The Internet is a worldwide connection of more that 20 million computers and 45,000 networks that follow the Internet protocol (IP). The US Department of Defense Advanced Research Projects Agency (ARPA) invented the Internet in 1969 and called the network ARPANET. The goal was to create a network that would continue to function if a bomb destroyed one or more of the network’s nodes; information gets rerouted automatically so it could still reach its final address. As a result of this bomb-proof design, any user on the Internet can communicate with another user regardless of their location.

In 1970s, universities began using the Internet Protocol to connect their local networks to ARPANET. Access to Pentagon’s computers on the ARPANET was tightly controlled, but university computer were permitted to communicate freely with one another because the software IP was public-domain and joining it became relatively easy.

New users are sometimes confused about when they are on the Internet. Just because you’re connected to another computer does not mean that you’re on the Internet. A lot of computer companies run bulletin-board services (BBS) to which you can connect by running a so-called terminal program; a computer software program that allows you to dial up to a remote computer using a telephone modem. This does not put you on the Internet for 2 reasons:
· The BBS does not use the Internet protocol (IP),
· The BBS is not pat of the Internet; therefore, you’re not connected to the Internet using a dial up to a BBS.

The World Wide Web is a universal information database that not only makes the data be accessible to people around the world, but it also easily link to other pieces of information, so that only the most important data would be quickly found by a user. The WWW project is based on the principle of universal readership: "if information is available, then any (authorized) person should be able to access it from anywhere in the world." The Web's implementation follows a standard client-server model. In this model, a user relies on a program (the client) to connect to a remote machine (the server), where the data is stored.

The Worldwide Web is mostly used on the Internet but they do not mean the same thing. The Web refers to a virtual body of information - an abstract space of knowledge, while the Internet refers to the physical side of the global network, a giant mass of cables and computers.


Internet sources:

Origins of the Internet
The Internet is the word used to describe the massive worldwide network of computers. The word "internet" literally means, "network of networks". In itself, the Internet is comprised of thousands of smaller regional networks scattered throughout the globe. On any given day it connects roughly 15 million users in over 50 countries.

The first recorded description of the social interactions that could be enabled through networking was a series of memos written by J.C.R. Licklider of MIT in August 1962 discussing his "Galactic Network" concept. He envisioned a globally interconnected set of computers through which everyone could quickly access data and programs from any site. In spirit, the concept was very much like the Internet of today. Licklider was the first head of the computer research program at DARPA, 4 starting in October 1962. While at DARPA he convinced his successors at DARPA, Ivan Sutherland, Bob Taylor, and MIT researcher Lawrence G. Roberts, of the importance of this networking concept.

World Wide Web

The World Wide Web (known as "WWW', "Web" or "W3") is the universe of network-accessible information, the embodiment of human knowledge. It is also described as a "wide-area hypermedia information retrieval initiative aiming to give universal access to a large universe of documents"
The World Wide Web began as a networked information project at CERN, where Tim Berners-Lee, now Director of the World Wide Web Consortium [W3C], developed a vision of the project.

The Web has a body of software, and a set of protocols and conventions. Through the use hypertext and multimedia techniques, the web is easy for anyone to roam, browse, and contribute to. An early talk about the Web gives some more background on how the Web was originally conceived.

References:

http://www.isoc.org/internet/history/brief.shtml

http://www.w3.org/WWW/