Connecting computers usually represented as network.  It is of two types namely Intranet and Internet. When computers connected locally then it is known as intranet and when they are connected globally then they are known as Internet.

            The Internet is a computer network made up of thousands of networks worldwide. No one knows exactly how many computers are connected to the Internet. It is certain, however, that these number in the millions and are growing.  No one is in charge of the Internet. There are organizations which develop technical aspects of this network and set standards for creating applications on it, but no governing body is in control. The Internet backbone, through which Internet traffic flows, is owned by private companies.

            The Internet and the World Wide Web are not synonymous. The Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections etc. whereas the Web is a collection of interconnected documents, linked by hyperlinks and URLs, and is accessible using the Internet.


            First internet access achieved in Advanced Research Projects Agency of US for defence purposes in 29th October 1969 .  It is called as ARPANET due to the name of the Agency.  J.C.R.Licklider, Lawrence Roberts and Paul Baran  played vital role in the development of  that network. 

            The first TCP/IP wide area network was operational by 1 January 1983 , when the United States' National Science Foundation (NSF) constructed a university network backbone that would later become the NSFNet. (This date is held by some to be technically that of the birth of the Internet.) It was then followed by the opening of the network to commercial interests in 1995. Important separate networks that offered gateways into, then later merged into the NSFNet include Usenet, Bitnet and the various commercial and educational X.25 Compuserve and JANET. Telenet (later called Sprintnet), was a large privately-funded national computer network with free dialup access in cities throughout the U.S. that had been in operation since the 1970s. This network eventually merged with the others in the 1990s as the TCP/IP protocol became increasingly popular. The ability of TCP/IP to work over these pre-existing communication networks allowed for a great ease of growth. Use of Internet as a phrase to describe a single global TCP/IP network originated around this time.

The network gained a public face in the 1990s. In August 1991 CERN (Council of European Research in Nuclearphysics), which straddles the border between France and Switzerland publicized the new World Wide Web project, two years after Tim Berners-Lee had begun creating HTML, HTTP and the first few web pages at CERN. In 1993 the National Center for Supercomputing Applications at the University of Illinois at Urbana-Champaign released the Mosaic web browser version 1.0, and by late 1994 there was growing public interest in the previously academic/technical Internet. By 1996 the word "Internet" was common public currency, but it referred almost entirely to the World Wide Web.

Aside from the complex physical connections that make up its infrastructure, the Internet is held together by bi- or multi-lateral commercial contracts and by technical specifications or protocols that describe how to exchange data over the network. Indeed, the Internet is essentially defined by its interconnections and routing policies. As of January 2006, over 1 billion people use the Internet according to Internet World Stats.


Common methods of home access include dial-up, landline broadband (over coaxial cable, fibre optic or copper wires), Wi-Fi, satellite and cell phones.

Public places to use the Internet include libraries and Internet cafes, where computers with Internet connections are available. There are also Internet access points in many public places such as airport halls and coffee shops, in some cases just for brief use while standing. Various terms are used, such as "public Internet kiosk", "public access terminal", and "Web payphone". Many hotels now also have public terminals, though these are usually fee based.

Wi-Fi provides wireless access to computer networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wi-Fi-cafes, where a would-be user needs to bring their own wireless-enabled devices such as a laptop or PDA. These services may be free to all, free to customers only, or fee-based. A hotspot need not be limited to a confined location. The whole campus or park, or even the entire city can be enabled. Grassroots efforts have led to wireless community networks. Commercial WiFi services covering large city areas are in place in London, San Francisco, Philadelphia, Chicago, and other cities, including Toronto by the end of 2006. The Internet can then be accessed from such places as a park bench.

Apart from Wi-Fi, there have been experiments with proprietary mobile wireless networks like Ricochet, various high-speed data services over cellular or mobile phone networks, and fixed wireless services. High end mobile phones such as Symbian smartphones generally come with internet access through the phone network. Web browsers such as Opera are available on these advanced handsets, which can also run a wide variety of other Internet software. More mobile phones have internet access than PCs, though this is not as widely used.


In this context, there are three layers of protocols:

Unlike older communications systems, the Internet protocol suite was deliberately designed to be independent of the underlying physical medium. Any communications network, wired or wireless, that can carry two-way digital data can carry Internet traffic. Thus, Internet packets flow through wired networks like copper wire, coaxial cable, and fibre optic, and through wireless networks like Wi-Fi. Together, all these networks, sharing the same protocols, form the Internet.

The Internet protocols originate from discussions within the Internet Engineering Task Force (IETF) and its working groups, which are open to public participation and review. These committees produce documents that are known as Request for Comments documents (RFCs). Some RFCs are raised to the status of Internet Standard by the IETF process.

Some of the most-used application protocols in the Internet protocol suite are DNS, POP3, IMAP, SMTP, HTTP, HTTPS and FTP. There are many other important ones; see the lists provided in these articles.

All services on the Internet make use of defined application protocols. Of these, e-mail and the World Wide Web are among the most well known, and other services are built upon these, such as mailing lists and blogs. There are many others that are necessary 'behind the scenes' and yet others that serve specialised requirements.

Some application protocols were not created out of the IETF process, but initially as part of proprietary commercial or private experimental systems. They became much more widely used and have now become de facto or actual standards in their own right. Examples of these include IRC chat rooms, and various instant messaging and peer-to-peer file sharing protocols.

            All computers on the Internet communicate with one another using the Transmission Control Protocol/Internet Protocol suite, abbreviated to TCP/IP. Computers on the Internet use client/server architecture. This means that the remote server machine provides files and services to the user's local client machine. Software can be installed on a client computer to take advantage of the latest access technology.


            The World Wide Web is a system of Internet servers that supports hypertext to access several Internet protocols on a single interface. The World Wide Web is often abbreviated as the Web or WWW.  

The World Wide Web was developed in 1989 by Tim Berners-Lee of the European Particle Physics Lab (CERN) in Switzerland. The initial purpose of the Web was to use networked hypertext to facilitate communication among its members, who were located in several countries. Word was soon spread beyond CERN, and a rapid growth in the number of both developers and users ensued. In addition to hypertext, the Web began to incorporate graphics, video, and sound. The use of the Web has reached global proportions and has become a defining aspect of human culture in an amazingly short period of time.

 Almost every protocol type available on the Internet is accessible on the Web. The operation of the Web relies primarily on hypertext as its means of information retrieval.  The World Wide Web consists of files, called pages or Web pages, containing information and links to resources throughout the Internet.

 Web pages can be created by user activity. For example, if you visit a Web search engine and enter keywords on the topic of your choice, a page will be created containing the results of your search. In fact, a growing amount of information found on the Web today is served from databases, creating temporary Web pages "on the fly" in response to user queries.

Access to Web pages may be accomplished by:

  1. Entering an Internet address and retrieving a page directly
  2. Browsing through pages and selecting links to move from one page to another
  3. Searching through subject directories linked to organized collections of Web pages
  4. Entering a search statement at a search engine to retrieve pages on the topic of your choice



The World Wide Web has its own protocol that is HyperText Transfer Protocol or HTTP for its accessing, but it also supports other protocols.  The operation of the Web relies primarily on hypertext as its means of information retrieval. HyperText is a document containing words that connect to other documents. These words are called links and are selectable by the user. A single hypertext document can contain links to many documents. In the context of the Web, words or graphics may serve as links to other documents, images, video, and sound. Links may or may not follow a logical path, as each connection is programmed by the creator of the source document. Overall, the Web contains a complex virtual web of connections among a vast number of documents, graphics, videos, and sounds.

Producing hypertext for the Web is accomplished by creating documents with a language called HyperText Markup Language, or HTML. With HTML, tags are placed within the text to accomplish document formatting, visual features such as font size, italics and bold, and the creation of hypertext links. Graphics and multimedia may also be incorporated into an HTML document.

HTML is an evolving language, with new tags being added as each upgrade of the language is developed and released. For example, visual formatting features are now often separated from the HTML document and placed into Cascading Style Sheets (CSS). This has several advantages, including the fact that an external style sheet can centrally control the formatting of multiple documents. The World Wide Web Consortium (W3C), led by Web founder Tim Berners-Lee, coordinates the efforts of standardizing HTML. The W3C now calls the language XHTML and considers it to be an application of the XML language standard.


Electronic mail, or e-mail, allows computer users locally and worldwide to exchange messages. Each user of e-mail has a mailbox address to which messages are sent. Messages sent through e-mail can arrive within a matter of seconds.  A powerful aspect of e-mail is the option to send electronic files to a person's e-mail address. Non-ASCII files, known as binary files, may be attached to e-mail messages. These files are referred to as MIME attachments. MIME stands for Multimedia Internet Mail Extension, and was developed to help e-mail software handle a variety of file types. For example, a document created in Microsoft Word can be attached to an e-mail message and retrieved by the recipient with the appropriate e-mail program. Many e-mail programs offer the ability to read files written in HTML, which is itself a MIME type.


            Telnet is a program that allows you to log into computers on the Internet and use online databases, library catalogs, chat services, and more. There are no graphics in Telnet sessions, just text. To Telnet to a computer, you must know its address. This can consist of words ( or numbers ( Some services require you to connect to a specific port on the remote computer. In this case, type the port number after the Internet address. Example: telnet 185.  Telnet is available on the World Wide Web. Probably the most common Web-based resources available through Telnet have been library catalogs, though most catalogs have since migrated to the Web. A link to a Telnet resource may look like any other link, but it will launch a Telnet session to make the connection. A Telnet program must be installed on your local computer and configured to your Web browser in order to work.  With the popularity of the Web, Telnet is less frequently used as a means of access to information on the Internet.


            FTP stands for File Transfer Protocol. This is both a program and the method used to transfer files between computers. Anonymous FTP is an option that allows users to transfer files from thousands of host computers on the Internet to their personal computer account. FTP sites contain books, articles, software, games, images, sounds, multimedia, course work, data sets, and more.  If your computer is directly connected to the Internet via an Ethernet cable, you can use one of several PC software programs, such as WS_FTP for Windows, to conduct a file transfer.  FTP transfers can be performed on the World Wide Web without the need for special software. In this case, the Web browser will suffice. Whenever you download software from a Web site to your local machine, you are using FTP. You can also retrieve FTP files via search engines such as FtpFind, located at This option is easiest because you do not need to know FTP program commands.


Chat programs allow users on the Internet to communicate with each other by typing in real time. They are sometimes included as a feature of a Web site, where users can log into the "chat room" to exchange comments and information about the topics addressed on the site. Chat may take other, more wide-ranging forms. For example, America Online is well known for sponsoring a number of topical chat rooms.  Internet Relay Chat (IRC) is a service through which participants can communicate to each other on hundreds of channels. These channels are usually based on specific topics. While many topics are frivolous, substantive conversations are also taking place. To access IRC, you must use an IRC software program.  A variation of chat is the phenomenon of instant messaging. With instant messaging, a user on the Web can contact another user currently logged in and type a conversation. Most famous is America Online's Instant Messenger. ICQ, MSN and Yahoo also offer chat programs. Open Source chat programs include GAIM and Jabber.


            VoIP stands for Voice over IP, where IP refers to the Internet Protocol that underlies all Internet communication. This phenomenon began as an optional two-way voice extension to some of the Instant Messaging systems that took off around the year 2000. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the actual voice traffic, VoIP can be free or cost much less than a normal telephone call, especially over long distances and especially for those with always-on ADSL or DSL Internet connections.  Thus VoIP is maturing into a viable alternative to traditional telephones. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple inexpensive VoIP modems are now available that eliminate the need for a PC.  Voice quality can still vary from call to call but is often equal to and can even exceed that of traditional calls.

Remaining problems for VoIP include emergency telephone number dialing and reliability. Currently a few VoIP providers provide some 911 dialing but it is not universally available. Traditional phones are line powered and operate during a power failure, VoIP does not do so without a backup power source for the electronics.  Most VoIP providers offer unlimited national calling but the direction in VoIP is clearly toward global coverage with unlimited minutes for a low monthly fee


            Webcams can be seen as an even lower-budget extension of this phenomenon. While some webcams can give full frame rate video, the picture is usually either small or updates slowly. Internet users can watch animals around an African waterhole, ships in the Panama Canal, the traffic at a local roundabout or their own premises, live and in real time. Video chat rooms, video conferencing, and remote controllable webcams are also popular. Many uses can be found for personal webcams in and around the home, with and without two-way sound.

            Many existing radio and television broadcasters provide Internet 'feeds' of their live audio and video streams (for example, the BBC). They may also allow time-shift viewing or listening such as Preview, Classic Clips and Listen Again features. These providers have been joined by a range of pure Internet 'broadcasters' who never had on-air licences. This means that an Internet-connected device, such as a computer or something more specific, can be used to access on-line media in much the same way as was previously possible only with a TV or radio receiver. The range of material is much wider, from pornography to highly specialised technical web-casts. Podcasting is a variation on this theme, where—usually audio—material is first downloaded in full and then may be played back on a computer or shifted to a digital audio player to be listened to on the move. These techniques using simple equipment allow anybody, with little censorship or licensing control, to broadcast audio-visual material on a worldwide basis.


            URL stands for Uniform Resource Locator. The URL specifies the Internet address of a file stored on a host computer connected to the Internet. Every file on the Internet, no matter what its access protocol, has a unique URL. Web browsers use the URL to retrieve the file from the host computer and the specific directory in which it resides. This file is downloaded to the user's client computer and displayed on the monitor connected to the machine.  URLs are translated into numeric addresses using the Domain Name System (DNS). The DNS is a worldwide system of servers that stores location pointers to Web sites. The numeric address, called the IP (Internet Protocol) address, is actually the "real" URL. Since numeric strings are difficult for humans to use, alphanumeric addresses are employed by end users. Once the translation is made by the DNS, the browser can contact the Web server and ask for a specific file located on its site.

Anatomy of a URL

This is the format of the URL:  protocol://host/path/filename  For example, this is a URL on the Web site of the U.S. House of Representatives:

This URL is typical of addresses hosted in domains in the United States.
Structure of this URL:

  1. Protocol: http
  2. Host computer name: www
  3. Second-level domain name: house
  4. Top-level domain name: gov
  5. Directory name: house
  6. File name: 2004_House_Calendar_html

Note how much information about the content of the file is present in this well-constructed URL.  Several top-level domains (TLDs) are common in the United States:


commercial enterprise


educational institution


U.S. government entity


U.S. military entity


network access provider


usually nonprofit organizations

New domain names were approved in November 2000 by the Internet Corporation for Assigned Names and Numbers (ICANN): .biz, .museum, .info, .pro (for professionals) .name (for individuals), .aero (for the aerospace industry), and .coop (for cooperatives). ICANN continues to investigate proposals for addding additional domain names, for example, .mobi for sites designed for mobile devices, and .jobs for the human resources community.  In addition, dozens of domain names 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 International Standards Organization as ISO 3166. For example:








United Kingdom

As the technology of the Web evolves, URLs have become more complex. This is especially the case when content is retrieved from databases and served onto Web pages. The resulting URLs can have a variety of elaborate structures, for example,

The first part of this URL looks familiar. What follows are search elements that query the database and determine the order of the results. As a growing number of databases serve content to the Web, these types of URLs will appear more commonly in your browser's address window.


            To access the World Wide Web, Web browser used. A browser is a software program that allows users to access and navigate the World Wide Web. There are two types of browsers:

  1. Graphical: Text, images, audio, and video are retrievable through a graphical software program such as Internet Explorer, Firefox, Netscape, Mozilla and Opera. These browsers are available for Windows, Apple, Linux and other operating systems. Navigation is accomplished by pointing and clicking with a mouse on highlighted words and graphics.  You can install a graphical browser on your computer. For example, Internet Explorer is a part of the Windows operating system, and is also available on the Microsoft site: Firefox available for downloading from and Netscape is available from
  2. Text: Lynx is a browser that provides access to the Web in text-only mode. Navigation is accomplished by highlighting emphasized words in the screen with the arrow up and down keys, and then pressing the forward arrow (or Enter) key to follow the link. In these days of graphical browsers, it may be hard to believe that Lynx was once very popular.

When the browser encounters a sound, image or video file, it hands off the data to other programs, called plug-ins, to run or display the file. Working in conjunction with plug-ins, browsers can offer a seamless multimedia experience. Many plug-ins are available for free.  File formats requiring plug-ins are known as MIME types. MIME stands for Multimedia Internet Mail Extension, and was originally developed to help e-mail software handle a variety of binary (non-ASCII) file attachments. The use of MIME has expanded to the Web. For example, the basic MIME type handled by Web browsers is text/html associated with the file extension .html.  A common plug-in utilized on the Web is the Adobe Acrobat Reader. The Acrobat Reader allows you to view documents created in Adobe's Portable Document Format (PDF). These documents are the MIME type "application/pdf" and are associated with the file extension .pdf. When the Acrobat Reader has been downloaded to your computer, the program will open and display the file requested when you click on a hyperlinked file name with the suffix .pdf. The latest versions of the Acrobat Reader allow for the viewing of documents within the browser window.  Web browsers are often standardized with a small suite of plug-ins, especially for playing multimedia content. Additional plug-ins may be obtained at the browser's Web site, at special download sites on the Web, or from the Web sites of the companies that created the programs.  Once a plug-in is configured to your browser, it will automatically launch when you choose to access a file type that it uses.

            ActiveX is a technology developed by Microsoft which makes plug-ins less necessary. ActiveX offers the opportunity to embed animated objects, data, and computer code on Web pages. A Web browser supporting ActiveX can render most items encountered on a Web page. As just one example, Active X allows you to view and edit PowerPoint presentations directly within your Web browser. ActiveX works best with Microsoft's Internet Explorer.


            When you do what is called "searching the Web," you are NOT searching it directly.  It is not possible to search the WWW directly.  The Web is the totality of the many web pages which reside on computers (called "servers") all over the world.  Your computer cannot find or go to them all directly.  What you are able to do through your computer is access one or more of many intermediate search tools available now. You search a search tool's database or collection of sites -- a relatively small subset of the entire World Wide Web. The search tool provides you with hypertext links with URLs to other pages. You click on these links, and retrieve documents, images, sound, and more from individual servers around the world.  There is no way for anyone to search the entire Web, and any search tool that claims that it offers it all to you is distorting the truth.  At present, we find it useful to describe the kinds of intermediate search tools available to you in four categories.  You use different strategies to find and exploit the potential of the tools in each class:

Types of Search Tools



Search Engines (& Meta-Search Engines)

·         Full-text of selected Web pages

·         Search by keyword, trying to match exactly the words in the pages

·         No browsing, no subject categories

·         Databases compiled by "spiders" (computer-robot programs) with minimal human oversight

·         Search-Engine size: from small and specialized to 90+ percent of the indexable Web

·         Meta-Search Engines quickly and superficially search several individual search engines at once and return results compiled into a sometimes convenient format. Caveat: They only catch about 10% of search results in any of the search engines they visit.

·         Search Engines recommended and described in this tutorial: Google, Alta Vista Advanced Search, Northern Light Power Search, Alltheweb

·         Meta-Search Engines: Metacrawler, Ixquick, Copernic, and others

Subject Directories

·         Human-selected sites picked by editors (sometimes experts in a subject)

·         Often carefully evaluated and kept up to date, but not always -- frequently not if large and general

·         Usually organized into hierarchical subject categories

·         Often annotated with descriptions (not in Yahoo!)

·         Can browse subject categories or search using broad, general terms

·         NO full-text of documents. Searches need to be less specific than in search engines, because you are not matching on the words in the pages you eventually want. In Directories you are searching only the subject categories and descriptions you see in its pages.

·         Recommended and described in this tutorial: Librarians' Index, Infomine, Yahoo!,, AcademicInfo

·         There are thousand more of Subject Directories on practically every topic you can think of.

Specialized Databases (The Invisible Web)

·         The Web provides access through a search box into the contents of a database in a computer somewhere

·         Can be on any topic, can be trivial, commercial, task-specific, or a rich treasure devoted to your topic

·         Locate specialized databases by looking for them in good Subject Directories like the Librarian's Index, Yahoo!, or AcademicInfo; in special guides to searchable databases; and sometimes by keyword searching in general search engines



            There is a five step strategy for searching web.  They are as follows:

1.      Analyze the topic and decide where to begin

2.      Pick up the right starting point

3.      Learn as you go and Vary approach what you learn

4.      Don’t bog down in any strategy that does not work

5.      Return to previous strategies better informed


1.      Find out information from URL itself. (Personal/Domain/Server type)

2.      Scan the perimeter of the page for authority regarding page and link ( Author/ Link providers)

3.      Look for indicators for quality information ( Related links/ update status)

4.      Find out others opinion about the page

5.      Decide yourself with your knowledge


Some governments, such as in Iran and China restrict what people in their countries can access on the Internet, especially political and religious content, through software that filters domains and content, so they may be easily accessed or obtained without elaborate circumvention.

Many countries have enacted laws making the possession or distribution of certain material, such as child pornography, illegal, but do not use filtering software.

There are many free and commercially available software programs with which a user can choose to block offensive Web sites on individual computers or networks, such as to limit a child's access to pornography or violence.


            The Web is a welcoming medium for experimentation and user participation. It is becoming easier to post Web content and share comments with other users. The idea of the Web site is still very much alive, but Web participation is taking new forms and being driven by new technologies that foster social interaction. There are two items considered as latest trends namely Blogs and Rich Site Summary (RSS).  A blog is an easy-to-create Web site that allows users to share their thoughts with the world managed by a lightweight content management system.  RSS allows people to place news and other announcement-type items into a simple XML format that can then be pushed to RSS readers and Web pages.




            Internet found to be used in different fields.  They are as follows:



1. Education: 


            In the field of education, it is used to provide several online books and lecture notes.  Two sites namely NCBI Book Shelf and Online Learning Centre contains many important books.  There is about more than 50 books available at NCBI Book Shelf like Immunology by Kuby, Cell and Molecular Biology by Baltimore, Genetics by Griffith etc., and the main advantage of this site was that it contains full book, heading wise along with figures and tables.  In Online learning Centre, Books published by McGraw Hill company available.  This site provides information like special topics, review questions, animation etc., Lecture Notes can be obtained from Internet for example provides notes in bioinformatic topics.  Even Online Dictionaries available in the sites like and .  Experiments given in the books carried out in the kids special sites like and . Yahoo provides a service known as Yahoo Answers, where a member can post question and answer regarding various fields, which certainly help in improving the knowledge of the students.


2. Research :


            In the case Research, internet provides information in the form of Journals and Research Articles.  In the field of Bioinformatics, internet acts as total source of bioinformatic tools.  Journals provide information regarding research topics and methods.  Even material availability information can also be obtained from Journals.  Site like  provides information regarding more than 350 journals under different category of free after one year of publication, 6 month after publication and some available free right from the date of publication and  site provides different bioinformatic tool list.  NCBI maintains a service known as PubMed which contain research articles for research purposes.



3. Medicine:


            In the field of Medicine, internets provide chances which plays vital role in preserving the life on earth.  For example with the help of internet, Doctors’ can perform Surgery with the help of webcams.  On line Doctor Consultation also help many people to consider specialist on different fields from their native places without taking pain to visit the Doctors’ residence area which is not possible if it is outside India for Indian Nationals who are on or below poverty line.  Even in the field of commercials, Medical Transcription provides many opportunities to undergraduates of life science field.


4. Entertainment:


            This is the one field where most of the people utilizing the internet.  Under Entertainment many field comes namely Movies, Audios, Sports, TV Programmes and Computer Games etc. Many websites like , , and provide information regarding movies both Worldwide and Nationwide.  Many websites like ,, and provide information regarding songs.  In the case of Sports, internet provides information regarding each game separately.  Few of them as follows:,,, and .  In the case games, the following sites like,,, and provide games for both online and offline play.


5. Contacts:


            In this field, internet found to have tremendous advancement as the decades progress.  Initial way of contact developed through internet is electronic mail (E-Mail) service where information can be exchanged within hour which is for better than normal postal mailing.  Later Instant messenger help to exchange information within minutes.  For Instant message transfer, softwares like yahoo messenger, msn messenger needed.  But later voice over internet protocol helped to not only exchange message in words but also help in exchange them along with their own voice.  It provides feeling of sharing information directly.


            But recently, this is further advanced by transferring pictures along with voice and messages over internet with the help of webcams.   This helps people to utilize internet to speak to their relatives who resides in foreign countries.  This mode of conversation is cheaper than normal telephone conversation.  But one of the disadvantages of internet is the availability of the limited number of ports for video transfer method. 



6. Defense:


            Defense, this is the field which actually responsible for the birth of internet, so it can be called as mother field for internet.  This field utilizes internet facility mainly for protection purposes.  It helps for the soldiers to convey information with their head quarters.  Emergency needs can also be communicated through internet.


7. Business:


            In commercial areas like Business too internet plays vital role.  Online shopping becomes fashion in today’s world.  It is used to reduce time and traveling.  Sites like help in online business.  Most of the departmental stores found to have online shopping sites.  Softwares for various purposes can be downloaded from the following sites like,, and  These softwares are of mainly two types namely freeware and shareware/trial/demo versions.  Mostly sharewares/trials/demo versions are available for the business purposes.