Information
Technology
The Internet
Aniqa Amir

Internet
 The word “Internet” stands for International
Network.
 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
“global village”.

How the Internet
works?
 Networks of different private
companies, universities,
research organizations, and
government agencies
collectively control the
internet.
 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
internet.
 Our devices connect to ISP,
ISP makes its connection to
larger ISP and then the
largest ISPs.
 The largest ISPs are
“backbone” for an entire
region and they are
connected through fiber
optics.

The Intranet
 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
same company.

The Extranet
 A network of an organization that can be
accessed by authorized outside users is
called Extranet.
 It is used for business and educational
purpose.
 These users may be customers, suppliers,
business partners etc.
 An outside user accesses the username and
password.

Terminologies & Tool used
for Internet

1. Web Server
 A web server stores web pages or files and
sends information.
 You can also set up your own web server.
 The web server software is available to set up
a computer as web server.

2. Client
 The program through which the user gets
information from server as well as sends
information to other user through server is
called Client.
 The personal computer and browser
programs are used to get information from the
server.

3. Hosts
 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
screens.

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
internet.

• 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
internet.
• 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
Pages.
 These are electronic documents stored on the
special servers known as web servers.
 A web page may contain simple text, images
and hyperlinks.

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.

9. HTML
 HTML stands for Hyper Text Markup
Language.
 It is a fundamental language, which is used to
design web pages.
 It is easy to write and understand.

10. Frame
 Frames are used in a web document to divide
the browser window into different sections.
 In each section, a web page can be
displayed.

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
server.
 Some important URL addresses
• http://www.google.com
• http://www.facebook.com

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
change.
• 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.

14. Hyperlinks
 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
picture.

15. ISP
 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
Internet?
 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.
Hardware:
• 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.
Software:
• Web browser for browsing the internet like Internet
Explorer.
• 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
different ways:
I. Connecting through Modem.
II. Connecting through LAN.
III. Connecting through High-speed line.

1. Connecting through a
Modem
 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
ISP company.

2. Connecting through a LAN
 We can connect to the Internet through a
LAN, if LAN uses TCP/IP protocols has an
internet connection.
 This type of connection is commonly used by
business.
 The computer on the LAN connects to the
internet through a router or modem.

3. Connection through High
Speed Lines
 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.

Internet
Advantages
 We can share information
with other people around
the world.
 Sharing information
through internet is very
easy, cheap and a fast
method.
 A lot of information of
different types is stored on
the web servers on the
internet.
Disadvantages
 Internet is the most
common source of
spreading viruses.
 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
the internet.
 We can search different
types of jobs all over the
world.
 Most of the commercial
organizations advertise their
products through internet.
 We can communicate with
other people through
internet.
 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
unauthorized person.
 Some websites contain
immoral materials in the form
of text, pictures or movies
etc.
 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
displayed.
 It is difficult to filter out the
required information.

 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
country.
 Many Airline companies
and Pakistan Railway
provide their schedules of
flights and trains, on the
internet.
 Many websites are also
available on the internet to
get information about
different diseases.
 We can consult a panel of
online doctors.

Services Provided by
Internet
 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)
2. Newsgroups
3. Chatting
4. FTP
5. E-commerce
6. Telnet
7. Gopher
8. E-mail (Electronic Mail)

1. World Wide Web
 The world wide web is simply referred to as
web.
 It is the latest addition to the internet to
exchange information.
 It is abbreviated as www or 3w.
 It is easiest way to search and to get
information on the internet.

2. Newsgroups
 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
purposes.
 Usually the news client program “Microsoft
Internet News” is used to read and write articles in
the newsgroup.

3. FTP
 FTP stands for File Transfer Protocol.
 It is a way of transferring files to others
through internet.
 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
Cute FTP.

4. Chatting
 Internet also provide the facility to internet
user to chat with people online all over the
world.
 Different programs like MSN Messenger,
Yahoo Messenger, ICQ, AOL online etc. are
available for chatting on internet.
 Some chat rooms support voice chats and
video chats.

5. E-Commerce
 E-Commerce stands for Electronic
Commerce.
 It is the modern way to run business on
international basis.
 The examples of E-Commerce are; online
shopping, online advertising, online banking
etc.

6. Telnet
 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.

7. Gopher
 Gopher is an internet service.
 It organizes resources into multilevel menus
to make finding information easier on the
internet.
 Before gopher it was difficult to find
information on the internet.

8. E-mail
 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.