpose is achieved.
http://en.wikipedia.org/wiki/Academichttp://en.wikipedia.org/wiki/Professionalhttp://en.wikipedia.org/wiki/Businesshttp://en.wikipedia.org/wiki/Computer_sciencehttp://en.wikipedia.org/wiki/Informationhttp://en.wikipedia.org/wiki/Computationshttp://en.wikipedia.org/wiki/Algorithmichttp://en.wikipedia.org/wiki/Datahttp://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Data_%28computing%29http://en.wikipedia.org/wiki/Data_%28computing%29http://en.wikipedia.org/wiki/Computerhttp://en.wikipedia.org/wiki/Digitalhttp://en.wikipedia.org/wiki/Datahttp://en.wikipedia.org/wiki/Algorithmichttp://en.wikipedia.org/wiki/Computationshttp://en.wikipedia.org/wiki/Informationhttp://en.wikipedia.org/wiki/Computer_sciencehttp://en.wikipedia.org/wiki/Businesshttp://en.wikipedia.org/wiki/Professionalhttp://en.wikipedia.org/wiki/Academic


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Types of information systems:

The 'classic' view of Information systems found in the textbook s[30] of the 1980s

was of a pyramid of systems that reflected the hierarchy of the organization, usually

Transaction processing systems at the bottom of the pyramid, followed by Management

information systems, Decision support systems and ending with Executive information

systems at the top. Although the pyramid model remains useful, since it was first

formulated a number of new technologies have been developed and new categories of

information systems have emerged, some of which no longer fit easily into the original

pyramid model.

Some examples of such systems are :

Data warehouses

Enterprise resource planning

Enterprise systems

Expert systems

Geographic information system

Global information system

Office Automation

COMPUTER SOFTWARE

A software, is a collection of computer programs and related data that provide the

instructions telling a computer what to do and how to do it. We can also say software refers

to one or more computer programs and data held in the storage of the computer for some

purposes. In other words software is a set of programs, procedures, algorithms and its

documentation. Program software performs the function of the program it implements,

either by directly providing instructions to the computer hardware or by serving as input to

another piece of software. The term was coined to contrast to the old term hardware

(meaning physical devices). In contrast to hardware, software is intangible, meaning it

"cannot be touched". Software is also sometimes used in a more narrow sense, meaning
http://en.wikipedia.org/wiki/Information_systems#cite_note-29http://en.wikipedia.org/wiki/Information_systems#cite_note-29http://en.wikipedia.org/wiki/Information_systems#cite_note-29http://en.wikipedia.org/wiki/Transaction_processing_systemshttp://en.wikipedia.org/wiki/Management_information_systemshttp://en.wikipedia.org/wiki/Management_information_systemshttp://en.wikipedia.org/wiki/Decision_support_systemshttp://en.wikipedia.org/wiki/Executive_information_systemshttp://en.wikipedia.org/wiki/Executive_information_systemshttp://en.wikipedia.org/wiki/Global_information_systemhttp://en.wikipedia.org/wiki/Office_Automationhttp://en.wikipedia.org/wiki/Office_Automationhttp://en.wikipedia.org/wiki/Global_information_systemhttp://en.wikipedia.org/wiki/Executive_information_systemshttp://en.wikipedia.org/wiki/Executive_information_systemshttp://en.wikipedia.org/wiki/Executive_information_systemshttp://en.wikipedia.org/wiki/Decision_support_systemshttp://en.wikipedia.org/wiki/Management_information_systemshttp://en.wikipedia.org/wiki/Management_information_systemshttp://en.wikipedia.org/wiki/Management_information_systemshttp://en.wikipedia.org/wiki/Transaction_processing_systemshttp://en.wikipedia.org/wiki/Information_systems#cite_note-29


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application software only. Sometimes the term includes data that has not traditionally been

associated with computers, such as film, tapes, and record

Examples of computer software include:

Application software includes end-user applications of computers such as word

processors or video games, and ERP software for groups of users.

Middleware controls and co-ordinates distributed systems.

Programming languages define the syntax and semantics of computer programs.

For example, many mature banking applications were written in the COBOL

language, originally invented in 1959. Newer applications are often written in

more modern programming languages.

System software includes operating systems, which govern computing resources.

Today large applications running on remote machines such as Websites areconsidered to be system software, because ] the end-user interface is generally

through a graphical user interface, such as a web browser.

Testware is software for testing hardware or a software package.

Firmware is low-level software often stored on electrically programmable

memory devices. Firmware is given its name because it is treated like hardware

and run ("executed") by other software programs.

Shrinkware is the older name given to consumer-purchased software, because it

was often sold in retail stores in a shrink-wrapped box.

Device drivers control parts of computers such as disk drives, printers, CD drives,

or computer monitors.

Programming tools help conduct computing tasks in any category listed above.

For programmers, these could be tools for debugging or reverse engineering older

legacy systems in order to check source code compatibility.

DATA:

The term data refers to qualitative or quantitative attributes of a variable or set of

variables. Data (plural of "datum") are typically the results of measurements and can be

the basis of graphs, images, or observations of a set of variables. Data are often viewed as

the lowest level of abstraction from which information and then knowledge are derived.
http://en.wikipedia.org/wiki/Testwarehttp://en.wikipedia.org/wiki/Variable_%28mathematics%29http://en.wikipedia.org/wiki/Graph_%28data_structure%29http://en.wikipedia.org/wiki/Imagehttp://en.wikipedia.org/wiki/Abstractionhttp://en.wikipedia.org/wiki/Abstractionhttp://en.wikipedia.org/wiki/Imagehttp://en.wikipedia.org/wiki/Graph_%28data_structure%29http://en.wikipedia.org/wiki/Variable_%28mathematics%29http://en.wikipedia.org/wiki/Testware


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Raw data , i.e. unprocessed data, refers to a collection of numbers, characters, images or

other outputs from devices that collect information to convert physical quantities into

symbols.

1) Distinct pieces of information, usually formatted in a special way. All software is

divided into two general categories: data and programs . Programs are collections of

instructions for manipulating data.

Data can exist in a variety of forms -- as numbers or text on pieces of paper, as bits and

bytes stored in electronic memory, or as facts stored in a person's mind.

Strictly speaking, data is the plural of datum , a single piece of information. In practice,

however, people use data as both the singular and plural form of the word.

(2) The term data is often used to distinguish binary machine-readable information from

textual human-readable information. For example, some applications make a distinction

between data files (files that contain binary data) and text files (files that contain ASCII

data).

(3) In database management systems, data files are the files that store the database

information, whereas other files, such as index files and data dictionaries, store

administrative information, known as metadata.

IT IN BUSINESS:

Introduction:

At present, computers are used for every business transactions. The following are some

of the business transactions in which computers are successfully used:

I . Preparati on of wage sheet.

I I . I nventory control.

I I I . M aintenance of r ecords.

I V. Providing summarized in for mation requir ed by the management.

V. Banking transactions.
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VI . Preparati on of accounts and r ecords for in sur ance companies.

IT in business:

In todays highly competitive economic environment having the right IT in business is a critical element of success. All businesses deal with some of the new

technology whether it is just a basic computer system or highly sophisticated software to

track sales from the time the initial contact is made until they close. Finding the right IT

personnel or company to provide the right systems is not as hard as it may first appear.

There are man y opportunities right on the Internet to find the right IT in business help. If

sales companies are doing business on the Internet there is the opportunity to find good

Contact Management Systems (CMS) and Search Engine Optimization (SEO) software.

The CMS software provides sales force managers with all of the tools necessary to

monitor the status of the potential sales that are being worked by the members of the sales

team.

SEO software is the IT in business solution to propel a business website to high rankings

on major Internet search engines like Google, Yahoo, and MSN. This brings targeted

visitors to the website and leads to more contacts and more sales. Businesses that fail toget visitors to their website on a regular and continuing basis are usually not going to

succeed.

The IT in business solutions are available and affordable for businesses both large and

small. It is important to do some research to find the right company with a good

reputation and that provides the services needed. Once that is done, any business can

make the necessary moves to get a step ahead of the competition.

IT IN INDUSTRY:

Introduction:

In industries, computers are used to control the operation of machineries. The uses of

computers in various industries are as follows:


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I . Computers are helpfu l in process contr ol i n paper, sugar , ir on and steel,

chemical industr ies and oil r efi neries. Thi s control li ng techni que wil l i ncrease

productivity by reducing wastage.

I I . I n pr in tin g industry, computers are useful for pr in ting news papers, magazin esand books speedily.

I I I . They are helpful in designi ng machineries, motor vehi cles, shi ps, air crafts and

bridges.

I V. The electr ici ty boards are usin g computers to contr ol voltage fl uctuati ons.

Information Technology In Industry:

Information technology, and the hardware and software associated with the IT

industry, are an integral part of nearly every major global industry.

The information technology (IT) industry has become of the most robust industries in theworld. IT, more than any other industry or economic facet, has an increased productivity,

particularly in the developed world, and therefore is a key driver of global economic

growth. Economies of scale and insatiable demand from both consumers and enterprises

characterize this rapidly growing sector.

The Information Technology Association of America (ITAA) explains 'information

technology' as encompassing all possible aspects of information systems based on

computers.

Both software development and the hardware involved in the IT industry include

everything from computer systems, to the design, implementation, study and

development of IT and management systems.


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Owing to its easy accessibility and the wide range of IT products available, the demand

for IT services has increased substantially over the years. The IT sector has emerged as a

major global source of both growth and employment.

Features of the IT Industry at a Glance

Economies of scale for the information technology industry are high. The

marginal cost of each unit of additional software or hardware is insignificant

compared to the value addition that results from it.

Unlike other common industries, the IT industry is knowledge-based.

Efficient utilization of skilled labor forces in the IT sector can help an economy

achieve a rapid pace of economic growth.

The IT industry helps many other sectors in the growth process of the economy

including the services and manufacturing sectors.

IT AT PLAY:

In past years, both the Vancouver Whitecaps and Montreal Impact have claimed

underdog status when facing Toronto in Nutrilite Canadian Championship play.

As division two teams, it was part of their rallying cry against Canada's lone MLS side.

Now with Vancouver in MLS, too, and Montreal still a year away, Impact head coach

Marc Dos Santos was quick to play that card after practice in Saint-Leonard on Monday.

"We're not in the MLS," he said. "We don't have the budget Vancouver has. We know all

the odds are for them.

"They should beat us, if it's normal. But we hope it's not normal. We hope we can be a

team that can surprise them."


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It's a trick Montreal has pulled off before. They won the 2008 Nutrilite tournament and,

as Canada's qualifier for the CONCACAF Champions League, made a memorable run to

the quarterfinals, playing Mexican side Santos Laguna in front of 55,000 fans at Olympic

Stadium. The Impact aren't alone in their David vs. Goliath mentality this year. The

tournament has expanded from three to four teams with the addition of seconddivision

side Edmonton, who will face Toronto in the other two-leg semifinal.

"Vancouver is a team built with Teitur's identity, but with more quality players. Alain

Rochat is better than Nelson Akwari. [Davide] Chiumiento brings a lot and you have the

addition of [Eric] Hassli and Atiba Harris and Camilo -those three are better than any

forward Vancouver's had in the past."

Montreal's makeover includes the retirement of colourful defender Adam Braz and classy

striker Eduardo Sebrango.

The Impact added experience in 28-yearold midfielder Luke Kreamalmeyer and 29-year-

old goalkeeper Bill Gaudette, whom Caps fans will remember from the Puerto Rico

Islanders.

Left back Zurab Tsiskaridze, one of the fan favourites at Swangard Stadium last season,

joined after Thordarson released him in the off-season.

The Impact have kept their core largely intact with captain Nevio Pizzolitto, Leo Di

Lorenzo and David Testo all returning. "We're coming in as underdogs," Dos Santos said,

"and that can be an advantage for us."

IT IN EDUCATION:

Introduction :As regards education, computers are used in teaching the subjects and maintain

books in the libraries. Particularly it is a gift of God for the students studying science and

engineering Computer Aided Education(CAE) and Computer Based Training (CBT)

packages are making learning more interactive.


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IT in education - for students

Because IT is so powerful, it can be used at all levels of education and training,from primary to higher education and in the workplace. In certain situations IT can

probably be more effective than any other media, for example in

dynamic graph drawing

models which are under student control

simulations to save equipment and laboratory animals

drill and practice to replace material often covered poorly in crowded tutorials

illustrated lecture to improve visual communication

With lectures, students need to absorb material at a fixed rate, or make good notes. CAL

can be used at the students optimum pace. Test results seem to indicate that the material

covered by their courseware is more accessible, and offers more opportunity for practise

on a computer, than in textbooks and lectures.

Education in IT - for students

There is, of course, a need for any country to have enough trained electronics engineers

and computer scientists. But it is essential for a much larger number of employees to have

a wide range of practical IT skills. It is also important for them to have m ore general

skills in lifelong learning. Evidence is emerging that early learning of study skills can

make students more effective learners overall. These can be skills in using IT for

studying, or more general skills learned through IT. It should be worth students being

educated in IT to be able to make full use of:

Productivity Tools

numerical processing spreadsheets, statistics

programming


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word processing

graphic design

database analysis & management

Internet information access

control of equipment & instruments, data capture

desktop publishing

presentations

integrated work environment

Communication tools

electronic mail and file transfer

conferencing

collaborative work

gateway to information & data banks

the internet and the World Wide Web

IT in Education - for students

As well as using IT tools in learning, computer based learning materials can provide

powerful aids to all students, in many different ways:

guide

aid

discovery learning

microworlds

games

simulation

modelling

visualisation

animation

instructor

tutorial


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interactive multimedia

problem solving

drill & practice

revision resource

assessment - formative & summative

integrated learning systems

Adult access to learning technologies

The flexibility of IT for learning allows adults and others outside of full-time attendance

at schools and universities to learn in their own time. IT can add a great extra value to the

distance learning, such as is provided by an open learning university.

Level of technological skill needed by teachers

We have carefully evaluated a wide range of IT uses for learning. Some require large

teams of many specialists to produce and deliver learning materials. Others need only

normal staff levels of IT skills (eg wordprocessing, spreadsheets etc). Others need very

little IT skill - we have found that some staff can assist students using computers with

learning difficulties in their subject content without needing to support the students with

their IT skills. There is no single level of minimum IT skill needed.

Staff in teaching teams need a wide range of skills to succeed in providing IT for

learning:

teaching in schools/ further education / higher education

computer science, programming

information handling: text,library, database, internet

graphic design

Interface/interaction, HCI design

CBL/CAL development/authoring

commercial/project management

specialist academic subject knowledge

evaluation, learning research


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technical/creative writing

Design/development/adaptation/integration of learning material into courses

There are several ways to provide learning materials:

The lone worker makes a simple package.

Teacher(s) apply software shell, institutionally-devised or supported.

Teachers use team of specialists in package development:

o with members residing mainly together in a department,

o or in a centrally-funded hyper/multimedia unit.

IT IN TRAINING:

Staff training, training the trainers

All teachers who may use IT need basic training, and their trainers need very

extensive training to keep the teachers up to date and efficient. However, teachers usually

have the most important skill already - experience in using whatever resources they ca n

find to help the students learn.

Investment in IT & education - for a nation

Employers needs for IT skilled workers

As IT pervades all business and industrial enterprises, employers need workers skilled in

all aspects of IT, and rely on the education system as well as their own training schemes.

Computer and network infrastructures

Each enterprise and educational establishment needs to invest in computers and networks,

coordinated nationally, and linked to the internet.


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Making investment decisions

IT affects strategic issues, accounts for large expenditures, competes for resources, is

complex, and could eventually become at the core of educational processes. Your

approach to evaluating costs and benefits depends on whether you are interested in big

issues or local ones. Education is an investment in the future of a nation. To educational

economists the evaluation of costs and benefits of education must include all costs and all

benefits to the whole of society. These considerations would be applied, for example, to

whether or not the government should subsidise a special loan scheme for mature

students to buy computers. Accounting and estimating must find a monetary value for all

factors, with discounting rates appropriate to a whole economy.

identify driving problems and opportunities

identify objectives of students, teachers, the institution, the nation

identify and develop the possible alternatives

chose criteria for evaluating inputs & outputs, costs & benefits

consider all types of cost & benefits - identify

o those which are not relevant,

o those which are under your influence,

o and those which may need action beyond your controlestimate relevant costs in money and other terms

estimate relevant benefits as satisfactory/unsatisfactory or on a points scale

estimate levels of confidence, risks if wrong, sensitivity to errors

compare costs & benefits of each alternative

consider wider implications of the direct change and consequential changes

o - go beyond economics and accountancy methods

o and evaluate the softer benefits, the impacts in human and organisational

terms

IT solutions - studies of worthwhile investments

Communication and conferencing, collaborative learning & group work


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Automating processes

o computer based assessment

o drill and practise

Finding learning material through the internet and the World Wide Web

Importing learning packages

o software produced commercial or by educators

Customising and recycling learning packages

o adapting modular and adaptable packages for local use, modifying over

several years classes to improve effectiveness

Low-cost locally-produced learning packages

o using standard software: word processing,spreadsheet, database, statistics,

maths solving, presentation, html/Web viewersusing learning material made in student projects

using a template or shell

using operating system extensions.

Producing high cost packages for high-quality learning,

o but with a high costs of authoring, so do not do this unless expecting large

benefits, large external sales, or collaborating with other institutions to

share the costs and the market.

Using IT for organisation of education, and training of staff

o CAL delivers efficient training, including in IT skills

IT IN ENTERTAINMENT

Introduction:

Computers are extensively used in designing and drawing by engineers and

architects. Computers can create objects that can be viewed from all the three

dimensions.

The entertainment industry is one of prompt and complicated change. New technologies


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require updated operating procedures within the enterprise, while increasing demands

from business partners and consumers alike create new challenges and opportunities.

Several strategic imperatives drive the future success of entertainment companies.

We combine domain experience with background in delivering enterprise application

solutions by leveraging the Oracle e-Biz. Our expertise, clubbed with proven

methodologies offers the entertainment companies competitive advantage in mastering

fast changing markets.

IT IN SCIENCE:

This collection of case studies from the art and design higher education

community came about as a result of a meeting held at Loughborough University in April

of last year. This meeting was held in response to an invitation to the art and design

community from AGOCG aimed at discovering the relevance of the activities of AGOCG

to this group of computer graphics users. Although this group obviously has a major

interest in computer graphics there are two main reasons for lack of contact in the past.

Firstly, nearly all art and design departments in higher education have existed as stand

alone institutions or faculties within polytechnics and therefore only recently came under

the remit of HEFCs, and secondly AGOCG itself grew out of the scientific graphicsvisualisation community.

There was therefore little knowledge of each others activities, interests and

preoccupations, and no clear indication of whether there could be any potential benefit

for a closer understanding of the areas of mutual interest.

An outcome of the meeting was an open call for case studies in order to start the

process of exchanging information.

A simple analysis of the studies that have been received by AGOCG shows that

the largest single category concerns the descriptions on the use of CAD systems in three

dimensional design courses, closely followed by Hypermedia applications to design

courses. After these two categories have been satisfied the studies become more


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individual and particular. There is a keen interest in the use of the World Wide Web,

particularly among fine artists, and considerable discussion on the detailed merits of

individual drawing\painting\modelling software, used by fine artists.

What has materialised is a very fair and representative cross section of the

computer graphics interests to be found in the art and design sector of higher education.

An early observation could be made that there is almost universal acceptance and use of

application software, so there is a strong 'user' community without any strongly

developed appreciation of the potential for software development. There is also a strong

Macintosh using group which is a rarity in the 'old' universities, whose needs will need to

be considered. I also sense that there is patchy technical support for art and design users

whose needs may differ from the average users.

However it is much too early to come to any firm conclusions; I believe there is

much to be learned and I hope that AGOCG will continue to foster a debate which will

serve to ensure that all aspects of the use of computer graphics are kept under

consideration.

IT IN ENGINEERING:

In recent years, architecture, engineering, and construction (AEC) practitionershave been faced with a large and increasing array of new information technology (IT)

products and services as IT has become the dominant technology in modeling AEC

projects.

It is contended that models need to be multidisciplinary to accommodate the

interacting aspects of AEC projects. It is further claimed that managing with particular

business objectives in mind and making a commitment to publicly track performance in

these areas will make it possible both to extract predictable value from the models and to

determine which IT applications to implement and when to implement them.

COMPUTERS IN HIDING:


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Computers are often used to store private information, and we often want to share

parts of it without giving up our full privacy.

This activity shows a surprising technique discovered by computer scientists that

seems impossible; it allows people to share personal certain kinds of information

accurately without having to give up any privacy at all


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Unit II

The Computer System and Central processing unit

TYPES OF COMPUTER

Different types of computer systems are nowadays available for different purposes

according the user needs.

Personal computers or microcomputers

Microcomputers are built to be used by one person. In fact when you talk about

personal computers or its common acronym PC, you always mean microcomputers. For

surfing the web, playing games or music, editing and many other tasks you ordinarily

use personal computers either at school, at home or at business.

Personal computers in two (2) major types: desktop and laptop.

If you opt for a desktop computer you have to set it up in a permanent location.

Fortunately you are able to choose your preferred sizes such as a mini, mid or full tower.

Add many other devices to complete it such as keyboard, mouse and monitor which can

be a CRT or LCD display.

Workstations and Servers

If we need a high-end micro computer we should go for a workstation. This typeof computer is recommended if we are working in game development, scientific

calculations, engineering or 3D graphics. It is fastest than the common personal computer

and even it can be used as server if we need to build a basic network client by example.
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The server is generally used for a major client with the purpose to allow many

users working together over a network. Servers require powerful processors, large

amount of hard disk drives and ram memory.

Mobile computers

If we prefer the laptop we ll go for the mobile or portable system. Your notebook,

a common name of laptop, has the advantage to have all the parts built together.

notebook has the same computing power to the desktop machine but it is enough

lightweight to be portable. If the mobile machine is relatively more expensive its because it costs more to design the small components.

Maybe well need greater portability. So a handheld micro computer is your first option.

To manage your phone book, diary or taking notes...etc a Personal Digital Assistant

(PDA) is useful.

we can also use the Palmtop, a tinier laptop than the PDA, to the same purposes and even

more. The Palmtop is designed with a small keyboard and a flip-up screen and is more

usable to surf the web while we are on the move.

Mini computers

Apart the micro computers, we may consider three other types of computers: the

minicomputers, the mainframes and the supercomputers.
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Be advised that the name minicomputers does not mean it is slowest than our PC.

Surely not! If we plan to build a home network the minicomputers can be used as a mid-

range server to serve multiple users.

However with the mainframe you are able to build a large network for several

hundred clients. we can process millions of transactions daily with the mainframe

because of its high capacity. Most of enterprises such as large organizations, insurance

businesses, industry, banking usually use the mainframe for processing and storing

enormous amounts of data every day.

The supercomputer is the fastest machine in the history of computer not only for

its size but especially for its capacity. We wont have to use this powerful system unlesswe are working with nuclear or aerodynamic companies for example.

Conclusion:

Through this brief description you had opportunity to learn a lot about the different

generation of computer. Nowadays many electronics devices are working like computers.

our iPod, our cell phone or even our watch has an integrated computer application. In the

near future we cant imagine what we are expected as newer types of compute

ANATOMY OF COMPUTER:

Monitor- Commonly known as a "screen," the monitor gives you a visual display

of what your computer is up to. Monitor displays are divided into pixels. The higher the

pixel count, the higher the "resolution." Resolutions are measured in Rows x Columns.

Common resolution settings are 640 x 480, 800 x 600, 1024 x 768, 1280 x 1024, etc.

There are two basic types of monitors, the CRT and the LCD.

CRT (Cathode Ray Tube) Monitors are built very similarly to older

(tube) television sets. They are heavy, bulky, take up a lot of desk space,

and emit radiation that can be harmful to humans.


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LCD (Liquid Crystal Display) Monitors are thin and flat. They are light,

compact, take up very little desk space (or you can get funky and mount

them to a wall and save ALL your desk space), emit no known radiation,

but are typically darker in aspect than their fatter cousins.

Mouse- The mouse is the most basic of input devices for a

computer.You use it like you would your finger or hand to interact

with objects on your display. A mouse can be wired or wireless, PS2

or USB, and be optical, laser, or have a ball that it rides on.

Keyboard- The keyboard allows you to input data into your

computer. It too can be wired or wireless, PS2 or USB. The

keyboard shown on the left is a "natural" keyboard that is split in

the middle and curved to account for the shoulder width of the

person using it.

Computer- The computer is a wondrous device that collates and

processes information. There's not enough room on this

entire website to list and describe all of the things a computer can

do. Computers come in thousands of shapes and sizes. To the

left is a "Desktop Tower" mode


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CPU- CPU is short for Central Processing Unit, and (you guessed it) it does all (well, in

some cases only most) of the processing in your computer. CPUs come in a wild variety

of shapes, sizes, socket sets, and architectures. Shown on the left is an Intel Core 2 Duo

CPU (and it's like pornography to nerds). All you will probably ever need to know about

CPUs is that GHz are better than MHz, and the higher the

GHz the better (as long as you can cool the CPU adequately).

Motherboard- The Motherboard (or Mainboard) is actually even

more central than the Central Processing Unit. It hosts the socket

or connection with which every device in a computer is housed or

controlled. Motherboards are like brains, in that if you have to foolaround with one, you should have professional help.

Memory- Here's one that is commonly mistaken. You get an error

message on your machine that basically tells you that you don't have

enough memory to do whatever it is you asked it to do. This does not

refer to hard drive space. Memory, also known as RAM, is what enables

your computer to open files stored permanently on your hard drive. Lots

of RAM is good. Lots of RAM is VERY good. What constitutes a lot of

RAM changes every year. For Windows 2000, 256MB of RAM is required to operate

comfortably. For Windows XP, 512MB (2 x 256MB) of RAM is required to operate

comfortably. For Windows Vista, 1GB (2 x 512MB) of RAM is required to operate

comfortably. Memory modules (called sticks, usually) plug into slots on your

Motherboard.

Hard Drive- A Hard drive is a series of magnetic platters on an axle

or spindle that stores tiny bits of magnetic metal in patterns that it can

read later. It uses a series of tiny little arms that wave back and forth

above, below, and between the platters, to read and write, using these

magnetic metal bits. The platters, spindle, and arms are all contained in


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a small, hermetically sealed metal chamber. Hard drives are what hold all the information

in your computer that does not go away when you turn it off and back on again. If your

hard drive starts making strange grinding or tapping noises, please turn it off and get it to

a REAL professional as soon as possible, as it is about to fail and probably take all your

information with it. Hard drives are fickle, fragile, and prone to failure, which is why it is

so darn important to backup your data often and well. Hard drives plug into IDE, SCSI,

or SATA Cables, which plug into IDE, SCSI, or SATA slots on your

Motherboard.

Optical Drive- An Optical Drive is a method for taking large amounts

of information and storing it on shiny Disks, like CDs and DVDs.

Optical drives use lasers to read from this media, and in some cases, to

write to it. Optical drives plug into IDE, SCSI, or SATA Cables, which plug into IDE,SCSI, or SATA slots on your Motherboard.

Expansion Cards- This is the part where I cheat a little bit and don't

describe every type of expansion card that there is. Expansion cards

include Video Cards, Sound Cards, Modems, Network Interface Cards,

Wireless Network Interface Cards, SCSI Cards, IDE Device cards, and

many more. Expansion cards plug into PCI, AGP, ISA, or PCIe slots on

your Motherboard.

Power Supply- Power supplies take the nasty 110 Volts AC

from your wall outlet and turn it into nice clean DC voltage

that your computer likes to eat. Power supplies are neat, fan-

cooled little boxes with tons of little tiny wires coming out.

Power supplies plug into a special slot on your Motherboard

(which also controls them and turns them on and off) and also

into every power hungry device in your computer.

THE FOUNDATION OF MODERN INFORMATION TECHNOLOGY:
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Binary Digits

Binary Numbers

A Binary Number is made up of only 0s and 1s.

So each digit has only two possibilities: 0 or 1

Bits

In the computer world "binary digit" is often shortened to the word "bit"

More Than One Digit

So, if one digit has only two possible "positions" (like "0" and "1" , or "On" and "Off" ),

how many positions are there with 2 or more binary digits?

For example, different ways could 4 digits be set (Let's write them all down, starting with

1 digit )

One digit will have 2 positions... 0

1

...two digits have 4 positions...0

0 00

1 01

10 10

1 11

...three digits have 8 positions... 0

00 000

1 001

10 010

1 011

1 0 0 100
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1 101

10 110

1 111

... and four digits have 16 positions.

0

0

00 0000

1 0001

10 0010

1 0011

1

00 0100

1 0101

1 0 01101 0111

1

0

00 1000

1 1001

10 1010

1 1011

10

0 1100

1 1101

10 1110

1 1111

And, in fact, we have created the first 16 binary numbers :

Decimal: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Binary: 0 1 10 11 100 101 110 111 1000 1001 1010 1011 1100 1101 1110 1111

This is quite a useful thing to remember. If you forget how the sequence of binary

numbers go, just think:

"0" and "1" {0,1}
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then "0" and "1" again but with a "1" in front: {0,1,10,11}

then take those four with "1"s as a third digit: {0,1,10,11,100,101,110,111}

and so on!

Or just count exactly like decimal numbers, but don't use 2,3,4,5,6,7,8 or 9.

Binary Digits ... They Double !

Also notice that each time we add another binary digit you double the possibilities. Why

double ? Because we have to take all the previous possible positions and match them with

a "0" and a "1" like above.

So, if you had 5 things, then the total would be 32, 6 things would be 64, etc.

Using exponents , this can be shown as:

No of Digits Formula Settings

1 2 2

2 2 4

3 2 8

4 2 16

5 2 32

6 2 64

etc... etc. .. etc...

Example: when we have 50 binary digits (or even 50 things that can only have two

positions each), how many different ways is that?

Answer 2 50 = 2 2 2 2 ... (fifty of these) = 1,125,899,906,842,624

So, a binary number with 50 digits could have 1,125,899,906,842,624 different values.
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Or to put it another way, it could show a number up to 1,125,899,906,842,623 (note: this

is one less than the total number of values, because one of the values is 0).

Digital signals:

Digital signals consist of patterns of bits of information. These patterns can be

generated in many ways, each producing a specific code. Modern digital computers store

and process all kinds of information as binary patterns. All the pictures, text. sound and

video stored in this computer are held and manipulated as patterns of binary values.

The main advantage of digital signals over analog signals is that the precise signal level

of the digital signal is not vital. This means that digital signals are fairly immune to the

imperfections of real electronic systems which tend to spoil analog signals. As a result,

digital CD's are much more robust than analog LP's.

Codes are often used in the transmission of information. These codes can be used either

as a means of keeping the information secret or as a means of breaking the information

into pieces that are manageable by the technology used to transmit the code, e.g. The

letters and numbers to be sent by a Morse code are coded into dots and dashes.


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BIT AND BYTES :

Bit:

A bit (contraction of binary digit) is the basic unit of information in computing and telecommunications ; it is the amount of information stored by a digital device or

other physical system that exists in one of two possible distinct states . These may be the

two stable states of a flip-flop , two positions of an electrical switch , two distinct voltage

or current levels allowed by a circuit , two distinct levels of light intensity , two directions

of magnetization or polarization , etc.

In computing , a bit can also be defined as a variable or computed quantity that can have

only two possible values . These two values are often interpreted as binary digits and areusually denoted by the Arabic numerical digits 0 and 1. Indeed, the term "bit" is a

contraction of binary digit . The two values can also be interpreted as logical values

(true / false , yes/no), algebraic signs (+ / ), activation states ( on /off ), or any other two-

valued attribute. In several popular programming languages, numeric 0 is equivalent (or

convertible) to logical false , and 1 to true . The correspondence between these values and

the physical states of the underlying storage or device is a matter of convention, and

different assignments may be used even within the same device or program .

In information theory , one bit is typically defined as the uncertainty of a binary random

variable that is 0 or 1 with equal probability, or the information that is gained when the

value of such a variable becomes known.

Byte:

The byte is a unit of digital information in computing and telecommunications ,

that most commonly consists of eight bits . Historically, a byte was the number of bits

used to encode a single character of text in a computer and it is for this reason the basic

addressable element in many computer architectures .
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The size of the byte has historically been hardware dependent and no definitive standards

exist that mandate the size. The de facto standard of eight bits is a convenient power of

two permitting the values 0 through 255 for one byte. Many types of applications use

variables representable in eight or fewer bits, and processor designers optimize for this

common usage. The popularity of major commercial computing architectures have aided

in the ubiquitous acceptance of the 8-bit size. The term octet was defined to explicitly

denote a sequence of 8 bits because of the ambiguity associated with the term byte.

CENTRAL PROCESSING UNIT (CPU)

This part of the computer that executes program instructions is known as

the processor or Central Processing Unit (CPU). In a microcomputer, the CPU is

based on a single electronic component, the microprocessor chip, within thesystem unit or system cabinet. The system unit also includes circuit boards,

memory chips, ports and other components. A microc omputers system cabinet

will also house disk drives, hard disks, etc., but these are considered separate

from the CPU.

The CPU has two parts The Control Unit (CU) and the Arithmetic Logic Unit

(ALU). In a microcomputer, both are on a single microprocessor chip.

Control Unit (CU)

The control unit tells the rest of the computer system how to carry out a

programs

instructions. It directs the movement of electronic signals between memory -

which temporarily holds data, instructions and processes information - and the

ALU. It also directs these control signals between the CPU and input/output

devices.

Arithmetic - Logic Unit (ALU)

Arithmetic Logic Unit, usually called the ALU, performs two types of operations

- arithmetical and logical. Arithmetical operations are the fundamental

mathematical operations consisting of addition, subtraction, multiplication and
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division. Logical operations consist of comparisons. That is two pieces of data

are compared to see whether one is equal to, less than, or greater than the other.

MEMORY

Internal storage areas in the computer. The term memory identifies data storage

that comes in the form of chips, and the word storage is used for memory that exists on

tapes or disks. Moreover, the term memory is usually used as a shorthand for physical

memory, which refers to the actual chips capable of holding data. Some computers also

use virtual memory, which expands physical memory onto a hard disk.

Every computer comes with a certain amount of physical memory, usually

referred to as main memory or RAM . You can think of main memory as an array of boxes,each of which can hold a single byte of information. A computer that has 1 megabyte of

memory, therefore, can hold about 1 million bytes (or characters) of information.

There are several different types of memory:

RAM (random-access memory): This is the same as main memory. When used by

itself, the term RAM refers to read and write memory; that is, you can both write data

into RAM and read data from RAM. This is in contrast to ROM, which permits you onlyto read data. Most RAM is volatile, which means that it requires a steady flow of

electricity to maintain its contents. As soon as the power is turned off, whatever data was

in RAM is lost.

ROM (read -only memory): Computers almost always contain a small amount

of read-only memory that holds instructions for starting up the computer. Unlike

RAM, ROM cannot be written to.

PROM (programmable read-only memory): A PROM is a memory chip on

which you can store a program. But once the PROM has been used, you cannot

wipe it clean and use it to store something else. Like ROMs, PROMs are non-

volatile.
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EPROM (erasable programmable read-only memory): An EPROM is a special

type of PROM that can be erased by exposing it to ultraviolet light.

EEPROM (electrically erasable programmable read-only memory): An

EEPROM is a special type of PROM that can be erased by exposing it to an

electrical charge.
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Unit III

I. IntroductionThe computer will be of no use unless it is able to communicate with the outside World.

Input/Output devices are required for users to communicate with the computer. In simple terms,

input devices bring information INTO the computer and output devices bring information OUT of

a computer system. These input/output devices are also known as peripherals since they surround

the CPU and memory of a computer system.

Some commonly used Input/Output devices are listed in table below.

Input Devices Output Devices

Input device Output devices

Keyboard

Mouse

Joystick

Scanner

Light Pen

Touch Screen

Monitor

LCD

Printer

Plotter

II. INPUT DEVICES

(A) KEYBOARD

It is a text base input device that allows the user to input alphabets, numbers andothercharacters. It

consists of a set of keys mounted on a board.


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Figure 1: The Keyboard

Alphanumeric Keypad

It consists of keys for English alphabets, 0 to 9 numbers, and special characters like +

/ * ( ) etc.

Function Keys

There are twelve function keys labeled F1, F2, F3 F12. The functions assigned tothese keys

differ from one software package to another. These keys are also userprogrammable keys.

Special-function Keys

These keys have special functions assigned to them and can be used only for thosepecific

purposes. Functions of some of the important keys are defined below.

EnterIt is similar to the return key of the typewriter and is used to execute a command orprogram.

Spacebar

It is used to enter a space at the current cursor location.

Backspace

This key is used to move the cursor one position to the left and also delete thecharacter in that

position.

Delete

It is used to delete the character at the cursor position.

Insert

Insert key is used to toggle between insert and overwrite mode during data entry.

Shift

This key is used to type capital letters when pressed along with an alphabet key. Alsoused to type the

special characters located on the upper-side of a key that has twocharacters defined on the same key.

Caps Lock

Cap Lock is used to toggle between the capital lock features. When on, it locks the

alphanumeric keypad for capital letters input only.

Tab


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Tab is used to move the cursor to the next tab position defined in the document. Also,it is used to

insert indentation into a document.

Ctrl

Function Keys

Numeric Keypad

Cursor Movement

Keys

Alphanumeric Keypad/

Special-function Keys

3

Control key is used in conjunction with other keys to provide additional functionality

on the keyboard.Alt

Also like the control key, Alt key is always used in combination with other keys to

perform specific tasks.

Esc

This key is usually used to negate a command. Also used to cancel or abort executing

programs.

Numeric Keypad Numeric keypad is located on the right side of the keyboard and consists of keys

having numbers (0 to 9) and mathematical operators (+ * /) defined on them. This

keypad is provided to support quick entry for numeric data.

Cursor Movement Keys

These are arrow keys and are used to move the cursor in the direction indicated by the

arrow (up, down, left, right).

(b) Mouse

The mouse is a small device used to point to a particular place on the screen and

select in order to perform one or more actions. It can be used to select menu

commands, size windows, start programs etc.

The most conventional kind of mouse has two buttons on top: the left one being used

most frequently.


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Mouse Actions

Left Click : Used to select an item.

Double Click : Used to start a program or open a file.

Right Click : Usually used to display a set of commands.

Drag and Drop : It allows you to select and move an item from one location to

another. To achieve this place the cursor over an item on the screen, click the left

mouse button and while holding the button down move the cursor to where you want

to place the item, and then release it.

Figure 2: The Mouse

(c) Joystick

The joystick is a vertical stick which moves the graphic cursor in a direction the stick

is moved. It typically has a button on top that is used to select the option pointed by

the cursor. Joystick is used as an input device primarily used with video games,training simulators

and controlling robots

The Joystick

(d)Scanner

Scanner is an input device used for direct data entry from the source document intothe computer

system. It converts the document image into digital form so that it canbe fed into the computer.

Capturing information like this reduces the possibility oferrors typically experienced during large

data entry.


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Hand-held scanners are commonly seen in big stores to scan codes and priceinformation for each

of the items. They are also termed the bar code readers.

(e) Bar codes

A bar code is a set of lines of different thicknesses that represent a number. Bar CodeReaders are

used to input data from bar codes. Most products in shops have bar codeson them.Bar code readers

work by shining a beam of light on the lines that make upthe bar code and detecting the amount of

light that is reflected back

(f) Light Pen

It is a pen shaped device used to select objects on a display screen. It is quite like the

mouse (in its functionality) but uses a light pen to move the pointer and select anyobject on the

screen by pointing to the object.Users of Computer Aided Design (CAD) applications commonly

use the light pens todirectly draw on screen.

(g) Touch Screen

It allows the user to operate/make selections by simply touching the display screen.Common

examples of touch screen include information kiosks, and bank ATMs.

(h)Digital camera

A digital camera can store many more pictures than an ordinary camera. Pictures

taken using a digital camera are stored inside its memory and can be transferred to a

computer by connecting the camera to it. A digital camera takes pictures by

converting the light passing through the lens at the front into a digital image.


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The Digital camera

(i) The Speech Input Device

The Microphones - Speech Recognition is a speech Input device. To operate it werequire using a

microphone to talk to the computer. Also we need to add a sound cardto the computer. The Sound

card digitizes audio input into 0/1s .A speech recognitionprogram can process the input and

convert it into machine-recognized commandsor input.

The Microphone

III. OUTPUT DEVICES

(a) Monitor

Monitor is an output device that resembles the television screen and uses a CathodeRay Tube

(CRT) to display information. The monitor is associated with a keyboardfor manual input of

characters and displays the information as it is keyed in. It alsodisplays the program or applicationoutput. Like the television, monitors are alsoavailable in different sizes.

(b) Liquid Crystal Display (LCD)

LCD was introduced in the 1970s and is now applied to display terminals also. Itsadvantages like

low energy consumption, smaller and lighter have paved its way forusage in portable computers

(laptops).


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The LCD

(c) Printer

Printers are used to produce paper (commonly known as hardcopy) output. Based onthe

technology used, they can be classified as Impact or Non-impact printers.Impact printers use the

typewriting printing mechanism wherein a hammer strikesthe paper through a ribbon in order to

produce output. Dot-matrix and Characterprinters fall under this category.

Non-impact printers do not touch the paper while printing. They use chemical, heator

electrical signals to etch the symbols on paper. Inkjet, Deskjet, Laser, Thermal

printers fall under this category of printers.

When we talk about printers we refer to two basic qualities associated with

printers:resolution, and speed. Print resolution is measured in terms of number of dots per

inch (dpi). Print speed is measured in terms of number of characters printed in a unit

of time and is represented as characters-per-second (cps), lines-per-minute (lpm), or

pages-per-minute (ppm).

The Printer

(d) Plotter


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Plotters are used to print graphical output on paper. It interprets computer commandsand makes

line drawings on paper using multicolored automated pens. It is capable ofproducing graphs,

drawings, charts, maps etc.

Computer Aided Engineering (CAE) applications like CAD (Computer AidedDesign) and CAM

(Computer Aided Manufacturing) are typical usage areas forplotters.

:The Plotter(e) Audio Output: Sound Cards and Speakers:

The Audio output is the ability of the computer to output sound. Two components areneeded:

Sound card Plays contents of digitized recordings, Speakers Attached tosound card.

Inputting Text

Inputting text covers the input of text to computer from the page (by sight or optical

character recognition software) or from audio tape. Then the prepared text must be integrated intothe final multimedia product.

Inputting text is not trivial. Rather, it is a subtle and complex process. Sufficient thought

must be given to it in the planning process and in devising procedures which enable all steps

involved in the task to be accomplished effectively and efficiently. Steps frequently include

converting from paper to word-processable files. The text then has to be edited, cut and pasted into

the final program, and reedited to suit each screen layout. This is a skillful, judgemental, labour-

intensive process which can not be automated for the most part.

It is good to agree in advance with any content writer for a project the format in which text

is to be communicated. At worst, it will be a handwritten script. At best, it will be in word-

processable form. It might seem obvious but I think it worth emphasizing that the format for text

communications in a project, even within the design team, should be discussed and agreed by all,


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repeat all , those involved and then it should be documented. Inputting, converting and editing text

can be quite burdensome. It can be difficult for people to keep concentrating on the task in hand,

and the risk of introducing or missing an error is high. Many team members may have an imperfect

grasp of their wordprocessing tools and this can be a problem. Word-processing is often

assumed to be a basic team skill and people are either not inclined to acknowledge a weakness in

this area, do not recognize their weakness here, or are satisfied to live with their bad word-

processing habits. A document laying out a design house style which also underlines the sorts of

problems to be avoided is strongly recommended.

GRAPHICS:

Graphics are visual presentations on some surface, such as a wall, canvas, computer screen, paper,

or stone to brand, inform, illustrate, or entertain. Examples are photographs, drawings, Line Art,

graphs, diagrams, typography, numbers, symbols, geometric designs, maps, engineering drawings,

or other images. Graphics often combine text, illustration, and color. Graphic design may consist

of the deliberate selection, creation, or arrangement of typography alone, as in a brochure, flier,

poster, web site, or book without any other element. Clarity or effective communication may be

the objective, association with other cultural elements may be sought, or merely, the creation of a

distinctive style.

Graphics can be functional or artistic. The latter can be a recorded version, such as a photograph,

or an interpretation by a scientist to highlight essential features, or an artist, in which case the

distinction with imaginary graphics may become blurred.

POINTING DEVICES:

A pointing device is any piece of hardware that is used to allow a user to input spatial data to a

computer. By moving a mouse, pen or a finger around, a user can implement movements and

changes on the computer screen. The most common type of pointing device is the mouse and the

arrow. When the mouse is moved on a mouse pad, the arrow on the screen moves. When the user

clicks down on the mouse, the arrow clicks on the object it is hovering over.
http://en.wikipedia.org/wiki/Visual_systemhttp://en.wikipedia.org/wiki/Canvashttp://en.wikipedia.org/wiki/Brandhttp://en.wikipedia.org/wiki/Photographhttp://en.wikipedia.org/wiki/Drawingshttp://en.wikipedia.org/wiki/Line_Arthttp://en.wikipedia.org/wiki/Graph_of_a_functionhttp://en.wikipedia.org/wiki/Diagramshttp://en.wikipedia.org/wiki/Typographyhttp://en.wikipedia.org/wiki/Numberhttp://en.wikipedia.org/wiki/Symbolshttp://en.wikipedia.org/wiki/Geometrichttp://en.wikipedia.org/wiki/Mapshttp://en.wikipedia.org/wiki/Engineering_drawingshttp://en.wikipedia.org/wiki/Imagehttp://en.wikipedia.org/wiki/Character_%28computer%29http://en.wikipedia.org/wiki/Illustrationhttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Graphic_designhttp://en.wikipedia.org/wiki/Graphic_designhttp://en.wikipedia.org/wiki/Colorhttp://en.wikipedia.org/wiki/Illustrationhttp://en.wikipedia.org/wiki/Character_%28computer%29http://en.wikipedia.org/wiki/Imagehttp://en.wikipedia.org/wiki/Engineering_drawingshttp://en.wikipedia.org/wiki/Mapshttp://en.wikipedia.org/wiki/Geometrichttp://en.wikipedia.org/wiki/Symbolshttp://en.wikipedia.org/wiki/Numberhttp://en.wikipedia.org/wiki/Typographyhttp://en.wikipedia.org/wiki/Diagramshttp://en.wikipedia.org/wiki/Graph_of_a_functionhttp://en.wikipedia.org/wiki/Line_Arthttp://en.wikipedia.org/wiki/Drawingshttp://en.wikipedia.org/wiki/Photographhttp://en.wikipedia.org/wiki/Brandhttp://en.wikipedia.org/wiki/Canvashttp://en.wikipedia.org/wiki/Visual_system


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There are many different types of pointing devices. While the mouse is only one type, it has

become the name of many different types of pointing devices, even if an actual mouse is not used.

TYPES OF POINTING DEVICES

The first types of pointing devices are the ones that require the movement of an object. For

example, a mouse is one of these. Another is a track ball. By moving the mouse or track ball

around, it allows for the arrow on the screen to move. The mouse, though, doesnt need to have a

ball. There are now optical mice that can be used. The general theory about these types of devices

is that by moving, they promote the arrow on the screen to move.

The next category is broader than the former. This is the collection of pointing devices that

rely on touching a surface to create movement on the computer screen. The first type is the touch

screen. In the past, this was not very popular; however, in recent years, this has become

increasingly important. With the iPod, iPad, and other devices available now with touch screen,

this technology is quickly becoming a growing commodity.

The next type is the graphics tablet. This is a tablet that, when using a pen or mouse, a

user can make the arrow move. Instead of being a mouse with a roller ball or optical light, this

relies on the actual table to bring the movement. More specifically, though, is the fact that each

point on one of these tablets represents a point on the monitor. Therefore, if you touch the bottom

right hand corner, the arrow will move to the bottom right hand corner.


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One use of the term display resolution applies to fixed -pixel-array displays such as plasma

display panels (PDPs), liquid crystal displays (LCDs), Digital Light Processing (DLP) projectors,

or similar technologies, and is simply the physical number of columns and rows of pixels creating

the display (e.g., 19201080). A consequence of having a fixed grid display is that, for multi-

format video inputs, all displays need a "scaling engine" (a digital video processor that includes a

memory array) to match the incoming picture format to the display.

Note that the use of the word resolution here is a misnomer, though common. The term display

resolution is usually used to mean pixel dimensions, the number of pixels in each dimension (e.g.,

19201080), which does not tell anything about the resolution of the display on which the image is

actually formed: resolution properly refers to the pixel density, the number of pixels per unit

distance or area, not total number of pixels. In digital measurement, the display resolution would be given in pixels per inch. In analog measurement, if the screen is 10 inches high, then the

horizontal resolution is measured across a square 10 inches wide. This is typically stated as "lines

horizontal resolution, per picture height;" [citation needed ] for example, analog NTSC TVs can typically

display 486 lines of "per picture height" horizontal resolution, which is equivalent to 648 total

lines of actual picture information from left edge to right edge. Which would give NTSC TV a

display resolution of 648486 in actual lines/picture information, but in "per picture height" a

display resolution of 486486.

Current Standards:

Televisions are of the following resolutions:

Standard-definition television (SDTV) :

o 480i (NTSC uses an analog system of 486i split into two interlaced fields of 243

lines)

o 576i (PAL, 720576 split into two interlaced fields of 288 lines)Enhanced-definition television (EDTV) :

o 480p (720480 progressive scan)


High-definition television (HDTV) :
http://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Liquid_crystal_displayhttp://en.wikipedia.org/wiki/Digital_Light_Processinghttp://en.wikipedia.org/wiki/Pixel_densityhttp://en.wikipedia.org/wiki/Pixel_densityhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/NTSChttp://en.wikipedia.org/wiki/Standard-definition_televisionhttp://en.wikipedia.org/wiki/480ihttp://en.wikipedia.org/wiki/NTSChttp://en.wikipedia.org/wiki/Interlaced_videohttp://en.wikipedia.org/wiki/576ihttp://en.wikipedia.org/wiki/PALhttp://en.wikipedia.org/wiki/Enhanced-definition_televisionhttp://en.wikipedia.org/wiki/480phttp://en.wikipedia.org/wiki/Progressive_scanhttp://en.wikipedia.org/wiki/576phttp://en.wikipedia.org/wiki/High-definition_televisionhttp://en.wikipedia.org/wiki/High-definition_televisionhttp://en.wikipedia.org/wiki/576phttp://en.wikipedia.org/wiki/Progressive_scanhttp://en.wikipedia.org/wiki/480phttp://en.wikipedia.org/wiki/Enhanced-definition_televisionhttp://en.wikipedia.org/wiki/PALhttp://en.wikipedia.org/wiki/576ihttp://en.wikipedia.org/wiki/Interlaced_videohttp://en.wikipedia.org/wiki/NTSChttp://en.wikipedia.org/wiki/480ihttp://en.wikipedia.org/wiki/Standard-definition_televisionhttp://en.wikipedia.org/wiki/NTSChttp://en.wikipedia.org/wiki/Wikipedia:Citation_neededhttp://en.wikipedia.org/wiki/Pixel_densityhttp://en.wikipedia.org/wiki/Pixel_densityhttp://en.wikipedia.org/wiki/Digital_Light_Processinghttp://en.wikipedia.org/wiki/Liquid_crystal_displayhttp://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Plasma_displayhttp://en.wikipedia.org/wiki/Plasma_display


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o 1080i (19201080 split into two interlaced fields of 540 lines)


Computer monitors have higher resolutions than most televisions. As of July 2002, 1024768

eXtended Graphics Array was the most common display resolution .[1][2] Many web sites and

multimedia products were re-designed from the previous 800600 format to the higher 1024768-

optimized layout.

The availability of inexpensive LCD monitors has made the 5:4 aspect ratio resolution of

12801024 more popular for desktop usage. Many computer users including CAD users, graphic

artists and video game players run their computers at 16001200 resolution (UXGA, Ultra-

eXtended) or higher if they have the necessary equipment. Other recently available resolutions

include oversize aspects like 14001050 SXGA+ and wide aspects like 1280720 WXGA,

1600768(750) UWXGA, 16801050 WSXGA+, and 19201200 WUXGA. A new more-than-

HD resolution of 25601600 WQXGA was released in 30" LCD monitors in 2007. In 2010, 27"

LCD monitors with the resolution 25601440 were released by multiple manufacturers including

Apple .[3] Special monitors for medical diagnostic work support a resolution of up to 40962160 [4],

which is as of May 2011 the maximum resolution available in a single monitor. The most common

computer display resolutions are as follows :[5]

Resolution % of Intern

Higher than 1 85.1%

1024768 13.8%

800600 0.6%

Lower than 80 0%
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Introdution to Information Technology

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Transcript of Introdution to Information Technology