EMAIL 101 by John Goodwin, this is an Alpha test version, your
suggestions will be included in the Beta test versions, and in the final editions.
This rough version is missing 8 out of 28 chapters and 1 out of 5 appendices.
Copyright (c) 1993 by John E. Goodwin. All Rights Reserved.
You may make and distribute verbatim copies of these course notes for non-commercial purposes using any means, provided this copyright notice is preserved on all copies.
For information on taking the internetworking course, contact
John Goodwin (jgoodwin@adcalc.fnal.gov)
P.O. Box 6022
St. Charles, IL 60174, U.S.A.
1
<title> E-MAIL 101
If you like those little machines that give you 24 hour access to your bank account, you'll love the Internet. I suppose there are still people who, given a choice, will go to a drive-through teller just so they can deal with a "live person" instead of a machine. But even those people will admit that it is nice to have the option of doing things for yourself, on your own schedule, anywhere. Do you remember what it was like before automatic tellers? Banks closed at 3 p.m. on weekdays. Each Saturday you had to guess how much money you would need for the following week. If you were wrong you had to cash a check at a food store (and maybe buy something you didn't want). And if you were out of town? Well, there were always credit cards.
We don't do that anymore. I think many people go to the automatic teller because they like the privacy of handling their own business without having to explain it all to someone else. And we like the illusion of having access to our "own" account anytime we want. There are disadvantages to using an automatic teller card too—you may have to pay a fee each month or even for each transaction—and you have to remember to deduct those fees from your account balance or you will bounce checks. But I'll bet you feel pretty competent using an automatic teller and don't lose much sleep worrying over the fees.
This course is designed to give you that same sense of freedom and competence with the Internet that you have with an automatic teller machine or the telephone. With a home computer, a modem, and communications software, you can connect to other computers over the phone line to exchange electronic mail (E-mail), trade files, or search for information. Many of those computers are connected to the worldwide network called the Internet. Some few of them will—for a fee—let *you* connect to the Internet. From there you can dial any of 900,000 or more computers, send E-mail to any of 25 million people, and access hundreds of free, informative services.
In short, you are on the verge of a new method of communicating with people and machines called "internetworking." Internetworking lets you:
o Avoid playing phone tag;
o Sign up to receive special interest electronic newsletters and journals;
o Access hundreds of information services and document collections in exactly the same way—no need to have hundreds of sets of different instructions or hundreds of (expensive) special purpose software packages;
o Find and communicate with other people who share your interests.
Internetworking is an essential skill for the '90s. Your children will find it as common as viewing television or using the telephone. It still has a few rough edges—but we'll explain those.
There is actually no single network owned by one company called the Internet. Instead, many medium-sized networks have grown together to create a "phone system" that connects together nearly a million computers. Many hundreds of these computers allow some form of public access. You can get the latest news or weather, download information about Government programs or high-tech products, search on-line library catalogues and databases, download free software, and do many other things, with little or no monetary investment beyond the cost of your home computer.
Using the Internet need not be expensive: you can get on the Internet for as little as $10 a month if you own (1) a home computer, (2) a $50 modem, and (3) some communications software (under $100). There are more expensive ways to connect to the Internet, of course. These ways make sense for businesses or organizations that make heavy use of the network. But in this course we will discuss methods that cost in the $10-$40/month range. These methods are suitable for exploring the net after hours and for casual use. We will provide some basic information about more expensive methods of connecting (Appendix C) so that you can make informed decisions if your networking needs should increase in the future.
Internetworking well means mastering a whole host of skills—connecting two computers together using the Internet is just the beginning. You have to learn methods for transferring information from the remote computer to your own. This is a complex task that may involve using a file transfer protocol and compression techniques.
Because the information world is so vast, your biggest problem will most likely not be connecting to the Internet. It will be finding what you want. Thus, this course covers not only the mechanics of making a connection and transferring files, but techniques for locating material as well. And of course you will want to be savvy about the costs of different connection methods. This means estimating whether it will cost you more per Megabyte to transfer the information or to have it faxed to you by a friendly librarian.
This course is intended for the general public—students, businesspersons, librarians, teachers, writers, journalists—in fact anyone who needs to find information and communicate with others. Whether you are researching a paper, writing an article, or trying to get technical information on a product, you will use these techniques over and over.
Chapters marked with an asterisk are omitted from this edition.
COURSE CONTENTS
1 : The Past and the Future of Internetworking
2 : What Is the Internet?
3 : How Do I Connect to the Internet?
4 : Who Pays for the Internet?
5 : Internet Basics
6 : Getting on the Internet Step by Step
7 : Programs and Pictures
8 : File Compression Methods for Faster Transfer
9 : What to Do When You Only Have E-mail
10 : Employee Development: How to Get Your Employees Internetworking
Part II Special Concerns
11 : Special for Businesses
12 : Special for Students and their Parents
13 : Special for Writers, Journalists, Publishers, and Printers
14 : Special for Elementary and High School Teachers
15 : Special for Librarians
16 : Special for Scholars
17 : Special for Churches, Synagogues, and Mosques
Part III Research, Organization, and Writing
18 : Research Methods I: Basic Navigation Methods
*19 : Research Methods II: Usenet Newsgroups
20 : Research Methods III: Advanced Techniques
*21 : Organizing Information
*22 : Information Structures
*23 : Boolean Logic
*24 : Writing for an Internetworked World: Basic Problems
*25 : Writing for an Internetworked World: Getting Through to your Audience
Part IV Resources
*26 : The Internet Address Book
27 : Bibliography
*28 : Glossary
Appendix A. Computer Hints for the *Really* Green
Appendix B. Using a Modem
*Appendix C. Technical Details of an Internet Connection
Appendix D. Just Enough UNIX
Appendix E. The Ten Best Things To Get If You Only Have E-Mail
<Chapter 1> The Past and Future of Internetworking
There is an old fashioned way to connect with other computers and share information and there is a modern way. It is helpful to compare the two methods briefly in order to make contact with methods you may already know and to show off the advantages of using the Internet.
The old fashioned (ca. 1980) method of making contact with other computers is through a bulletin board service (BBS). Bulletin board services grew up in the late 70s as a method for sharing software, talking, playing games, etc. with a personal computer. They range in size from small special interest Bulletin Boards with a local following to giant national boards like CompuServe, GEnie, and The Source. You access a bulletin board with a modem and communication software by dialing a telephone number. Of course, if you don't live in the local area of the BBS you have to use a long distance carrier. This may add a couple dollars per hour to the connect fee.
The basic services offered by a Bulletin Board and by the Internet are similar:
(1) Access to a host computer (Internet TELNET command)
(2) File transfer capability (Internet FTP command)
(3) The ability to contact other BBS members individually (Internet
E-mail)
(4) The ability to post messages for general consumption in any of
several catagories. (Usenet Newsgroups)
The difference is that whereas each BBS has its own dialup procedure, menu interface, file transfer methods, billing policies, and so on, THE INTERNET USES ONE METHOD FOR ALL COMPUTERS IN THE WORLD. The savings in terms of the "learning curve" is staggering. Once you know how to use anonymous FTP you know how to get information from *hundreds* of providers. It is like the difference between using the postal service or using a special courier for each person you write a letter to. Once you know how to address the envelope and put the stamp on, you can write anyone.
The Internet has the added savings that any communications software you buy for it works with all providers. You do not have to buy (or customize) special software for each information provider. Thus you can use one familiar graphical user interface ("windows" program) to connect with any computer. The usual situation where you have to buy a special "client" program to connect to each kind of "server" is replaced with a situation in which you have a single program that any "server" out there has to comply with. This standardization is the main advantage of using the Internet.
Bulletin Boards are still around. In fact, one of the easiest ways to connect to the Internet is through a national bulletin board service. One disadvantage of this method is that—as of this writing—national BBS's like CompuServe offer only E-mail. You can't FTP or Telnet from them. And they often charge per message for E-mail, so using them can be quite expensive. There are better ways.
<Chapter 2> What is the Internet?
The best way to think of the Internet is as a communications medium like the Telephone, Television, or the Postal Service. Using the Internet you can send a any written text by E-mail. This is rather like mailing a letter and having it arrive in seconds—three days in the most backwards parts of the world. Using a special protocol called File Transfer Protocol you can transfer text files that are too long to mail (over about 50 pages) or even transfer graphics and programs. If E-mail is the equivalent of "talking" to a person, then Telnet, the third main Internet service, is equivalent to telephoning a computer. As long as you know the password for logging on to a computer, you can access and search any of nearly a million computers. Details of E-mail, FTP, and Telnet are contained in Chapter 5, Internet Basics.
This chapter puts the Internet into context. Rather than concentrating on the trees that will occupy us in later chapters, it paints a big picture of the computing world in which the Internet has evolved. When you pick up a telephone receiver you know you can dial households, businesses, or government offices. You can dial 800 numbers or 411 for information. You know how to get the time or weather, get your credit card balance, or leave a message on an answering machine. In short, you have a good idea of what might possibly be at the other end of the line and a great deal of experience with negotiating their various intricacies. But you are new to the Internet. Some sense of "what's out there" in this new world is necessary to avoid getting lost in the thickets of acronyms, numbers, and procedures developed by different vendors.
As we approach the middle of the 90s, the normal working situation in offices is approaching something like this: there is a Local Area Network (LAN) connecting together personal computers, workstations, and mainframes of different makes. The LAN (pronounced like "land" without the "d") may be connected to other LANs as part of a Wide Area Network (WAN). The WAN may or may not be part of the global network called the Internet. In colleges, universities, and research laboratories it likely is part of the Internet; in the commercial world, except for a few high-tech companies, it likely is not. But the difference between academia and the commerical world is rapidly becoming blurred.
In addition to the LANs and WANs there are many, many home and office computers that *could* be part of the global network using a modem-to- host connection. These computers can be the portable computers of outside salespersons connecting to the central office to file a report, a computer in a home-operated desktop publishing company connecting briefly to the Internet to get a graphic for a newsletter, or a parent sending E-mail to their child at college.
<Section 2.1> Getting Over Shell-Shock
Let's face it. Not many members of the public—even the computer literate public-are on the Internet. There are three reasons that using the Internet for the first time can be rather intimidating, even though it is actually rather simple to use, when you get down to the nitty- gritty of internetworking:
o Getting on to the Internet can be a little bit complicated;
o The capability of logging on to computers you've never used before by its very nature means facing unfamiliar—and hence uncomfortable— situations; and
o The world is a very big place.
I like to think of the first problem—getting on to the Internet—by remembering what it was like using an "alternative" long distance service before the breakup of the Bell monopoly. People who used the alternative carriers had to dial all sorts of access codes—very often a local access number, a credit card number, a security code, *and* the number of the party they were calling. They knew that whatever came after that was going to be easier.
That's what getting on the Internet is like. You may have to dial a local access number, get your modem settings right, and type the right magic combination of words; but after all that, actually *using* the Internet is simple. We'll talk you through the initial steps—after a while (and some frustration) it will be as unconscious as unlocking your front door or tuning a television set.
The second problem is a little more substantial. Using the Internet, you can get yourself into situations that are, well, experimental. Because the Internet gives you the freedom to "go anywhere" and "do anything"—at least if you know the passwords—you can uncover strange incompatibilities and unfamiliar systems. I call this experience "shell shock". At some point you will likely find yourself face to face with a computer program that expects you to type a command you don't happen to know.
You can mostly avoid such situations by only trying things about which you have good information. The situation is not much different from using a telephone: if you stick to well-worn paths like dialing local numbers or simple long distance calls, you will have little trouble; but if you start dialing other countries or special numbers you may be in for a surprise or two.
When you do log on to a new (previously unknown) computer, you can expect to come face to face with something called a "shell prompt". Shell prompts look like this:
% (or some other obscure symbol, like a dollar-sign)
or this:
mail> (a favourite—means you're in some sort of mail program)
or like this:
prez23:
(means 23rd command since you logged into computer "prez").
A prompt means the other computer expects you to type a command for its "shell", or "command interpreter". The shell is the outer layer that you, the user, interact with.
Two other types of "user interfaces" you might encounter are:
o menu systems that give you choice of numbers
o "window" systems or graphical user interfaces (GUIs, pronounced "gooey").
Menu systems are popular on bulletin board services, and usually present no problem to the novice. Their weakness is that they get cloying after about five minutes. Most menu systems that are designed to be used for that length of time or longer have a "command mode", where you get—you guessed it—a shell prompt.
Even windowing systems (you know if you have one of these) very often give you a window that "emulates a terminal", i.e. that gives you a shell prompt inside.
So, you see, in each of the three common user interfaces—command line, menu-driven, or graphical user interface—you will likely encounter, at some time in your life, a shell prompt. Advice on things that will likely work to get you started is given here and in Appendix A. Some experience of other kinds of computers, especially computers that use the UNIX operating system is useful. Some tips about using UNIX and other operating systems you may not have encountered before is given in Appendix D.
If you do get stuck, whether by being experimental or just by accident, it is helpful to remember a few points:
o You can always disconnect from a remote service by using your communications software to "hang up".
o If the computer gives you a strange symbol like a percent sign or a dollar sign and just sits and stares at you, you can try "help" or "?" to try to find out what the computer expects, or else try "exit", "quit", "bye", "logoff", or something similar, to return to where you were before.
o Many times, when you log on to a system, you will get instructions on how to get further help or how to "escape" back to your own system. You should remember these or write them down!
o As a last resort, exit the communications program (and all other active programs) and shut off your computer, turn off your modem, and disconnect it from the phone line. Be sure to do these steps in the order prescribed. It is unwise (though tempting) to simply turn your computer off and on, or to pull the plug on your modem with your computer running.
More suggestions for the inexperienced are given in Appendix A.
The final hurdle to using the Internet is that the world, even the world of the Internet, is indeed a very large place. When using the Internet you have to decide:
o where to go;
o what information you want (and where it might be); and
o how to get to it (and get it back home intact).
For a system as vast as the Internet, these are hard decisions. Often, the only strategy that works is to explore and try different things. This course is designed to get you over the initial hurdles, give you a fair grounding in methods that work, and point you in the right direction. The exploration is up to you. As an initial orientation, we describe the "three worlds of the known Internet" in the next section.
<Section 2.2> The Three Worlds of the Known Internet
The Internet, like ancient Gaul, is divided into three parts. These parts are not so much territories as worlds, each with their own sets of assumptions, favorite dialects, and favored equipment. We may conveniently refer to them as the "PC world", the "UNIX world", and the "Mainframe world". Here's a dossier on each of the three worlds:
World: Personal Computer (PC)
Typical Equipment: IBM PC and clones (85%) , Macintosh (15%)
Conventional Operating Systems: MS-DOS, OS/2
Windowing Systems: Windows, MacOS
Typical Size: PC ($1k to $5k typical; few $100 used)
Clientele: Mixed—Business, Home users, just about everybody
World: (mostly UNIX) workstation
Typical Equipment: Sun Workstation, VAXStations, other vendors
Conventional Operating Systems: UNIX (two major dialects), VMS
Windowing System: X Windows
Typical Size: Workstation ($5k and up)
Clientele: Engineering/Scientific users; more and more businesses
World: Mainframe or Minicomputer
Typical Equipment: IBM (various), Digital Equipment VAXes
Conventional Operating Systems: VM, VMS, UNIX
Windowing Systems: X Windows, if available
Typical Size: Minicomputer or Mainframe ($10k to millions)
Clientele: Big Business, Universities, Government
The neat picture of three worlds is distorted somewhat by a tendency for each of the worlds to have two (or a few) major options, either in choice of equipment, operating system, or vendor. So, for example, the PC world is split into two camps, the MS-DOS people and the Mac people. Similarly, the UNIX world is split into the "BSD" workstations and "System V" (i.e. "5") workstations.
The three worlds are reflected somewhat in networking. The Internet is dominated by minicomputers and workstations running UNIX and VMS, with an ever increasing influx of PCs running MS-DOS and Macs. Machines running other operating systems often put a "UNIX-like" foot forward, so the user can almost believe he or she is dealing with UNIX machines. There is a certain sense that the UNIX software is the standard for the Internet. Software tends to appear on UNIX machines first and then be "ported" to other machines.
What makes it possible for all these disparate machines to talk to each other is the "Internet Protocol" (known more formally as TCP/IP, for Transport Control Protocol/Internet Protocol). TCP/IP can be thought of as a set of rules for two computers to use when they communicate with each other, even if they are not from the same vendor.
We are used to thinking of computer systems as having "software" and "hardware", but it is closer to the truth to say that complicated systems like the Internet have many levels—in the case of the Internet as many as seven—ranging from "very software" to "very hardware". Each level has its own set of rules, called its protocol. The TCP/IP protocol belongs to two of the middle levels. At the moment, the most common protocol for the two most "very hardware" levels is "Ethernet" (looks rather like the coaxial cable used for cable TV), while the "very software" levels are completely dependent on the vendor. In fact, it is this profusion of levels which lets the Internet work on just about any kind of hardware and with software from many different vendors.
Anyway, the Internet grew up as several medium-sized networks, all having diffent "very hardware" and "very software", but using the TCP/IP protocol for their middle layers, were connected together. Two of the first, and biggest, nets to adopt the Internet Protocol were ARPAnet— Internet was first designed for this one—the network for what used to be called DARPA (the Defense Advanced Research Projects Agency of the U.S. Department of Defense), and NSFnet, a network connecting universities and government laboratories for the U.S. National Science Foundation. These and other large networks form the "backbone" of the Internet. But today there are hundreds of smaller nets hooked on to the backbones.
There *are* big networks that don't use TCP/IP. For example, in the context of IBM mainframes at large universities and research institutions, BITnet (The "Because It's Time" Network) emerged. This large worldwide network does not use the Internet protocol. BITnet can be reached from the Internet through special translators called gateways, but it is definitely a different network. Occasionally one encounters problems that can be traced to this fact.
<Section 2.3> The Future of the Internet
The future of any technology is difficult to forcast, and I do not profess to know what the future holds for the Internet. Some predictions that various forcasters have made for internetworking (and telecommunications in general) are:
o A proposal for a data "superhighway" called the NREN (National Research and Education Network) will pass the U.S. Congress. This is an upgrade for the Internet.
o Commercial use of the Internet will become more common and new schemes for charging for its use will emerge.
o The Internet will be handed by the government over to AT&T and the other "telecoms", who will charge so much to access it that the whole scheme will collapse.
o Optical Fiber will replace Coaxial Cable (Ethernet protocol) as the most common standard for LANs.
o The Internet will enter the home over ordinary phone lines.
o The Internet will enter the home over existing Cable TV coaxial cable.
o The Internet will enter the home through newly strung optical fiber as part of a unified system for Telephony, Cable TV, and the data communication, using [insert your favorite protocol here] as a standard.
o Personal Computers will replace telephones, answering machines, stereos, CD players, and VCRs—maybe even TV!—as a single, universal device for home use. Sounds like a good thing to connect to the NREN.