April 12, 2011, 2:51 p.m.
posted by juff
E-mail, like regular mail (usually referred to by e-mail advocates as snail mail) needs an address, usually called an e-mail address. To send mail to a person, you send it to his or her username (refer to Chapter 1 for information about logging in with a username). If the other user uses a different computer than the one you use, the mail system has to know which computer the other person is on — and the address becomes more complicated.
For people who use the same mail server you do (roughly, you both use PCs connected to the same mail-handling computer running UNIX), the mail address is just their username. If you enter georgew for your username, that’s your mail address, too. Make sure that you don’t use uppercase letters in the mail address unless the username also does.
You can send mail to people who use other mail servers if they’re connected by a network. For people who use other computers, you send mail by telling the mail system which mail server they use.
Servers have names too, you know. They sometimes have boring names that indicate what they are used for, such as marketing or corpacctg. When you’re writing to someone elsewhere on your network, include the server name in the mail address by using an at sign (@) to indicate where they are "at." If your friend Nancy, for example, has the username nancyb and uses a server named ginger, her mail address is [email protected].
A skillful system administrator can automatically note which computer each user in an organization uses. With luck, you can merely send mail by username, and the system automagically figures out which computer to send it to.
Tip If you have trouble with addresses, the easiest way to send a message to someone is to wait until that someone sends a message to you and then reply to it. All mail programs have a command (usually r) that replies to the message you just read. Messages almost always have return addresses, and the r command enables you to send a message without typing an address.
If your computer network has phone connections to the outside world, you can probably also send mail to people out in the wide world of the Internet. Check with your system administrator or other e-mail users to find out whether your organization is “on the Net” (connected to the outside world).
To correspond with people on the outside, you need an Internet address for the person you want to send mail to. After you have the address, type it exactly the way she wrote it. Internet addresses tend to look like this:
The part in front of the @ is the person’s username. The rest of the address is the name of the mail server and other information about where it is, usually the name of the company. The computer name, company name, and so on are connected by periods. The last three letters frequently tell you what kind of organization it is: com is for companies, for example, and edu is for educational institutions. Sometimes the parts of the address spell out the city, state, and country where the computer is located. It’s all very well organized, really.
If your computer is on the Internet, you can also exchange mail with users of commercial services, such as CompuServe and America Online (AOL). For details, see the following sidebar, “Sending mail to people who use online services.”
Tip When you are typing Internet addresses, keep these points in mind:
Be sure you don’t type any spaces in the middle of the address. Don’t use spaces in usernames or computer names or on either side of the @ or a period.
Don’t capitalize anything unnecessarily. Check the capitalization of the person’s username and computer name. Most addresses are composed entirely of small letters.
If your computer is on the Internet and you want to try out network mail, send a message to the authors of this book, at [email protected], and tell us what you think of the book. Our computer sends you an automatic reply, and we read your message, too. (If you can get that address right, you’re already halfway to being a mail wizard.)
If you get an address wrong, you usually get the message back within a few minutes (for mail on your own computer or your own network) or a few days (for mail that has bounced around the Internet). The dead letter usually has all kinds of cryptic automated error messages in it, but the gist is clear: The message wasn’t delivered. Check the address and try again. Generally, the safest way to address a message is to reply to someone else’s message.