All of the millions of people around the world who use the Net have their own e-mail addresses. A growing number of "gateways" tie more and more people to the Net every day. When you logged onto the host system you are now using, it automatically generated an address for you, as well.
The basic concepts behind e-mail parallel those of regular mail. You send mail to people at their particular addresses. In turn, they write to you at your e-mail address. You can subscribe to the electronic equivalent of magazines and newspapers. You might even get electronic junk mail.
E-mail has two distinct advantages over regular mail. The most obvious is speed. Instead of several days, your message can reach the other side of the world in hours, minutes or even seconds (depending on where you drop off your mail and the state of the connections between there and your recipient). The other advantage is that once you master the basics, you'll be able to use e-mail to access databases and file libraries. You'll see how to do this later, along with learning how to transfer program and data files through e-mail.
E-mail also has advantages over the telephone. You send your message when it's convenient for you. Your recipients respond at their convenience. No more telephone tag. And while a phone call across the country or around the world can quickly result in huge phone bills, e-mail lets you exchange vast amounts of mail for only a few pennies -- even if the other person is in New Zealand.
E-mail is your connection to help -- your Net lifeline. The Net can sometimes seem a frustrating place! No matter how hard you try, no matter where you look, you just might not be able to find the answer to whatever is causing you problems. But when you know how to use e-mail, help is often just a few keystrokes away: you can ask your system administrator or a friend for help in an e-mail message.
[section on using Unix mail deleted]
Are there any drawbacks to e-mail? There are a few. One is that people seem more willing to fly off the handle electronically than in person, or over the phone. Maybe it's because it's so easy to hit R and reply to a message without pausing and reflecting a moment. That's why we have smileys! There's no online equivalent yet of a return receipt: chances are your message got to where it's going, but there's no absolute way for you to know for sure unless you get a reply from the other person.
So now you're ready to send e-mail to other people on the Net. Of course, you need somebody's address to send them mail. How do you get it?
Alas, the simplest answer is not what you'd call the most elegant: you call them up on the phone or write them a letter on paper and ask them. Residents of the electronic frontier are only beginning to develop the equivalent of phone books, and the ones that exist today are far from complete.
Eventually, you'll start corresponding with people, which means you'll want to know how to address mail to them. It's vital to know how to do this, because the smallest mistake -- using a comma when you should have used a period, for instance, can bounce the message back to you, undelivered. In this sense, Net addresses are like phone numbers: one wrong digit and you get the wrong person. Fortunately, most net addresses now adhere to a relatively easy-to-understand system.
Earlier, you sent yourself a mail message using just your user-name. This was sort of like making a local phone call -- you didn't have to dial a 1 or an area code. This also works for mail to anybody else who has an account on the same system as you.
Sending mail outside of your system, though, will require the use of the Net equivalent of area codes, called "domains." A basic Net address will look something like this:
tomg@world.std.com
Tomg is somebody's user ID, and he is at (hence the sign) a site (or in Internetese, a "domain") known as `std.com'. Large organizations often have more than one computer linked to the Internet; in this case, the name of the particular machine is world (you will quickly notice that, like boat owners, Internet computer owners always name their machines).
Domains tell you the name of the organization that runs a given e-mail site and what kind of site it is or, if it's not in the U.S., what country it's located in. Large organizations may have more than one computer or gateway tied to the Internet, so you'll often see a two-part domain name; and sometimes even three- or four-part domain names.
In general, American addresses end in an organizational suffix, such as ".edu," which means the site is at a college or university. Other American suffixes include:
.com
.org
.gov
.mil
.net
Sites in the rest of the world tend to use a two-letter code that represents their country. Most make sense, such as `.ca' for Canadian sites, but there are a couple of seemingly odd ones, at least if you don't know the ISO 3166 standard international abbreviations. E.g., swiss sites end in `.ch' (Confederatio Helvetica), German sites end in `.de' (DEutschland), while South African ones end in `.za' (from the archaic spelling Zuid Afrika). Some U.S. sites have followed this international convention (such as well.sf.ca.us).
You'll notice that the above addresses are all in lowercase. Unlike almost everything else having anything at all to do with Unix, most Net mailing systems don't care about case, so you generally don't have to worry about capitalizing e-mail addresses. Alas, there are a few exceptions -- some public-access sites do allow for capital letters in user names. When in doubt, ask the person you want to write to, or let her send you a message first (recall how a person's e-mail address is usually found on the top of her message). The domain name, the part of the address after the @ sign, never has to be capitalized.
It's all a fairly simple system that works very well, except,
again, it's vital to get the address exactly right -- just as you have
to dial a phone number exactly right. Send a message to tomg@unm.edu
(which is the University of New Mexico) when you meant to send it to
tomg@umn.edu (the University of Minnesota), and your letter will either
bounce back to you undelivered, or go to the wrong person.
If your message is bounced back to you as undeliverable, you'll get an ominous looking-message from MAILER-DAEMON (actually a rather benign Unix program that exists to handle mail), with an evil-looking header followed by the text of your message. Sometimes, you can tell what went wrong by looking at the first few lines of the bounced message. Besides an incorrect address, it's possible your host system does not have the other site in the "map" it maintains of other host systems. Or you could be trying to send mail to another network, such as Bitnet or CompuServe, that has special addressing requirements.
Sometimes, figuring all this out can prove highly frustrating. But remember the prime Net commandment: Ask. Send a message to your system administrator. He or she might be able to help decipher the problem.
[section on UUCP addresses deleted]
If you want to get a taste of what's possible through e-mail, start an e-mail message to
almanac@oes.orst.edu
Leave the "Subject:" line blank. As a message, write this:
send quote
Or, if you're feeling a little down, write this instead:
send moral-support
In either case, you will get back a message within a few seconds to a few hours (depending on the state of your host system's Internet connection). If you simply asked for a quote, you'll get back a fortune-cookie-like saying. If you asked for moral support, you'll also get back a fortune-cookie-like saying, only supposedly more uplifting.
This particular "mail server" is run by Oregon State University. Its main purpose is actually to provide a way to distribute agricultural information via e-mail. If you'd like to find out how to use the server's full range of services, send a message to its address with this line in it:
send help
You'll quickly get back a lengthy document detailing just what's available and how to get it.
Feeling opinionated? Want to give the President of the United States a piece of your mind? Send a message to <president@whitehouse.gov>. Or if the vice president will do, write <vice-president@whitehouse.gov>.
Last update 26 February 1996
http://www.ccrc.wustl.edu/spj/surf/email.html
Prepared by Lorrie Faith Cranor (lorracks@cs.wustl.edu) and Staci D. Kramer (sdk@cris.com)