The word “Internet” stands for International
The information can be sent and received
through internet all over the world.
It connects millions of computers.
Due to internet, our world has become a
How the Internet
Networks of different private
research organizations, and
collectively control the
Internet connects million of
computers together and
allows them to communicate
with each other.
A DSL, phone-line modem or
cable modem can link a
personal computer to the
Our devices connect to ISP,
ISP makes its connection to
larger ISP and then the
The largest ISPs are
“backbone” for an entire
region and they are
connected through fiber
An internal private network of an organization
that can be accessed only by the users of the
organization is called Intranet.
It is a private version of internet.
It uses web technologies for sharing
information and data between the users of
A network of an organization that can be
accessed by authorized outside users is
It is used for business and educational
These users may be customers, suppliers,
business partners etc.
An outside user accesses the username and
1. Web Server
A web server stores web pages or files and
You can also set up your own web server.
The web server software is available to set up
a computer as web server.
The program through which the user gets
information from server as well as sends
information to other user through server is
The personal computer and browser
programs are used to get information from the
The computers that are connected to the
internet and exchange information between
users on the internet are called Hosts.
Host on the internet behaves both as a server
and as a client.
There is no central computer on the internet
but there are millions of hosts computers that
can both send and receive.
4. Web Browser
A program that allows the users to access and
view web pages on the internet is known as Web
browser or Internet browser.
Browsers include the features for sending and
receiving data and files.
The mobile devices, PDAs use a special type of
browser called micro browser, designed for small
5. Internet Protocols
The internet protocols are set of defined rules and
procedure used for communication.
The first protocol was designed in early 1970s for
data communication on network and was named
as Network Control Protocol (NCP).
Some common protocols are:
• TCP/IP- stands for Transmission Control
Protocol or Internet Protocol. This protocol
enables users for data communication on the
• FTP- stands for File Transfer Protocol. This protocol
exchanges files between users.
• HTTP- stands for Hyper Text Transfer Protocol. This
protocol is used for communication between
browsers and web servers.
• SMTP- stands for Simple Mail Transfer Protocol. This
protocol is used to send and receive e-mails on the
• NNTP- stands for Network News Transfer Protocol.
This protocol is used to exchange messages on the
worldwide news bulletin board.
6. Web Page
The documents on the web are called Web
These are electronic documents stored on the
special servers known as web servers.
A web page may contain simple text, images
7. Web Site
A collection of related web pages stored on a
web server is called Website.
The web browser is used to access website.
A website may contain many web pages.
8. Home Page
The main page or title page of a website that
contains the links of other web pages is
referred to as Home page.
A home page is similar to the table of contents
for the websites.
HTML stands for Hyper Text Markup
It is a fundamental language, which is used to
design web pages.
It is easy to write and understand.
Frames are used in a web document to divide
the browser window into different sections.
In each section, a web page can be
11. Web Master
A person who develops and maintains
websites is known as Web master.
Web master and other web developers design
web pages/ website.
12. URL Address
URL stands for Uniform Resource Locator.
It is used by the browser of client computer to
access the documents stored on the host or
Some important URL addresses
13. Addressing Schemes
On the internet, every computer has a unique
address and computers communicate with each
other with references to their addresses.
The addresses are assigned to the computers on
the internet according to some set of rules. These
rules are called Addressing schemes.
There are two types of addressing scheme:
• IP Addressing
• DNS Addressing
• IP Addressing- stands for Internet protocol. It is a
unique identifier for a host or node on the internet. A
typical IP address looks like this: 216. 27. 61. 137.
Every machine on the internet has a unique IP
address. A server has static IP address that does not
• DNS Addressing- stands for Domain Name System.
The human-readable name assigned to the computer
on the internet is called the domain name. The domain
name has two parts, a host name and domain.
The method that allows for creating link of one
section of document to another section or to
another document is called the Hyperlink.
The hyperlink may be created on any text or
ISP stands for Internet Service Provider.
It is a company that provides the internet
connections to the users.
The ISP company provides you, a username for
your identification, a password and a telephone
number to connects its server computer.
The popular ISPs in Pakistan are Comsats, PTCL
and WOL etc.
How to connect to
You must have Internet account of any ISP
company to connect to Internet.
In Pakistan there are many ISP companies
like, PTCL, WOL etc.
Most ISPs have their internet cards available
in local market.
It is very easy and fast way to get internet
account for internet connection.
The following hardware and software are required to
connect to the internet.
• A computer running under Windows operating
system like Windows 2000 and Windows XP.
• A telephone line to connect to the ISP server.
• A modem to exchange information between user’s
computer and server of ISP.
• Web browser for browsing the internet like Internet
• TCP/IP Protocol. The Windows operating system
already includes the TCP/IP.
• Dial up software to establish connection between
your personal computer and server of ISP.
Accessing the Internet
The internet can be accessed through
I. Connecting through Modem.
II. Connecting through LAN.
III. Connecting through High-speed line.
1. Connecting through a
We can connect to the internet through modem.
Most of the individual users connect to the internet
by using a telephone line, a modem of 56 Kbps
and a SLIP (Serial Line Interface Protocol).
When we connect to the ISP’s server computer by
dialing through a telephone number, we have to
give our username, password provided by that
2. Connecting through a LAN
We can connect to the Internet through a
LAN, if LAN uses TCP/IP protocols has an
This type of connection is commonly used by
The computer on the LAN connects to the
internet through a router or modem.
3. Connection through High
The data accessing speed of modem
connection is very slow.
High Speed Lines are available from different
telephone companies, cable TV services etc.
We can access data with very high speed i.e.
20 or more times faster by using fiber optics,
microwaves, satellites etc.
We can share information
with other people around
through internet is very
easy, cheap and a fast
A lot of information of
different types is stored on
the web servers on the
Internet is the most
common source of
The valuable websites can
be damages by hackers
and your valuable data
might be deleted.
There are many security
problems on internet.
We can get latest news of
the world on the internet.
Most of the newspapers of
the world are available on
We can search different
types of jobs all over the
Most of the commercial
organizations advertise their
products through internet.
We can communicate with
other people through
Internet also provides
different types of
entertainment to the people.
Internet provides the facility
to get online education.
Our data on internet can
easily accessed by
Some websites contain
immoral materials in the form
of text, pictures or movies
These websites damage the
character of new generation.
When a keyword is given to
a search engine to search
information, a large number
of related links are
It is difficult to filter out the
A lot of information about
particular topic is stored on
the websites. Some
information may be
incorrect or not authentic.
A lot of time is wasted in
collecting the information
on the internet.
Most of the universities
and education boards
display result on internet,
the students can check
their result in any part of
Many Airline companies
and Pakistan Railway
provide their schedules of
flights and trains, on the
Many websites are also
available on the internet to
get information about
We can consult a panel of
Services Provided by
Internet plays very important role in our society.
It provides a lot of informative information about
business, education etc.
The main services provided by the internet are;
1. World Wide Web (WWW)
8. E-mail (Electronic Mail)
1. World Wide Web
The world wide web is simply referred to as
It is the latest addition to the internet to
It is abbreviated as www or 3w.
It is easiest way to search and to get
information on the internet.
News Groups are discussion groups or forums.
They provide the services to exchange messages
on the internet about a particular subject.
Different newsgroups are available for different
Usually the news client program “Microsoft
Internet News” is used to read and write articles in
FTP stands for File Transfer Protocol.
It is a way of transferring files to others
The files are stored on a special type of
server called the FTP server.
The files from your computer can be uploaded
to the FTP server.
Example of these programs are WS_FTP and
Internet also provide the facility to internet
user to chat with people online all over the
Different programs like MSN Messenger,
Yahoo Messenger, ICQ, AOL online etc. are
available for chatting on internet.
Some chat rooms support voice chats and
E-Commerce stands for Electronic
It is the modern way to run business on
The examples of E-Commerce are; online
shopping, online advertising, online banking
Telnet is an Internet service (or tool) that is
used to login and run commands on a remote
server on the internet.
Through this service, we can also access
information on the internet.
When telnet client program is run on local
computer, we have to give our account name
and password to start the operating session.
Gopher is an internet service.
It organizes resources into multilevel menus
to make finding information easier on the
Before gopher it was difficult to find
information on the internet.
E-mail stands for Electronic mail.
We can send and receive messages
anywhere in the world.
We can also send documents, pictures, audio
and video files via e-mail.
It is also possible to send or receive e-mail
messages through a mobile phone.