Services and Resources of the Internet

A COMMON resource provided by the Internet is a worldwide system for sending and receiving electronic mail, known as E-mail. In fact, E-mail represents a large portion of all Internet traffic and is for many the only Internet resource they use.

How does it work? To answer that question, let's review the ordinary mail system first. Imagine that you live in Canada and wish to send a letter to your daughter living in Paris. After properly addressing the envelope, you mail it, starting the letter's journey. At a postal facility, the letter is routed to the next location, perhaps a regional or national distribution centre, and then to a local post-office near your daughter.

A similar process occurs with E-mail. After your letter is composed on your computer, you must specify an E-mail address that identifies your daughter. Once you send this electronic letter, it travels from your computer, often through a device called a modem, which connects your computer to the Internet via the telephone network. Off it goes, bound for various computers that act like local and national postal routing facilities. They have enough information to get the letter to a destination computer, where your daughter can retrieve it. Unlike the regular mail, E-mail often reaches its destination, even on other continents, in minutes or less unless some part of the network is heavily congested or temporarily out of order. When your daughter inspects her electronic mailbox, she will discover your E-mail. The speed of E-mail and the ease with which it can be sent even to multiple recipients all over the world make it a popular form of communication.

Newsgroups

Another popular service is called Usenet. Usenet offers access to newsgroups for group discussions on specific topics. Some newsgroups focus on buying or selling various consumer items. There are thousands of newsgroups, and once a user has gained access to Usenet, there is no cost to subscribe to them.

Let’s imagine that someone has joined a newsgroup involved in stamp collecting. As new messages about this hobby are sent by others subscribing to this group, the messages become available to this newcomer. This person reviews not only what someone has sent to the newsgroup but also what others have written in response. If, for example, someone requests information about a particular stamp series, shortly afterward there may be many responses from around the world, offering information that would be immediately available to all who subscribe to this newsgroup.

A variation of this idea is the Bulletin Board System (BBS). BBSs are similar to Usenet, except that all files are located on a single computer, usually maintained by one person or group. The content of news-groups reflects the varied interests, viewpoints, and moral values of those who use them, so discretion is needed.

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