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Minnesota created Gopher, a simple menu-driven system for accessing files. Internet really became
popular in the 1990s after the development of the World Wide Web (WWW). Before that, it was open
for a handful of sites only. It is amazing that as recently as June 1993, there were only 130 websites, but
now there are millions.
With the growth of Internet, the quality, quantity and variety of information also grew. The Inter-
net today is a repository of every type of information. Nowadays, an Internet user can get all sorts of
information ranging from how to add to the design of a functional spaceship to choosing a product for
personal use.
7. Discuss the basic Internet terminologies used.
Ans: The basic Internet-related terminologies are discussed as follows:
World Wide Web (WWW)
The World Wide Web (abbreviated as Web or WWW) is a collection of linked documents or pages,
stored on millions of computers and distributed across the world. The concept of the Web began at
CERN (the European Center for Nuclear Research) Geneva, Switzerland in the year 1989. Since then,
WWW is the most popularly used Internet sub-network. One of the main reasons that led to its popular-
ity is that it provides information in multimedia form, that is, in more than one medium such as text,
graphics, video and audio. Further, it provides a simple and consistent way of accessing the information
available on the Internet by using hypertext system. In hypertext system, the documents are connected to
other related documents on the Internet through links. The Web uses a specific Internet protocol called
‘HTTP’ to support hypertext documents.
Web Page
The hypertext documents on the World Wide Web are known as ‘web pages’. A web page is written
in a language called ‘HTML’ (Hypertext Markup Language), which enables to embed hypertext links
(discussed later in this section) in the document. Using these hyperlinks, user can jump from one web
page to another.
Website
A website is a set of related web pages (linked through hypertext links), published by an organization
or an individual. Typically, a website contains a home page along with other additional web pages. Each
website is accessed by its own address known as URL (Uniform Resource Locator). All the websites on
the Internet constitute the World Wide Web.
Home page
When you browse the World Wide Web, you will often see the term ‘Home Page’. A ‘home page’ (‘index
page’) is the starting point or a doorway to the website; it refers to the web page that identifies a website
and contains the hyperlinks to other web pages in the website. It may contain links to other websites also.
Like the table of contents of a book, the home page usually provides an overview of what could be found
at the website. If there is not much information, the home page may be the only page of the website.
However, usually you will find at least a few other pages.
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Browser
A browser (short for ‘web browser’) is special software that enables users to read/view web pages and
jump from one web page to another. It is the software that is needed to find, retrieve, view and send
information over the Internet. The most popular browsers are Microsoft Internet Explorer and Netscape
Navigator.
Uniform Resource Locator (URL)
Each web page has a unique address, called a ‘Uniform Resource Locator’ (URL) that identifies its
location on the Internet. Usually, the format of an URL consists of four parts: protocol, name of the web
server (or domain name), path and filename. Here is an example, http://www.xyz.com/tutor/start/main.
htm. The structure of this URL is:
• Protocol: http
• Web Server Name/Domain Name: www.xyz.com
• Path: tutor/start/
• File Name: main.htm
Hypertext
The hypertext is a system that provides a simple and consistent way to organize large data (that includes
text, images, pictures, videos, etc) available on the Internet. In hypertext systems, the documents contain
links to other related documents on the Internet. These links are called ‘hyperlinks’, ‘hotlink’ or simply
‘links’. A hyperlink is used to jump to another part of the same page or to load a different web page.
Usually, hypertext links appear in a different colour (typically in blue and underlined) from the rest of
the text.
Internet Service Provider (ISP)
ISP is an organization that connects its subscribers’ computer using modem to the Internet. The
connections can be provided by telephone lines, cable lines or wireless connections. In order to use the
Internet connection, the user has to first log on to the host computer using the username and password
provided by the ISP. Some of the well-known ISPs are America Online (AOL), Microsoft Network
(MSN), Yahoo! etc.
Web Server
A server is a computer equipped with server software, which provides a specific kind of services to
client software running on other computers. It can refer to a particular piece of software, for example,
a web server or to a machine on which the server software is running. A ‘web server’ receives request
from the clients, processes this request and sends the result back to the client. In other words, web server
fulfils the client’s (browser) requests.
Download and Upload
‘Download’ refers to the act of transmitting data from a remote computer on the Internet or other network
to one’s own computer. When the user downloads a file, he/she is actually copying a particular file from
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the remote computer and placing it on their hard drive. Downloading allows a user to save a file for later
use, thereby reduces the time spent online and the corresponding charges.
Upload is just the opposite of download. ‘Upload’ refers to the act of transmitting data from local com-
puter to any other computer on the Internet or network. For example, a software company may upload a
demonstration of its new software onto the web, so that users can then download the software.
Online and Offline
The term ‘online’ is commonly referred to the state of being connected to the networked computer system
or Internet. For example, if you are browsing the WWW, your computer is said to be online. Being online
also refers to any peripheral device (such as printer) that is connected to the system and ready to use.
‘Offline’ is just the opposite of online; it refers to the state of not being connected to the remote
computer or Internet. A printer or other peripheral that is not ready to use is also considered offline.
8. List some advantages of Internet.
Ans: Internet offers various advantages. Some of them are as follows:
• Information retrieval: The Internet serves as the biggest and a valuable resource of information.
One can find any type of information on any subject with the help of the search engines such as
Yahoo and Google.
• Communication: The primary goal of the Internet is communication. It has done extremely well in
this field; however, the development process is still going on to make it more dependable and quick.
By sending an e-mail, we can contact a person who is physically present thousand miles away
within the fraction of a second’s time.
• Entertainment: Internet functions as a popular medium of entertainment. A wide variety of enter-
tainment including video games, music, movies, chat room, news and others can be accessed
through the Internet.
• E-commerce: It is the idea that is implemented for any form of commercial strategy or busi-
ness transactions that entails the transmission of data from one corner of the world to another.
E-commerce has become a fantastic option through which one can shop anything.
• Formation of communities: Internet helps in the formation of communities or forums. Here, a
number of people can participate in different types of debates and discussions, express their views
and gather valuable knowledge.
• Services: A variety of services are offered via Internet, for example, job searching, online banking,
buying movie tickets, hotel reservations, consultation services etc.
9. Explain the structure of URL.
Ans: Usually, the format of a URL consists of four parts: protocol, server (or domain), path and
filename. For example, http://www.xyz.com/tutor/start/main.htm. The structure of this URL is described
as follows:
• Protocol: http
• World Wide Web: www
• Domain Name: xyz
• Domain Type: com
• Path: tutor/start/
• File Name: main.htm
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The first part of the address, the part before the colon, is the ‘protocol’. Most of the time when you
see http (hypertext transfer protocol), you are accessing a web page. Apart from http, you could also
find other protocols such as ftp (file transfer protocol), news (news server), mailto (mail server, used
for accessing an e-mail server) and telnet (for accessing remote computers). The protocol is separated
by colons and slashes. After the slashes, the ‘World Wide Web’ is indicated by www. Note that it is not
necessary that all the addresses should contain www. Although most Internet addresses include a www,
a web page can reside on the part of the Internet that is not found on the World Wide Web. Next is the
‘domain name’ where the information is located. A domain name is unique and case sensitive human-
readable name for a host on the Internet. After the domain name, the domain type is displayed such as
com. A ‘domain type’ represents the type of organization or country to which the host belongs. A dozens
of domain types have been assigned to identify and locate files stored on host computers in countries
around the world.
These are referred to as two-letter Internet country codes and have been standardized by the Interna-
tional Standards Organization (ISO). For example, uk for the United Kingdom, de for Germany, au for
Australia and in for India. The last part of a URL consists of the path and the file name. ‘Path name’
specifies the hierarchic location of the said file on the computer. For instance, in http://www.xyz.com/
tutor/start/main.htm, the ‘file’ main.htm
is located in start, which is a sub- directory of tutor.
10. Explain how Internet connection can be established?
Ans: The Internet is a bunch of computers linked together through a network, so that computer
users in different locations can have access to the same information. The basic requirements for getting
connected to Internet are described as follows:
A TCP/IP-enabled computer
The computer must have at least 386-microprocessor chip with a minimum of 16 MB of RAM. For a
good browsing experience, use a faster chip (Pentium III/Pentium IV) with more RAM (128/256 MB). In
addition, a colour monitor, with at least 640 × 480 resolution and a capability of displaying a minimum
of 256 colours, is also vital. The system should also possess a hard disk, with at least 200 MB of free
space, to store Internet software and temporary Internet files. Since the web is a multimedia medium,
you can also enjoy sound on your system with a sound card and a pair of speakers.
Modem
Apart from the previously mentioned configuration, a computer system must have a device called
modem, which enables a computer to transmit data over telephone lines. A ‘modem’ (acronym for
modulator-demodulator) is a hardware, which converts digital data into analogue signals (i.e., modu-
lation) that can be sent over an analogue telephone line and convert the analogue signal back into
digital data (that is, demodulation). Thus, when the modem receives the data from a web server
via phone system, it reconstitutes the analogue signal into digital form, so that the computer can
understand it. The most critical aspect of the modem is its speed of operation. The speed of modem
is measured in Kilobits per second (Kbps). Modern modem supports 28-Kbps to 56-Kbps speeds.
Modems are of two types:
(i) Internal Modem: It is a card, which is fitted inside the computer with a lead running directly
from the computer to the phone socket.
(ii) External Modem: It is a small external box wired between the computer and the phone socket.
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Internet Connection
Before connecting to the Internet, you need to buy an Internet connection from an authorized Internet
Service Provider (ISP). The speed of accessing the Internet entirely depends upon the type of connec-
tion you bought from the ISP. Some of connections available for the users these days are discussed in
the next question.
11. Explain various types of Internet access or connections.
Ans: Some of the common types of Internet access, available for the users these days, are as follows:
• Dial-up: A dial-up connection is the access method that uses telephone lines to connect to the
Internet. It is the most common way for individuals who use home computers to connect to the
Internet. To connect to the Internet by using dial up, the user needs to specify a username, a pass-
word and a telephone number. After the connection is established, the user can start browsing sites
on the Internet.
• ISDN: It stands for Integrated Services Digital Network and is more common in business and
commercial uses. It was the first high-speed alternative to regular analog phone modems. ISDN
involves the digitization of telephone network, so that voice, graphics, text and other data can be
provided to users from a single terminal over existing telephone wiring. Digital connections have
fewer errors in transmission, which means speed of downloading graphics, web pages, sound and
so on is increased to four times faster than with dial-up modems.
• Cable Modem: A cable modem connects the user to the Internet through a cable television line.
Nowadays, many cable companies offer Internet along with television accessibility. A cable modem
will typically have two connections, one to the television outlet and the other to the computer.
Cable modems provide not only a faster Internet access (10 to 100 times as fast as the dial-up
modem), but also interactivity to the television.
• Leased Line: This facility provides reliable and high-speed Internet access ranging from 2.4 Kbps
to 45 Mbps. A leased line connection is an affordable way to link two or more sites for a fixed
monthly charge. Usually, leased lines facility can be provided via a fibre-optic or copper line.
Leased line service provides a consistent amount of bandwidth and is an excellent way to provide
data, voice and video links between sites.
• DSL: DSL or Digital Subscriber Line service is provided through an existing phone line, but it
works differently than regular analog modem dial-up access. DSL operates over normal telephone
lines and it can be used simultaneously with the telephone. DSL can increase the connection speed
by as much as ten-fold from a standard dial-up modem.
• Broadband: This type of access is good for remote locations, where ISDN, cable or DSL are
not available. It gives a decent download speed, but to upload data, the user still needs a regular
analog modem to dial in, via a phone line. Satellite connection can be either a two-way service
or a one-way service. In case of two-way satellite service, the data is transmitted via satellite to
a dish antenna at the user’s house. In one-way system, the user needs a conventional modem and
telephone link to an ISP. Satellite connection is expensive but sometimes is the only fast option for
people who are beyond the service area of cable and DSL providers.
12. Briefly explain any three Internet applications or services.
Ans: The Internet has grown from a small project to today’s biggest network of computers. Due to this
colossal growth, the Internet has become the biggest domain of information. Nowadays, an Internet user
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