1 Notes of ICT by Prof. Dr.

SAEED AHMAD Sb

What is ICT?
Information Communication Technology is defined as a tools and resources used to transmit store ,create
,share or exchange information.

History of ICT:
The first commercial computer was the UNIVACI

(Universal Automatic Computer) Developed by John Eckert and John W. Mauchly in 1951.

Claude Shannon was an American mathematics, electrical engineer, computer, he is the father of ICT.

The abbreviation of ICT became popular after it was used in a report to the UK government by Dennis
Stevenson in 1997, And then in the revised National Curriculum for England, Wales and Northern Ireland
in 2000.

Components of ICT:
What are the components of ICT?

 System software, Operating system.

 Input Device, Output Device, Storage Device, Memory Device.

 Hardware, Software, User, NetworkComputer, Internet, LCD Projector.

2 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Examples of ICT

 Computer  Mobile Phone

 Digital Television  Internet
 Robotics  Artificial Intelligence
 Video Conferencing  Online Banking and payment
 Satellite Technology

Uses of ICT:

 Science research  Management aids

 Education  Engineering designing
 Business applications  Road traffic control
 Banking  Railway
 Office Automation  Medicine
 Desktop publishing  Information services

Information and Communication Technologies:

 Information is data that has been sorted and arranged. It consists of organized facts and opinions
people receive during daily life.

 Changing data into information is called data processing or information processing.

 It involves gathering, organizing, and reporting data so it is useful to people.

 It is often done using information technology.

ICT Tools:
 Radio, television, video, DVD, telephone (fixed line & mobile), satellite systems, computer and
network hardware and software; (equipment and services associated with these technologies,
such as videoconferencing and electronic mail.) , blogs

LCD, PC Forums
OHP,
TV/VHS, Whiteboard, Search
Blackboard Phone,
Wireless Phone Interactive Engine,
Pager
Panel Blogs,
e-Groups

Information and Communication Technologies:

 People often use the terms information and communication together.
3 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

 These terms are related, but each means something different.

 Two words we need to know to understand communication technology are data and information.

 Data includes individual facts, statistics (numerical data), and ideas.

 These facts and ideas are not sorted or arranged in any manner.

What is Communication?
 Communication is simply the act of transferring information from one place to another.
 Exchanging Information from computer to another computer

 The classic communication system is made up of an information source, an encoder, a

transmitter, a receiver, a decoder, storage, retrieval, and an information destination.

Synchronous Communication

Online Chat Mobile Technology Satellite

 Text based  Conferencing  Television channel
 Audio besed  Phone  Video
Conferencing
 Video based  Satellite
 Television Channel

Asynchronous Communication
1. Discussion Forums 2. Blogs 3. e-Groups 4. Wikepedia (Knowl base) 5. Google (search engine)
6. Mobile SMS, MMS & Podcasting

Scope of Internet as a ICT in Education

 ICT as a tool to innovate teaching-learning practice via Internet (i.e. digital content, multimedia,
teaching-learning methods, learning environment)

 ICT as an administrative tool (i.e. education management information systems (EMIS)

 ICT as an expanding learning opportunity (i.e. distance learning, e-Learning)

 ICT as a facilitator of higher-order thinking skills (i.e. learner-centered, self-directed learning,

tailored learning)

Traditional v/s Internet based ICT education Approach:

4 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Psychology of using Teaching Aids which include ICTs:

 Hear is an effective saying

 I hear, I forget : Verbal description only are not enough for learners to remember and
understand. Visualization of objects especially in science and technology is important

 I see, I remember: Knowledge that is gained through the site is more colorful, accurate
and permanent. It is said that 80% of our knowledge is gained through our eyes.

ICT can help learning

 Develop understanding

Speed and automatic functions of ICT can enable teachers to demonstrate, explore or explain aspects of
their teaching, and students learning, more effectively e.g. use of a spread sheet to perform calculations
in order that patterns can be concentrated on rather than the calculating.

 Extend access to sources

The capacity and range of ICT can enable teachers and students to gain access to historical, recent or
immediate information, through, for example, accessing information on CD-ROM or the Internet

 Enhance enquiry skills

Search for and compare information from different sources

 Enhance the communication of ideas

Communicate with other people, locally and over distances, easily and effectively present information in
ways which are accessible in different forms for different audiences.
5 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Does ICT increase access to learning opportunity?

 Education opportunities in dispersed locations where conventional schools are not viable;

 A choice to students and parents of what they want to learn i.e. Choice based credit system
(CBCS);

 A safety net for school drop-outs so they do not lapse into illiteracy;

 Alternative venue to schools.

 Second chance education.

 Standardised curriculum materials

 Lifelong learning concept

 Limiting fraud in assessment process

Internet based ICT in Agriculture using web applications

 There are many web sites available for getting information regarding agricultural products.

 One of them is “Soil Health Card” a 12th National e-governance award winner. It reflects soil
testing report (Current composition of soil) and provides information about which crops farmers
should cultivate and which manure should be applied in what proportion.
Agmarknet (Digital Mandi for Indian Kisan –by IIT, Kanpur)
www.kissankerala.net and Many more …

Useful Keys Internet

 Network: Connecting computers with each other For exchanging information

 Client : It is a programme or computer for getting special information from another compute.

 Server: It is a programme or computer, which gives information to the client computer.

 Protocol: It’s a rules for connecting to the internet. (TP/IP)

 Portal: It is a website. Known as a gateway of internet. (Search engine)

 Router: It is a device, which decides where data will be send (Network point)

 www : World Wide Web

 Browser: It is a programme which helps us to use internet

 Website: Group of different web pages.

 URL : Universal Resource Locator

Types of Website (Domain)

.com : Commercial organization
6 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

.net : Large Networks

.gov : Government organization
.org : non-profit making organization
.edu : educational organization
.mil : military organization
.in : India
.au : Australia
.us : United States
.uk : United Kingdom
 7 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Full google:
Google Stand for Global Organization Oriented Group Lanuage of Earth
Google LLC is an American multinational technology company focusing on artificial intelligence, online
advertising, search engine technology, cloud computing, computer software, quantum computing, e-
commerce, and consumer electronics. Wikipedia
Founders: Larry Page, Sergey Brin
Founded: September 4, 1998, Menlo Park, California, United States
Parent organization: Alphabet Inc.
Headquarters: Mountain View, California, United States
CEO: Sundar Pichai (Oct 2, 2015–)
CMO: Lorraine Twohill
Subsidiaries: YouTube, Firebase, Fitbit, Google AI, Google Japan, MORE
what is Google in simple words?

Google is a popular internet search engine. It scans the Web to find Web pages that are relevant to the
words you have typed in the search box.
Components of google
What are examples of components? Sensors, integrated circuits (ICs), capacitors, transistors, and
batteries are examples of components.

What features Google have?

Featured products

 Google Ads.
 Android.
 Chrome.
 Google Cloud.
 Gmail.
 Google Maps.
 Google Photos.
 Google Play

What is computer
What is Computer : Computer is an electronic device that is designed to work with Information.

 An electronic device that can perform the following tasks:

 Respond predictably to input

 Store the set of instructions needed to process the input

 Process the input according to these instructions

 Store the results of processing

8 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

 Output information

The term computer is derived from the Latin term ‘computare’, this means to calculate or programmable
machine. Computer can not do anything without a Program

History of computer:
One of earliest and most well known device was an abacus.Then in 1822,the father of computers what
would be the 1st mechanical computer .and then 1833 he actually designed an Analytical Engine which
was a general purpose computer.

Calculating Machines

3000 BC

 The first calculating device called ABACUS was developed by the Egyptian and Chinese people.

 Its only value is that it aids the memory of the human performing the calculation.

 A skilled abacus operator can work on addition and subtraction problems at the speed of a
person equipped with a hand calculator

 Extract square root and cube root.

 User has to memorize certain rules

Napier’s bones

 English mathematician John Napier built a mechanical device for the purpose of multiplication.

 He invented logarithms, which are a technology that allows multiplication to be performed via
addition.

 The magic ingredient is the logarithm of each operand, which was originally obtained from a
printed table.

 Napier also invented an alternative to tables, where the logarithm values were carved on ivory
sticks which are now called Napier's Bones.

Slide Rule
9 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

 English mathematician Edmund Gunter developed the slide rule. This machine could
perform operations like addition, subtraction, multiplication, and division. It was widely
used in Europe in 16th century.

Pascal's Machine

1642: A Frenchman Blaise Pascal introduced the first mechanical calculating device.

 Pascal invented the Pascaline as an aid for his father who was a tax collector. Pascal built
50 of this gear-driven one-function calculator (it could only add).
 A machine consisted of wheels, gears and cylinders, that could add and subtract .

Difference Engine
 1833: Charles Babbage

• Professor of Mathematics

• Cambridge University

• With Assistance of Lady Augusta Ada Lovelace

 developed a machine that could store information, calculate numbers and solve algebraic
expression.

Babbage’s Analytical Engine

Charles Babbage (father of computer) built a mechanical machine to do complex mathematical

calculations.

Mechanical and Electrical Calculator Mechanical calculator was developed to perform all sorts of
mathematical calculations. Later mechanical calculator was developed to the electrical calculator.

Modern Electronic Calculator

 At first made quite bulky then transistors.

 It can do all kinds of mathematical computations and store some data permanently.

 Its size is too small.

Harvard Mark I

 1944: Howard Aikens and Grace Hooper developed an electromechanical machine at

IBM
 Called Automatic Sequence Controlled Calculator (ASCC)
 Called Mark I by Harvard University
 Capable of reading numbers, characters, and also special symbols
 Built from Switches, Relays, rotating shafts and clutches
10 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

 765,000 components
 Hundred of meters of wires
 Volume
 Length (51ft) X Height (8 ft) x Depth (2 ft)
 Weight 4500 kgs
 Used decimal number systems
Modern Computers:
 Modern computers are digital
 Word “by the numbers”

 Break all types of information into tiny units

 Use numbers to represent information

 Two digits combine to make data (0, 1)

Types of Computers:
Computers Can be divided into the following types on the basis of their working:

1. Analog Computers

2. Digital Computers

3. Hybrid Computers

Analog Computers:
An analog Computer does not operate with digital signals. It recognizes data as a continuous
measurement of a physical property. it has no state. Analog computer is difficult to operate and use.
Voltage ,pressure, speed and temperature are some physical properties that can be measured in this way.

 Analog computer is mainly used in the field of engineering and medicine.

Examples:
1. The speed of the car is measured by speedometer

2. Analog clock measures time by the distance of the hands of a clock around a dial.

Digital Computers:
A Digital Computer Works with Digits. Everything Is described in two states i.e. either on or off. The
number 1 represents on and 0 represents off state. it operates by counting numbers or digits and gives
output in digital form. The digital computers are very fast. These computers store result in digital form.
11 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Examples:
1. Digital watch is a good example of digital computer.

2. Score board that directly count discrete values such as the time left to play and the score of each
team.

Hybrid Computers:
These types of computers are, as the name suggests, a combination of both Analog and Digital computers.
A hybrid computer combines the best characteristics of both the analog and digital computer. It can accept
data in analog and digital form.

Examples:

Hybrid computer devices may calculate patient’s heart function ,temperature, blood pressure etc.

Components of computer:
 These are the 5 major components of a computer that you need to know about:

 Motherboard. ...

 Central Processing Unit (CPU) ...

 Graphical Processing Unit (GPU) ...

 Random Access Memory (RAM

Basic term related computer:

 Vacuum Tube: Vacuum tubes have the functionality of controlling the flow of electronics in a
vacuum. Generally, it is used in switches, amplifiers, radios, televisions, etc.

 Transistor: A transistor helps in controlling the flow of electricity in devices, it works as an

amplifier or a switch.

 Integrated Circuit (IC): Integrated circuits are silicon chips that contain their circuit elements like
transistors, resistors, etc.

 Microprocessors: Microprocessors are the components that contain the CPU and its circuits and
are present in the Integrated Circuit.

 Central Processing Unit (CPU): The CPU is called the brain of the computer. CPU performs
processing and operations work

 Magnetic Drum: Magnetic Drum is like a cylinder that stores data and cylinder.

 Magnetic Core: Magnetic cores are used to store information. These are arrays of small rings.

 Machine Language: Machine Language is the language that a computer accepts (in the form of
binary digits). It is also called low-level programming language.

 Memory: Memory is used to store data, information, and program in a computer.

12 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

 Artificial Intelligence: Artificial Intelligence deals with creating intelligent machines and
behaviors.

Input (Data):
 Input is the raw information entered into a computer from the input devices. It is the collection
of letters, numbers, images etc.

Process:
 Process is the operation of data as per given instruction. It is totally internal process of the
computer system.

Output:
 Output is the processed data given by computer after data processing. Output is also called as
Result. We can save these results in the storage devices for the future use

……………………………………………………………………………………………………………………
Introduction to Internet
What is Internet?

1. A network of networks 2. Internet is a network made of lots of interconnected networks. 3. It

is a wide area network. 4. It is a wonderful and surprising achievement in the field of computer
science. 5. Internet support companies, and just about every type of other organization.

History Of Internet

• APRA NET was created in 1969 and provided the foundation for what come to be know as the
internet.

• The Internet began in 1960, as an experimental four–computer network called ARPA (Advanced
Research Project Agency), which was designed by the U.S Defense Department so that research
scientist could communicate . In approximately two years , ARPA net grew to about two dozen
sites and by 1981, consisted of more than two hundred sites . In 1990, ARPA net was officially
disbanded and the network , which now consisted of hundreds of sites , came to known as the
Internet.

How Internet Works?

• There is no particular organization that controls the Internet.

• Different networks of private companies , government agencies , research organizations ,

universities etc are interconnected together.

• Internet is a huge collection of millions of computer, all linked together on a network.

13 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• Network allows all the computers to communicate with each other.

• A home computers are connected to the internet using phone line modem DSL (Digital Subscribe
Line) or cable modem that communicate to ISP( Internet service providers)

• ISPs then connect to the large ISPs , and the largest ISPs maintain fiber-optic backbones” for
entire region.

• Backbones around the world are connected through the fiber-optic lines, under sea cables or
satellite links.

• In this way every computer on the Internet is connected to every other computer on the
Internet.

• ISP: It is a company that provides the internet connection to the users . There are many ISP
companies in each big cities of each country of the world.

What is Intranet and Extranet

• Intranet: An organization network through which files and messages are exchanged among the
users of an organization only is called the Intranet. This type of network uses the same protocol
as used in the Internet but through the intranet the information can not exchanged outside the
organization.

• Extranet : An extranet is a network of multiple intranets . It means that different companies are
connected together for the collaboration among the companies. On an each extranet each
company connected gives selected rights to employees of one or more other companies to
access its intranet in order to communicate and share information and ideas relevant to that
companies.

Services of Internet
The internet provide a number of services such as :

1. World Wide Web 2. Chatting 3. News Groups 4. Electronic E-mail 5. FTP 6. Electronic E-
Commerce

World Wide Web

1. The World Wide Web is the fastest growing part of the internet. 2. The World Wide Web is a
worldwide information service on the internet. 3. This is a graphical environment that allows the
text and pictures to be displayed on your screen. 4. WWW uses special software called web
Browsers and TCP/IP, HTTP (Hyper Text Transfer Protocol) and a web server to function.

Chatting
• People are talking to other people all around the world.

• They enter to the chat room in order to chat with other people.

• They send messages to each other, discuss ideas and events.

14 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• They are using different services like MSN Messenger and Yahoo Messenger.

News Groups
• News groups are included in internet.

• They can be accessed with the help of your Internet Browsers and enable us to take part in the
discussion of interest with like-minded people from around the world.

Electronic Mail ( E-Mail)

• This service is available over the internet enabling to send and receive the messages on the
global basis.

• People uses e-mail for anything for which they might uses paper mail, faxes , special document
or telephone lines.

• You can communicate globally for the cost of local phone call.

FTP (File Transfer Protocol)

• FTP is simply a way to transfer the files to and from the internet.

• FTP is not just a protocol but also as a service and an application.

• FTP provides the facility to transfer the files between two computers running different operating
system .

• FTP is a service for copying the files from one computer to another computer.

• For two computers to actually make use of the service of FTP , both computers requires a special
application software.FTP is an application for copying files

Electronic E-Commerce

• This is the modern way for selling and buying goods over the internet in a secure manner.

• Credit cards are used for payment.

• Many services are available for handling credit cards over the internet with security.

Addressing Schemes

• The purpose of the internet is to establish a connection between large numbers of computers all
over the world. Computer can send and receive the data to each other.

• On the Internet every computer has a unique address with a reference of this address a computer
can communicate with other computer on the internet. There are two types of addressing
schemes recognized on internet.

IP addressing

DNS addressing
15 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

IP Addressing

• IP stands for internet protocol. • It is a unique identifier for a node on the

Internet.
• It is a numerical address with four • For the internet to function smoothly
numbers separated by dots i-e each machine has a unique IP address.
216.27.16.137.
• The four numbers in the IP address are • A server has a static IP address that does
called octets and have a value between 0 not change.
to 255.
• A home computer that is dialing up through a modem often has an IP address provided by
ISP. That IP is unique for the session but may be different for the next time when machine is
connected.

Domain Type of institution DNS Addressing:

.com Business

.edu Educational institutions

.gov Government organizations

.mil Military organizations

.org Other organizations

• DNS stands for Domain Name System. • The human readable name assigned to
the computer (server) on the Internet is
called Domain name.
• It is common and unique text name. For • The domain “hotmail .com” actually has
example, “hotmail .com” is permanent two parts a host name and top-level
and human readable name. domain(TLD). The top-level domain
represents the institution , which uses
the address . It comes at the end of
domain name separated with dot(.) and
specifies the type of domain .
• It is easier to remember than IP address.

DNS Addressing:

Website Terminologies
16 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

The most important parts of the World Wide Web are the elements such as servers , pages, hot links
and more ,all of which comprises the volume of the WWW . The following are some related terms you
may see:

 Website  Home Page

 Link  HTTP
 Webmaster  Domain Name
 Uniform  Internet
Resource Service
Locator Provider
 Browser  Client
 Hot List

Web Site:

A collection of World Wide Web documents, usually consisting of a home page and several related pages
. You might think of a web site as an attractive electronic book.

Home Page:

Frequently, the “ cover ” of a particular Website . The home page is the main , or the first page displayed
for an organization or person’s World Wide Web site.

Link:

Short for “ hypertext link ” . A link provides the path that connects you from one part of World Wide Web
document to another part of the same document , a different document , or another resource. A link
usually appeared as a uniquely colored word that you can click to be transported to another web page.

HTTP:

Stands for Hyper Text Transfer Protocol. It is a protocol for accessing World Wide Web documents . It is
primary access method for interacting with Internet.

• Stands for Hypertext Transfer Protocol

• Allows computers on the WWW to communicate with one another.

• Handles the “request” sent to the Web server and the “response” received from the Web server.

HTML:

Stands for “ Hyper Text Markup Language ” . HTML is a coding language for the World Wide Web that
informs the web browsers how to display a document text, links , graphics and other media. This language
forms the foundation for all Web pages.

Webmaster:
17 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

The individual responsible for maintaining and updating the content of World Wide document .
Webmaster are the creative forces behind the World Wide Web.

Domain Name:

The portion of the Internet address (URL) following the double forward slashes (//) that identifies an
Internet host site .Domain name are usually two or more terms separated by periods. Some example are
WWW.Isf.com.pk , WWW.Ucp.edu.pk, WWW.microsoft.com .

Uniform Resource Locator(URL):

A URL serves as identification for all the World Wide Web documents . It is an Internet address for locating
Internet elements , such as server sites , documents , files and so on.

• Stands for Uniform Resource Locator

• Also called the Web page’s address

• You typically type it into your Web browser’s location bar when you want to view a Web page

Internet Service Provider(ISP):

ISP is a company that sells computer access to the Internet. A user buys a subscription from Internet
service Provider, which gives the user an identifying name and password and a phone number. With his
or her computer modem , the user calls and connect to and log on to the service provider’s computer. ISP
also supports to high speed dial up access , such as digital subscriber line(DSL) , cable modem or a satellite
, if available in the area.

Browsers:

A software program that request , interprets and presents World Wide Web documents . Frequently
used Web Browsers include Internet Explorer , Netscape Communicator , Mozilla Firefox.

Client:

In addition to being a computer , a client also can be software program that request and acquires
information from computers that store World Wide Web documents and files. World Wide Web Browsers
are also called clients.

Hot list:

An option available in most World Wide Web browsers that maintain a list of frequently accessed home
pages. A hot list also refers to a list of home pages related to the particular subject that is published on an
organization’s home page.

Web Servers and Clients

• A Web server is a computer that is programmed to send files to browsers on other computers
connected to the Internet.

• The Web browser, such as Firefox or Internet Explorer, is the client that sends a request for a Web
page.
18 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• The Web server answers the request and delivers the requested page to the browser so you can
view it.

• Web pages are created using HTML syntax.

• These pages must be organized and stored on central computers.

• Computers which store web pages in the form of directories and files and provide these files to
be read are called “Servers”.

Web Server
The server computer runs special software called “Web Server ” software that allows :

• Web Site management

• Accept Client’s request for information

• Respond to a client’s request by providing the page with required information.

Some of the most popular software , which servers run to allow them to respond to client request for
information , is Internet Information Server (I.I.S), Apache Web Server, Netscape server and Microsoft
Personal web Server.

Web Client OR Web Browsers

Web Clients runs special software called a “Browsers” that allows them to

• Connect to appropriate Server

• Query the server for the information to be read

• Provides an interface to read the information returned by the server.

Some of the most popular Browser software that clients run to allow them to query Web Servers for
information is Netscape Communicator , Internet Explorer.

• To access information stored in the form of Web pages , users must connect to a Web Server.
Once connected , an interface that displays the contents of the Web pages is required.

• Computer that offers the facility to read information stored on web pages is called “Web Client
”.

Web Server-Client Diagram

19 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Surfing the web

• Introduction of different search engines.

• How to Google

• Using operators to make your search better

• Different flavors of Google (scholars, research, images, news, etc.)

Pop server
• In computing, the Post Office Protocol (POP) is an application-layer Internet standard protocol
used by local e-mail clients to retrieve e-mail from a remote server over a TCP/IP connection.[1]
POP and IMAP (Internet Message Access Protocol) are the two most prevalent Internet standard
protocols for e-mail retrieval.[2] Virtually all modern e-mail clients and servers support both. The
POP protocol has been developed through several versions, with version 3 (POP3) being the
current standard

• POP3, sometimes referred to as just "POP," is a simple, standardized method of delivering e-mail
messages. A POP3 mail server receives e-mails and filters them into the appropriate user folders.
When a user connects to the mail server to retrieve his mail, the messages are downloaded from
mail server to the user's hard disk.

Network

What is the definition of a network?

A network is a group of two or more computers or other electronic devices that are interconnected for
the purpose of exchanging data and sharing resources.

What are the uses of network?

20 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

Computer networks enable communication for every business, entertainment, and research purpose.
The internet, online search, email, audio and video sharing, online commerce, live-streaming, and social
networks all exist because of computer networks.

What are the 4 types of networks?

• Personal area network, or PAN.

• Local area network, or LAN.

• Metropolitan area network, or MAN.

• Wide area network, or WAN.

what is the personal area network?

A personal area network (PAN) connects electronic devices within a user's immediate area. The size of a
PAN ranges from a few centimeters to a few meters. One of the most common real-world examples of a
PAN is the connection between a Bluetooth earpiece and a smartphone.

What is a LAN?

A local area network (LAN) is a collection of devices connected together in one physical location, such as
a building, office, or home. A LAN can be small or large, ranging from a home network with one user to
an enterprise network with thousands of users and devices in an office or school.

Regardless of size, a LAN's single defining characteristic is that it connects devices that are in a single,
limited area. In contrast, a wide area network (WAN) or metropolitan area network (MAN) covers larger
geographic areas. Some WANs and MANs connect many LANs together.

What is a metropolitan area network (MAN)?

A metropolitan area network (MAN) is a computer network that connects computers within a
metropolitan area, which could be a single large city, multiple cities and towns, or any given large area
with multiple buildings. A MAN is larger than a local area network (LAN) but smaller than a wide area
network (WAN). MANs do not have to be in urban areas; the term "metropolitan" implies the size of the
network, not the demographics of the area that it serves.

How are MAN networks constructed?

Like WANs, a MAN is made up of interconnected LANs. Because MANs are smaller, they are usually
more efficient than WANs, since data does not have to travel over large distances. MANs typically
combine the networks of multiple organizations, instead of being managed by a single organization.

What is a wide area network (WAN)?

A wide area network (WAN) is a large computer network that connects groups of computers over large
distances. WANs are often used by large businesses to connect their office networks; each office
typically has its own local area network, or LAN, and these LANs connect via a WAN. These long
connections may be formed in several different ways, including leased lines, VPNs, or IP tunnels (see
below).
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The definition of what constitutes a WAN is fairly broad. Technically, any large network that spreads out
over a wide geographic area is a WAN. The Internet itself is considered a WAN.

Ports

Examples of Ports:

• A port is an interface or point of attachment.

• It is used to connect the peripheral devices with the computers such as printers, Keyboards or
mouse.

• Each type of port operates at certain speed.

• The speed is measured in Kilobytes per second or megabytes per second.

Standard Computer Ports

1. Mouse and Keyboard Ports 2. Two USB Ports 3. Serial Port 4. Parallel Port 5. Audio Ports
6. Network Port 7. Modem Port 8. Monitor Port

Standard Computer Ports

• USB Ports: The USB port is one of the most popular and most used ports that come standard on
nearly every computer manufactured today.

 USB stands for "universal serial bus" and serves as a standard for both Windows-based
computers and Apple's Macintosh. USB computer ports typically enable connections with
smaller devices.

 USB is also useful for "plug and play" applications in which a device is connected to the USB
computer port and the driver is automatically located by the operating system, reducing or
eliminating the need for a software boot via disk.
22 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• Audio Ports: The green speaker port is for your headphone or desktop speakers. The pink
microphone port is for a small microphone. The yellow speaker out is designed for home stereo
system.

• Network Port: For internet connection

• Modem Port: It connects your computer to a phone line.

• Monitor Port: Most monitors connect to the three row port on the right side of the image.

Types of Ports:
Different Types of Ports are as follow:

• Serial Ports

• Parallel Ports

Serial Ports

A type of port that transmits one bit at a time is called serial port. It is usually used to connect devices
that do not required fastest data transmission like mouse and keyboard.

Serial port often refer as communication ports. Data travel over the serial port at 115 Kilobytes per
second.

Parallel ports:
• Parallel ports are used to connect the devices that transfer many bits at a time. It usually used to
connect devices that required fast data transmission like printer and scanner.

• Parallel ports are often called as Line Printer ports.

• The speed of Parallel port is 12 Mbps.

• It is faster than serial port.

UART:
• Universal Asynchronous Receiver Transmitter.
• Inside the computer, a chip called UART converts parallel data from the bus into serial
data that flows through a serial cable.
Memory:
• When we receive some instruction or information we retain them in our memory. Similarly a
computer stores the instructions for solving a problem , the data to be processed , the
intermediate results and the final results until they are displayed.

• This storage unit s known as computer memory or store.

• It consists of chips either on the motherboard or on a small circuit board attached to the
motherboard.
23 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• This electronic memory allows the CPU to store and retrieve data quickly.

Types of Memory:
Two types of built-in-memory:

• Permanent memory.

Some memory chips retain the data they hold, even when the computer is turned off. This type of
permanent memory is called nonvolatile.

• Non-Permanent memory.

Other chips – in fact, most of the memory in a microcomputer-lose their contents when the computers
power is shut down. This type of nonpermanent memory is called volatile.

Nonvolatile Memory
• When a computer is turned on, it must know how to start.

• ROM contains a set of start-up instructions called the basic input output system (BIOS) for a
computer.

FLASH MEMORY
• Flash memory is a special type of nonvolatile memory.

• It is often used in portable digital devices for storage.

• Digital cameras, portable MP3 players, USB “keychain” storage devices all use flash memory.

Volatile Memory
• Volatile memory requires to store data.

• The volatile memory in a computer is called random access memory (RAM).

• RAM’s job is to hold programs and data while they are in use.

• Physically, RAM consists of chips on a small circuit board.

• Single inline memory modules (SIMMs) and dual inline memory module (DIMM) chips are found
in desktop computers.

• While the smaller, small outline DIMM (SO-DIMM) chips are found in laptop computers.

RAM
Random Access Memory:
• It is also called main memory or direct access memory or read/write memory.
• A program must be loaded into RAM before execution.
24 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• Data and instructions can be read and modified.

• It play an important role in processing of computer.
Types of RAM
SRAM (Static Random Access Memory)
• Retains contents as long as power is maintained.
• Faster than DRAM.
• SRAM is more expensive.
• CPU does not wait to access data.
• It is usually used to build a very fast memory known as cache.
DRAM (Dynamic RAM)
• Must be constantly refreshed.
• Requires an electric current to maintain its electrical state.
• The electrical charge of DRAM will decrease with time that may result in lose of data.
• Used for most PC memory because of size and cost.

Read Only Memory (ROM)

• Programs and data that are permanently recorded at the factory.

• The instructions can only be read and cannot be deleted.

• Cannot be changed by the user.

• When the computer is switched on ,the instructions in the ROM are automatically loaded into
the memory of the computer.

Types of ROM:
PROM:
• Programmable ROM

• This form of ROM is initially blank.

• The user can write data and programs on it.

• The user can write data and instructions on it only once.

EPROM:
• Stands for Erasable Programmable Read Only Memory
25 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• It is initially blank

• The user can write data and programs on it.

• The data and program written on it can be erased using ultraviolet rays.

EEPROM:
• Stands for Electronically Erasable Programmable Read Only Memory
• It is initially blank
• The user can write data and programs on it.
• The content of EEPROM can be modified easily.
• The data and program written on it can be erased using electrical pulses.

Cache Memory
Small block of very fast temporary memory. Speed up data transfer. It is located inside or close to CPU
chip. It is faster than RAM. Instructions and data used most frequently or most recently.

Step 3
P Transfer to main CPU and cache
R
O
C R
E
S Cache A
S M
O Step 2
R Go to address in main
memory and read
Types of Cache
• Internal cache

– Level 1 (L1)

– Built into microprocessor

26 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

– Up to 128KB or 256 KB

• External cache

– Level 2 (L2)

– Separate chips

– 256KB or 512 KB

– SRAM technology

– Cheaper and slower than L1

– Faster and more expensive than memory

Measuring Storage Capacity

KB – kilobyte GB – gigabyte
• 1024 bytes • Billion bytes
• Some diskettes • Hard disks
• Cache memory • CDs and DVDs

MB – megabyte TB – terabytes
• Million bytes • Trillion bytes
• RAM • Large hard disks

Registers:
• A location used for temporarily hold data or instructions at the moment of execution

• The storage capacity of registers measures in bytes (can be 1,2,4 or 8 bytes registers).

Registers in ALU:
• Accumulator (Acc)

– storing intermediate results of computations

• Status Register (SR)

– to store the status of the result

Registers in CU:
• Program Counter (PC)
– to contain the address of next instruction to be executed

– keep a record of the sequence of execution.

• Instruction Register (IR)

27 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

– to contain instruction that is being executed

• Memory Address Register (MAR)

– to store the address of the data or instruction to be processed

• Memory Data Register (MDR)

– to store data or instruction to be processed.

Registers in CPU:

CPU CU ALU

PC
PSR
MAR
MDR Acc
IR
Microprocessor:
Single Core:
• The single-core has only one processor mounted in a chip that is connected to the motherboard.

• In a single-core or traditional processor the CPU is fed strings of instructions it must order,
execute, then selectively store in its cache for quick retrieval.

• When data outside the cache is required, it is retrieved through the system bus from random
access memory (RAM) or from storage devices.

• Accessing these slows down performance to the maximum speed the bus, RAM or storage
device will allow, which is far slower than the speed of the CPU.

Dual Core:
28 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• A dual-core processor has two microprocessors mounted in one single chip.

• In a dual core processor each core handles incoming data strings simultaneously to improve
efficiency.

• Just as two heads are better than one.

• Now when one is executing the other can be accessing the system bus or executing its own
code.

Benefits of Dual Core:

• Dual-core processors can be highly appreciated in heavy gaming or in intensive data transfers
using a single computer.

• For example, when you are downloading huge files and you are just using a single-core, you
would surely experience lagging of the data transfer. However, dual-cores would not give you
such scenario since the task is divided.

• This makes your time to be used more wisely. It's like falling in line in a store where there are
two cashiers. You would surely pay your goods faster having two cashiers than just having one.

Difference between
Single Core & Dual Core
• Another difference of the single and dual-core processors is the need for multi-
threading software.

• Dual-core processors run with software that can read multi-threading.

• This technology is commonly found in new computers especially in a server

environment that makes data processing really an ease.

Difference Between
Dual Core & Core 2 Duo
• core2duo started before dual core.

• core2duo is under the core2 brand, dual core is under the Pentium brand.

• core2duo limits processor speed to 3.3 GHz, dual core limits it to 2.5 GHz.

• core2duo offers cache size of up to 6MB l2 cache with scope for l3 cache as well, dual core limits
it to around 2 MB.

• Both are based on the core micro architecture.

• core2duo comes for higher prices, and is simply better than dual core.

Difference Between Dual Core & Multiprocessor

• In dual core, resources are shared and the cores reside on the same chip.
29 Notes of ICT by Prof. Dr. SAEED AHMAD Sb

• In multi-processor system, there are two separate CPUs with their own resources.

• A multi-processor system is faster than a system with a dual core processor.

• while a dual core system is faster than a single-core system, all else being equal.

Quad Core:
• Four microprocessors per chip.

• Intel says we can expect a 70 percent performance increase over the

single and double computing cores.

• Intel Launches Three New Quad-core Processors

Multi Core:
A multi-core processor is a processing system composed of two or
more microprocessors.
The largest boost in performance will likely be noticed in improved response time while
running CPU-intensive processes, like antivirus scans or searching for folders.
For example, if the automatic virus scan initiates while a movie is being watched, the
application running the movie is far less likely to be starved of processor power, as the antivirus
program will be assigned to a different processor core than the one running the movie
playback.

Designed & Arranged by:

Muhammad Ishfaq
(CR BS Computer Science) (M)