What exactly is the Internet?

　　The best way to think of the Internet, or Net as it is often called, is as a vast global network of networks connecting computers across the world. These networks range from government departments and industrial and educational communication system down to the personal online service providers such as CompuServe, Delphi, etc.

　　At present, more than 33 million people use the internet and over three million computers worldwide are linked in. They use the Net for transferring data, playing games, socializing with other computer users, and sending e-mail (electronic mail).

　　How did it begin?

　　The Net was dreamt up in the late 1960s by the US Defense Department's Advanced Research Projects Agency which decided that, in the event of a nuclear attack, it needed a means by which messages could be sent and received even if phone lines were inoperative. In 1969, there was a network of just four mainframe computers. By 1972, the number had risen to 40. About this time the idea of the electronic mailbox was born, as users looked for a way of talking to each other electronically. By 1984 when the resources of the network were made available to academics, the Internet began to develop into the form we know it today.

　　The Internet can be divided into five broad areas

　　1. Electronic mail

　　E-mail is much faster than traditional or snail mail because once the message is typed out, it arrives in the electronic mailbox of the recipient within minutes or seconds. Anything that can be digitized—pictures, sound, video—can be sent, retrieved, and printed at the other end. This is efficient, convenient, and saves trees!

　　2. Information sites

　　This is perhaps the fastest growing area of the Internet as more and more people put their own information pages on line. One thing that computers do very well is process vast amounts of information very fast, so, by specifying a key word or phrase, the computer can then search around the Net until it finds some matches. These information sites are usually stored on big computers that exist all over the world. The beauty of the Net is that you can access all of them from your home, using your own PC.

　　3. The World Wide Web

　　The World Wide Web, usually referred to as WWW or 3W, is a vast network of information databases that feature text, visuals, sound, and even video clips. On the WWW you can do such things as go on a tour of a museum or art exhibition, see the latest images from outer space, go shopping, and get travel information on hotels and holidays. You can even view a hotel's facilities before deciding to book!

　　4. Usenet

　　Usenet is a collection of newsgroups covering any topic. Newsgroups allow users to participate in dialogues and conversations by subscribing, free of charge. Each newsgroup consists of messages and information posted by other users. There are more than 10,000 newsgroups and they are popular with universities and businesses.

　　5. Telnet

　　Telnet programmes allow you to use your personal computer to access a powerful mainframe computer. If you are an academic, or just have a lot of number-crunching to do it can be very useful and cost-effective.

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