 BY RAKESH RANJAN KUMAR  MANDEEP HARODE

 The Internet was the result of some visionary thinking by people in the early 1960s who saw great potential value in allowing computers to share information on research and development in scientific and military fields. J.C.R. Licklider of MIT, first proposed a global network of computers in 1962, and moved over to the Defense Advanced Research Projects Agency (DARPA) in late 1962 to head the work to develop it. Leonard Kleinrock of MIT and later UCLA developed the theory of packet switching, which was to form the basis of Internet connections. Lawrence Roberts of MIT connected a Massachusetts computer with a California computer in 1965 over dial-up telephone lines. It showed the feasibility of wide area networking, but also showed that the telephone line's circuit switching was inadequate. Kleinrock's packet switching theory was confirmed. Roberts moved over to DARPA in 1966 and developed his plan for ARPANET. These visionaries and many more left unnamed here are the real founders of the Internet.

 When Senator Ted Kennedy heard in 1968 that the pioneering Massachusetts company BBN had won the ARPA contract for an "interface message processor (IMP)," he sent a congratulatory telegram to BBN for their ecumenical spirit in winning the "interfaith message processor" contract.  Charley Kline at UCLA sent the first packets on ARPANet as he tried to connect to Stanford Research Institute on Oct 29, The system crashed as he reached the G in LOGIN.  Ethernet, a protocol for many local networks, appeared in 1974, an outgrowth of Harvard student Bob Metcalfe's dissertation on "Packet Networks." The dissertation was initially rejected by the University for not being analytical enough. It later won acceptance when he added some more equations to it.

INTRODUCTION  The term internet today refers to the network of public computers running internet protocols.  The internet is a global system of interconnec-ted computer network interchange data by packet switching using the standardized internet protocols(TCP/IP).  It is a network of networks that consists of millions of private and public academic, business and government networks of local to global scope that are linked by coppers wire fibre optic cables wireless connection and other technologies.  The internet carries various information sources such as mail, online chat, file transfer $ file sharing online gaming and interlinked hypertext documents and other sources of world wide web(www).

 INFORMATION:- Information is probably the biggest advantage internet is offering. The Internet is a virtual treasure trove of information. Any kind of information on any topic under the sun is available on the Internet. The search engines like Google, yahoo is at your service on the Internet. You can almost find any type of data on almost any kind of subject that you are looking for. There is a huge amount of information available on the internet for just about every subject known to man, ranging from government law and services, trade fairs and conferences, market information, new ideas and technical support, the list is end less.

 Entertainment is another popular raison d'être why many people prefer to surf the Internet. In fact, media of internet has become quite successful in trapping multifaceted entertainment factor. Downloading games, visiting chat rooms or just surfing the Web are some of the uses people have discovered. There are numerous games that may be downloaded from the Internet for free. The industry of online gaming has tasted dramatic and phenomenal attention by game lovers. Chat rooms are popular because users can meet new and interesting people. In fact, the Internet has been successfully used by people to find life long partners. When people surf the Web, there are numerous things that can be found. Music, hobbies, news and more can be found and shared on the Internet.

 The foremost target of internet has always been the communication. And internet has excelled beyond the expectations.Still; innovations are going on to make it faster, more reliable. By the advent of computer’s Internet, our earth has reduced and has attained the form of a global village. Now we can communicate in a fraction of second with a person who is sitting in the other part of the world. Today for better communication, we can avail the facilities of e- mail; we can chat for hours with our loved ones. There are plenty messenger services in offering. With help of such services, it has become very easy to establish a kind of global friendship where you can share your thoughts, can explore other cultures of different ethnicity.

 E-Commerce:- Ecommerce is the concept used for any type of commercial maneuvering, or business deals that involves the transfer of information across the globe via Internet. It has become a phenomenon associated with any kind of shopping, almost anything. You name it and Ecommerce with its giant tentacles engulfing every single product and service will make you available at your door steps. It has got a real amazing and wide range of products from household needs, technology to entertainment. Services:- Many services are now provided on the internet such as online banking, job seeking, purchasing tickets for your favorite movies, guidance services on array of topics engulfing the every aspect of life, and hotel reservations. Often these services are not available off-line and can cost you more.

 Theft of Personal information:- If you use the Internet, you may be facing grave danger as your personal information such as name, address, credit card number etc. can be accessed by other culprits to make your problems worse. Spamming:- Spamming refers to sending unwanted s in bulk, which provide no purpose and needlessly obstruct the entire system. Such illegal activities can be very frustrating for you, and so instead of just ignoring it, you should make an effort to try and stop these activities so that using the Internet can become that much safer

 TO FIND INFORMATION:- We can use the Internet to find information about almost anything, using Internet search engines such as Google and Yahoo. However, we must carefully check the source (website) and quality of the information. An example of good source of general information is wikipedia.org  FILE SHARING:- A file can be put on a “Shared Location” or onto a File Server for instant use by colleagues. Mirror servers and peer-to-peer networks can be used to ease the load of data transfer.  REMOTE ACCESS:- Computer users can easily connect to other computers and information stores around the world using the internet. The access can be done with or without security, authentication and encryption, depending on the needs.

 Communication and Social Networking:-  Internet chat and instant messaging systems allow people to stay in touch in a convenient way while working at their computers. Messages can be sent and received instantly. In addition, these systems also allow file transfer, as well as voice and video contact.  Social networking websites allow people to stay in touch with friends and family, and knowing their activities by viewing their profiles. The concept of a social networking website is to store people’s profiles and connecting them between one and another. A personal profile can include pictures and videos to be shared  VoIP:-  VoIP (Voice over Internet Protocol) started from an optional two- way voice chat provided by some of the instant messaging systems that started around the year The benefit of VoIP is that it can be free or cost much less than a normal telephone call, because the Internet carries that voice traffic. VoIP is surely a cheap solution for long distance call.

 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  This address is known as an IP address.

 The picture above illustrates two computers connected to the Internet; your computer with IP address and another computer with IP address The Internet is represented as an abstract object in-between.

NETWORKING INFRASTRUCTURING packets travel from one computer to another over the Internet.

Above we see the IP addresses of the sending and receiving computers in the IP header. Below is what a packet looks like after passing through the application layer, TCP layer, and IP layer. The application layer data is segmented in the TCP layer, the TCP header is added, the packet continues to the IP layer, the IP header is added, and then the packet is transmitted across the Internet.