How to Explore the Internet on Your PC

In 1969, the Department of Defense (DOD) of the United States of America started a network called APR net (Advanced Research Project Administration Network). It began in a modest way with one computer in California and three in Utah. Later, to share the software and hardware resources, the military allowed universities to join the network, from where the students caught up with it and developed much of the software, giving birth to the now so very popular Internet.

Note : A network is a group of computers and other devices, such as printers and scanners, connected by a communications link , enabling all the devices to internet with each other. Networks can be small or large, permanently connected through wires or cables, or temporarily connected through phone lines or wireless transmissions.

What is Internet?

Internet is an inter-connection between several computers of different types belonging to various networks all over the globe. It is a network of networks.

The kind of colossal powers that the Internet gives your machine is mind-boggling. To send receive data within a matter of seconds to someone placed beyond the Pacific was unthinkable before the advent of the Internet. The internet represents the transformation and evolution of the entire information age. It is due to these factors that people all over the globe have recognized the Internet as their latest developmental tool. The Internet unleashes the power to communicate unlike any other modality. The Internet is making a major impact on the information technology industry. Major companies like Microsoft, AT&T, Intel and IBM have reworked their business strategies vis-à-vis the Internet.

Advantages of Internet

The Internet is an ocean of information accessible to people across the world, but the way it can be put to use on various platforms is different. The internet simultaneously works as the following.

•  Network--- Organizations can use the Internet to link their offices and employees, turning the Internet into a virtual private network.

•  Medium--- The Internet serves as a communication channel for anybody dealing with product marketing to corporate communications.

•    Market--- The Internet is a vast virtual market place where you can advertise and even order products from the market.

• Transaction Platform--- The Internet allows you to complete your business transactions in the market place. For example, you can complete your financial transactions online while linked directly to your suppliers, customers or financial institutions.

Functionality of Internet

The Internet is and information super-highway and has compressed the world into a cyber colony. Although, there is a major diversity among the Internet community, some shared values have been evolved in the past 25 years of its existence. Though there are no set rules for managing and accessing data over the Internet, a society called the Internet Society (ISOC) exists and works towards bringing order and direction to such a vast undertaking.

The Internet has more than a million computers attached to it, from which arises the need of a proper addressing system for communicating.

This system of addressing is called the Internet Protocal (IP) addressing system. Each computer on the network is called a host, and has a name and a number, which identifies it. The IP addressing system uses:

• The Letter Addressing System

• The Number Addressing System

Letter Addressing System

An example of a letter address is downwind.srrl.umich.edu, which is the address of the University of Michigan Weather Underground and gives free and comprehensive weather forecasting. The last three letters of the address are important because they provide information about the kind of organization to which the address belongs. Some of the abbreviations used are listed below.

Abbreviations	Represents
edu	Educational institutions
mil	Military sites
gov	Government deponents
net	Networking organizations
com	Commercial organizations
Int	International organizations
org	Professional societies

The letter addressing system also users country codes comprising two letters. Examples of country codes are in  for India, ca for Canada and au for Australia. This letter addressing system is called Domain Naming System (DNS).

Number Addressing System

A numeric address has four parts and is referred to as a dotted quad, for example, 41.212.196.197. This is also known as an IP address. Each number in the dotted quad, called an octet, cannot exceed 255. The lettered IP address is mapped to the dotted quad before a machine is accessed. It is recommended that you know the IP address of the host computer you often use.

The Internet, being a packet switching network, transmits data by converting it into small packets. The software document to another that may be located on different machines. The user can use the browser software, such as Internet Explorer, Mosaic or Netscape Navigator to navigate the Web.

that is responsible for marking the Internet function efficiently is the Transmission Control Protocol/Internet Protocol or TIC/IP.

The World Wide Web (WWW)

The Internet application that is currently drawing most attention is the World Wide Web. WWW is a series of servers that are interconnected through hypertext links.

Hypertext is a method of presenting information in a document in which certain text is highlighted and, when selected, displays more information on the particular topic. These highlighted items are called hyperlinks, which allow users to navigate from one document to another that may be located on different machines. The user can use the browser software, such as Internet Explorer, Mosaic or Netscape Navigator to navigate the Web.

A browser is software that helps the user to navigate the WWW. The content and graphics that are displayed on a browser are contained in a Web page. Web pages can contain pictures, buttons and even links to sound files, in addition to text, thus enabling multimedia applications to be displayed on a browser. The term home page commonly refers to the index page of any organization or information source. From the home page, the user can have links that take the user to further levels of information within the some topic, or there can be links to other home pages. Several Web pages together make a Web site.

Common Terminologies

Some of the most commonly used terminologies related to the WWW are:

• Browser--- is client software that allows the user to display and interact with a hypertext document.

• Web server--- is a place where page reside. It is a program that responds to requests from Web browsers to retrieve resources. It is also used to refer to the computer that runs the server programs.

• Home page--- is the first hypertext document displayed when the user follows a link to web server.

• Hypertext Markup Language (HTML)--- is the encoding scheme used to create a Web document.

• Hypertext Transfer Protocol (HTTP)--- is a protocol used on the Web to transfer hypertext documents. A protocol is a set of rules that the computers user to communicate logically.

• Uniform Resource Locator (URL) – is a web addressing scheme that spells out the exact location of an Internet resource. When the user clicks on a link, the browser reads the path of the linked document. The information about the link is provided to the browser by the URL. Any link from one document to another is always implemented by using a URL. AURL contains information about the location of the document. A URL   may point to another HTML document or an image. Certain conventions have to be followed while writhing a URL. A typical URL would be as follows. Certain conventions have to be followed while writing a URL. A typical URL would be as follows:

scheme://host.domain/path/dataname

The following table contains and explanation of the components of a URL:

Component	Description
Scheme	Type of data to which the URL points
host.domain	Refers to the server on which the data is stored
path/dataname	Refers to the location on the server where the data is stored

The URL used on the WWW  to retrieve HTML documents is called HTTP URL. From example, if a file called mtv.html has to be accessed from the directory/lib, on the HTTP web server www.cnn.com, the URL would be:

http://www.cnn.com/lib/mtv.html

An illustration of services provided by the Internet and when to use them is given in the following table:

To	Option
Get a file from another system on the Internet	FTP
Send a file to another system on the Internet	FTP
View files in a directory in a system on another network	Telnet
Correspond with a particular person on the Internet	E-mail or Chat
Correspond with a group of people interested in a similar topic	Newsgroups
Read multimedia documents on the Internet	WWW
Search for everything about a specific topic on the Internet	Gopher

Requirements for Internet Connection

To connect to the Internet, the user needs a computer with a communications software such as Telix, Procom Plus or PCPlus to access the service provider. The hardware requirements to connect to the Internet are:

• A PCAT 486 or higher with SVGA capabilities, if the user intends to use the GUI Brower to navigate the Internet.

• A large capacity hard disk should be available to download the files.

• A modem that can handle at least 9600 bits per second (bps)