CLASS IV:
HOW INTERNET IS IMPORTANT?
Internet is termed as network of networks. That means it connects globally any computer to
almost any other computer in the world. And that happens within fraction of seconds.
Time and energy are saved when internet is used for sharing information.
It will help in discussing the beginnings of the Internet to define what the Internet is. Now
you can get as many different definitions of what the Internet is as you can dictionaries. But
for must of us, the simple description, a "worldwide system of interconnected networks and
computers" is pretty good and adequate.
But when people get more technical, they tend to add to the definition terms such
as "a network that uses the Transmission Control Protocol - Internet protocol" (or TCP/IP).
Many people have heard that the Internet began with some military computers in
the Pentagon called Arpanet in 1969. The theory goes on to suggest that the network was
designed to survive a nuclear attack. However, whichever definition of what the Internet is
we use, neither the Pentagon nor 1969 hold up as the time and place the Internet was
invented. A project which began in the Pentagon that year, called Arpanet, gave birth to the
Internet protocols sometime later.
Arpanet was about time-sharing. Time sharing tried to make it possible for research
institutions to use the processing power of other institutions computers when they had large
calculations to do that required more power, or when someone else's facility might do the
job better.
Internet is based on the simple concept that it can connects people. It also makes
sure that information delivered from one place(called “node” ) is properly delivered at
another node.
It also makes sure that the sender can keep track of the sent/received information.
If a fast response is needed in any situation, it can be adopted. If a message is to be
delivered for large audience, it can be beneficially used.
Internet is a nice medium to connect with the entire World.
People use it as a medium to connect with other people, sharing files,
entertainment, information and lots of other activities that are useful and beneficial in many
terms.
Information
People browse internet for information. They love to
browse various search engines like Google, Yahoo to
know about any necessary information. Also people
love browsing websites like Wikipedia which is a
complete encyclopedia on internet.
Social networking
Social networking is an essential medium to
communicate with friend and family
members. There are lots of social networking
websites like Facebook, Orkut, and Bebo
which is heavily consumed by users for
connecting with friends.
Communication
Communication is another way to use
internet.
People connect via each other through
various IM services like Gtalk, Skype, and Yahoo
messenger.
There are lots of other services through
which people send messages.
Transfer of files
From office to schools, from business person to college students everyone send files
through internet. This is an essential part of their life.
These file are send through internet.
People use various mail services like Gmail, Yahoomail, AOL, and Hotmail etc to
send files.
Current buzz
It’s either latest news or Football match score,
people love to surf internet to get a live update of any
news.
Websites like Rediff, NYTimes, Gawker are a quick news providing websites.
Entertainment
There is a very close relation of internet to
entertainment.
It’s watching videos in YouTube, playing live games, or downloading movies;
internet proves its domination everywhere.
Internet Transactions
Now internet can save time and money of
people.
The facility is known as internet banking
facility through which people can deposit any bill,
transfer money through accounts, and make
internet reservations on time from their home.
Making money
People can make money online by using
internet.
People can make money online by many
factual ways. There are lots of options available.
Designing, Freelancing, consultancies, software
providers, application always help people to work
in an easier way.
Marketing
Internet marketers use internet to sell products.
There are lots of social media enthusiasts who promote other’s product online via
various social media sites.
There are lots of publishers available who promote others product by advertising on
various websites blogs etc.
Online education
Online education is very famous medium of study in developed countries and
growing in developing nations.
Various
websites
such
as Khan
Academy and Free Video Lectures offer online
courses to learn various things like designing,
programming, engineering, medical, finance and
other subjects.
This is very helpful medium to promote
education on that place where courses are not
available easily.
Internet is growing with tremendous speed. It became one of the important part of
life. Life without internet cannot be imagined.
HOW INTERNET WORKS
To understand the Internet, it helps to look at it as a system with two main
components.
The first of those components is hardware. That
includes everything from the cables that carry terabits
of information every second to the computer sitting in
front of you.
According to Milton Mueller, a professor of information
studies at Syracuse University, not only is the web not
tubes (or a “web,” really), but it’s actually just a set of
instructions.
“It’s more of a process than a thing,” says Mueller, who teaches, researches and
writes about problems related to global Internet governance. “It’s protocol for breaking
down the data that comes out of your computer into little units called packets.”
Because the Internet is a global network of computers each computer connected to
the Internet must have a unique address.
Internet addresses are in the
form nnn.nnn.nnn.nnn where nnn must be a
number from 0 - 255. This address is known as
an IP address. (IP stands for Internet Protocol;
more on this later.)
The picture below illustrates two
computers connected to the Internet; your
computer with IP address 1.2.3.4 and another
computer with IP address 5.6.7.8.
The Internet is represented as an abstract object in-between.
Diagram 1
If you connect to the Internet through an Internet Service Provider (ISP), you are
usually assigned a temporary IP address for the duration of your dial-in session.
If you connect to the Internet from a local area network (LAN) your computer might
have a permanent IP address or it might obtain a temporary one from a DHCP (Dynamic Host
Configuration Protocol) server.
In any case, if you are connected to the Internet, your computer has a unique IP
address.
Networking Infrastructure
So now you know how packets travel from one computer to another over the
Internet. But what's in-between? What actually makes up the Internet? Let's look at another
diagram:
Here we see diagram with more detail. The physical connection through the phone network
to the Internet Service Provider might have been easy to guess, but beyond that might bear
some explanation.
The ISP maintains a pool of modems for their dial-in customers. This is managed by
some form of computer (usually a dedicated one) which controls data flow from the modem
pool to a backbone or dedicated line router.
This setup may be referred to as a port server, as it 'serves' access to the network.
Billing and usage information is usually collected here as well.
WHAT IS URL? HOW IT WORKS?
Web sites are found by their addresses on the World Wide Web. These addresses
are known as URLs, or Uniform Resource Locators.
Every web site has a URL assigned to it, so both searchers and Web servers can find
them quickly and easily.
The Parts of a URL

http://websearch.about.com/od/dailywebsearchtips/qt/dnt0526.htm is our example.

http://:

domain name: The domain name is the textual representation of the IP address, used to
identify a specific Web page or pages, and comes after the "://".
For example, one of the IP addresses assigned to Facebook is
69.63.176.13; conversely, the domain name for Facebook's IP address is
facebook.com. Every domain name has a top level domain.
These are simple suffixes attached to the end of the domain name that
indicates its place in the domain name hierarchy. Common top level domains
are .com, org, .net, and .gov.

forward slash, then file name: path or directory on the computer to this file; which in our
case is "od/dailywebsearchtips/qt". Think of a file cabinet, with folders assigned
to specific topics, projects, or information.
This identifying information is simply locating where these files can
be found on the Web server, then displaying them for the end user.

name of file: name of file, usually ending in .html or .htm.
The file name for this file is "dnt0526"; moving backwards
through the URL we can deduce that the file lies in sub-directories called "qt",
"daily web search tips", and "od", is on the domain name
"websearch.about.com", and is being delivered to us by the HTTP protocol.
"HTTP" stands for Hypertext Transfer (or Transport) Protocol, and is the
identification technology used to communicate between Web servers and the
users who access their information.
In some URLs, you might see "HTTPS", which
stands for "Hyper Text Transfer Protocol", a secure technology developed to
keep sensitive transactions and information safe online.
This first part of the URL indicates what protocol the URL will be using in
order to deliver the information from the server to the user, and is in front of
the domain name, separated by the "://".
A URL is also known as a Web address.
LAB EXERCISES:
1. OPEN ANY FAVOURITE WEB SITE.
2. OPEN ANY ONE WEB SITE FROM WHERE YOU CAN PURCHAGE ITEMS.
3. IDENTIFY AND EXPLAIN PARTS OF URL.
4. OPEN ANY ONE WEBSITE WHERE YOU CAN GET PICTURES OF ANIMALS.
5. OPEN ANY WEB SITE WHERE YOU CAN KNOW ABOUT INDIAN HISTORY.