The Internet is a global network of computer networks, linking together millions of machines from the mightiest mainframe to the humblest home computer. The beginnings of the Internet go back to 1969 when the American Defence Advanced Research Projects Agency (DARPA) began experimenting with building a network to allow scientists to share data that would be robust enough to survive partial outrages, as in a bomb attack. The Internet itself came into being in the mid 80’s when the National Science Foundation funded the building of a communications backbone to connect five regional supercomputing centres so that the nation’s universities could all share their facilities.

Access was then mostly limited to scientists, academic researchers and government employees, and access use policies prohibited commercial traffic across the Internet. It did not take long for similar networks in other countries to start hooking themselves up to the Internet along with other small, independent local networks and dial-up bulletin board systems. By 1994, the Internet was spreading everywhere, fuelled partly by changes to policy to allow the carriage of commercial traffic, partly by the advent of the World Wide Web. By the end of 1997 estimates were that the Internet had 60 million users world - wide.

The Internet itself is a giant computer network. It is run as a co-operative, in that everyone pays for their own connection. For example, a consumer at home dialling into a service provider pays for their telephone connection and Internet account; the service provider in turn pays for it’s connections to other larger provider and the larger provider pays for it’s connections to other large providers with whom it exchanges data. This co-operative nature means that distance is irrelevant on the Internet: a message from London to Bristol costs the same to send as one from London to Sydney.

At heart, what makes the Internet work is a set of common standards known as Internet protocols or TCP/IP (Transmission Control Protocol/Internet Protocol). A computer can connect with the Internet and exchange data as long as it can run those protocols. Running across that infrastructure are services such as the World Wide Web and others. All these services depend on a client /server architecture. A Web site is hosted on a large computer owned by say a company or university and running software that allows it to deliver to Web pages.

When you access that Web site you run complementary client software, known as a browser, which is able to request and receive those pages. There are many other services and applications that run across the Internet, including FTP (File Transfer Protocol), Gopher (menu-based indexes), Usenet (world wide discussion groups) and Internet Relay Chat (for real time chatting) but for most the Internet is e-mail and the Web.

Nicola Corboy