ICT teacher handbook/What is internet and web

Internet

If you want information about some book available in your library, you can connect to the library's computer from home and get the information that you want. There are many such computers in different organisations giving us different types of information. These computers are all connected to one another. This is called the Internet. So, for sharing or getting information from another computer on the Internet, you need a connection to the Internet. The Internet is a physical network of millions of computers across the world, each of which has a unique identifier. Some of these computers act as 'servers', they store data which can be accessed by other computers. The millions of computers which are part of the Internet, is like a huge library with information on almost any issue. These computers communicate or share data with one another using the protocol called the TCP-IP, (transmission control protocol/internet protocol). As the name suggests, TCP/IP is the combination of TCP and IP protocols working together. Under TCP/IP each file being transported across the Internet is broken into smaller parts called "packets" by the server. Each packet is assigned an IP (Internet protocol) address of the computer it has to travel to. As the packet moves through the global network it is "switched" by a number of servers toward its destination, the requesting computer or "client" computer. These packets do not usually travel together on the Internet. Packets from the same file may travel via different paths through different servers, but toward the same destination. This “splitting into packets” technology allows us to use Internet most efficiently. It means parts of a file can be shared across a number of phone lines instead of having to find one phone line to put a large file into. It is also hard to break the network, as the data will be routed around the trouble spot. In this respect TCP/IP can be likened to a group of cars which need to go to the same destination, but instead of all of them going on one road (which may be busy), each car can select a different road out of thousands of roads available (thus picking the roads with least traffic), hence all cars can reach the destination in overall least time. The TCP/IP protocol, which is the heart of the Internet was invented by Vincent Van Cerf, Robert Kahn and Louis Pouzin.

World wide web

Web is an application on the Internet (www). This was invented by Tim Berners Lee, to allow computers to access the Internet in the form of a web page, using an application called the Web Browser. There are millions of pages of shared information on the computers in the network, created by many people and organizations, in the form of 'web pages' accessed using a software application called a 'web browser'. This information network is called the World Wide Web. The source of information is called the web site. A web site is a collection of related web pages of information. Initially this was only for downloading, and this was called Web 1.0; when more people wanted to create their own materials and publish on the Internet, the second generation of www was evolved, called Web 2.0. We have moved further along now to collaborative creation of web pages, through online collaboration platforms. Now more and more processing can be done on the Internet, where the data, results and analysis is stored the Internet and we can operate/ add/ access through various web based applications. This is called Cloud Computing.