Email is not that different from regular mail, actually: you have a message, an address, and a carrier that figures out to get it from here to there.

The difference is that email messages--and any attachments--are broken down into small chunks of data called packets, which travel independently, weaving their way along with innumerable other packets travelling to different destinations. It's as if each page of a letter was mailed separately. On the way, the packets are passed from one server to the next until they reach their final destination. Any given message's packets and attached file may travel by several different routes, so the components often arrive out of order and at different times. Once all the packets have arrived, they are recombined into their original form.

This makes sending the message faster, because it doesn't require transmitting one big, bandwidth-hogging piece of data. But it also means that an entire message can be held up if one little piece is missing. Usually, however, this entire process, travelling 3,000 miles or more, takes less than a minute to complete.

But what if you don't know a person's email address? It's actually pretty easy to track someone down on the Net. Web sites such as WhoWhere, Four11, and Bigfoot list individual and business email addresses; all you have to do is type in the name. Most search engine sites offer similar features, as do the Netscape Messenger, Microsoft Outlook Express, and Eudora email programs.

If you want to send or receive a mass mailing, you need to subscribe to a mailing list, also known as a listserv. Usenet newsgroups, on the other hand, are publicly stored messages that anyone can look at; you don't have to be a member of a list to read these messages.