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Okay, now that we've looked at the three basic sizes in which information typically travels across the Internet, let's look at the seven most common uses of the Internet, and some of the details of each.
Electronic mail, or email, allows users to compose a memo and send it to a group or individual anywhere on the Internet, and also to read messages sent to them. Email messages are similar to paper letters, except that they are cheaper to send, easier to duplicate, and travel much faster.
Basic email is for person-to-person communication, as is a letter. However, email can be used to reach wider audiences using emailing lists or a listserv. Emailing lists keep interested persons updated on a specific topic, just as mailing lists for postal mail do. For example, the Association for Computing Machines (ACM), an undergraduate organization for computer science students keeps an emailing list which keeps its members informed of upcoming events.
The listserv is a mailing list with a twist; not only do subscribers receive all messages, but any messages sent to the listserv's address are forwarded to everyone else. That is, the communication is more than one-way. Listservs are useful for holding a discussion about a topic of limited interest among several people. The policy of sending each message to all participants simplifies the distributions to a large number of people, and keeps everyone abreast of all points of the conversation.
Once you're connected to the network, using email is only slightly more
complicated than typing up a memo using your favorite word processing program.
The only additional factor is specifying a recipient. The rules for the
Internet specify phrasing email addresses like so:
username@machine.network.type
For example, one of my old email addresses is graham@cs.utexas.edu
graham - that's my name. Not only that, it's how the machine where my mail was sent knew me. When I ask the machine if I've received any mail, it asks me who I am. I tell it I'm 'graham', and provide a password to prove it.
cs.utexas.edu - that's the name of a computer. In fact, it's the name of the computer where my mail was being sent.
The 'cs' stands for the Computer Science department; since I was a computer science major, I had an account on their machines and it's where I got my mail.
'utexas' stands for the University of Texas, where I went to school. Others are 'tamu', 'sfasu', and 'mit'. For major universities, these are usually not too cryptic. Since there are so many businesses, corporate email accounts can be a bit more confusing, but generally this part describes who provides the email service.
The last part is 'edu', which means that the computer belongs to an educational site. Other possible endings are
Sites in other countries also usually have a fourth identifier for their country:
Those of you familiar with Compuserve or one of the other online services may do email differently. On Compuserve, rather than a username, you are given a unique number to identify you, such as 71173,2123. Not to worry, however; people who are not on Compuserve can still send you email using the regular Internet. Simply replace the comma in your number with a period, and append "@compuserve.com" (since Compuserve is a commercial site). Thus my old BSU director's email address on Compuserve is 71173.2123@compuserve.com.
Note: You wouldn't have had to know any of this stuff to send me a message. All you'd have had to do is put "To: graham@cs.utexas.edu" at the top of the message, and your computer would take care of the rest. But knowing the details makes it a little less cryptic.
Newsgroups have been around just as long as electronic mail, and are one of the oldest uses of the Internet. (In fact, they are one of the reasons that computers were originally networked.)
Think of a newsgroup as an electronic bulletin board. Using your computer, you "approach" a certain newsgroup, say rec.pets.cats (recreational group about pets, specifically cats). You browse through a list of subject lines for hundreds of messages on the group. You can then read the full text of any message which looks interesting. The format is much like an email message, but rather than being sent to a particular person, it is just sort of tacked up on a virtual wall for anyone to read. You can also tack up messages yourself, or reply to a message that has already been posted. Thus anyone reading the original message will also see your reply.
Newsgroup postings are arranged into groups by topic, and the name of each group generally gives you the theme of all postings in that group. Some sample groups are:
and so on.
Originally, there were seven main "hierarchies" which divided newsgroups according to their nature:
Shortly thereafter, an eighth heading, 'alt' (alternate/alternative) was created to keep some of the noise out of some of the computer-related groups. Now hundreds of hierarchies exist, many of them regional (such as austin.forsale, which is in the regional Austin hierarchy). From about a hundred news groups in the mid-eighties, they have exploded to over ten thousand, on topics from Bosnia to Calvin and Hobbes.
For considerably more information on the nature and history of newsgroups, see the report on my own web page at: http://www.onr.com/user/mitchell/usenet/
Of all the forms of on-line communication, chatting on the Internet most resembles talking on the phone or attending a high-school reunion. In each of its forms, chat consists of one or more people communicating in real-time. Once a single comment is submitted, it is immediately transmitted to everyone involved in the conversation.
The most intimate form is talk, a program available primarily on Internet-connected UNIX systems (although programs exist which allow you to use talk on your Windows or Mac machine). Talk allows two users only to communicate, and each participant is presented with a split screen, typing in the upper half and receiving in the lower half. Each character is transmitted as it is typed, allowing one to see not only the message, but how many times the word "receive" was typed and retyped before a spelling was settled on. Both participants can send and receive simultaneously, so even interruptions are conveyed.
A slightly broader form of chatting is found in lots of places, including IRC (Internet Relay Chat), many bulletin-board services (BBSs), and recently even in school classrooms. Known as 'chat' or 'interchange', this form features a split screen which is presented to each of many participants. Comments are composed in the lower segment, while the comments of others are listed above, each attributed to the appropriate "speaker". Each statement is usually sent in one big chunk when the composer is ready. This way complete thoughts are grouped together, and if one person needs to drop out to go fetch a dictionary, there is no lag in the "conversation".
Usually, chat sessions are organized by topic. For example, in IRC, users choose which forum to join. Thousands of forums exist, on topics from cats to sex. If a forum contains only two participants, then IRC resembles talk.
Lots of newer software is now becoming available which allows to users to really talk over the Internet, not by typing, but by speaking into a microphone. This has the advantage over the telephone in that it is free (except for the cost of your Internet service). One popular program is the Internet Phone or IPhone, found at http://www.vocaltec.com/home.html.
File transfer allows you to give an arbitrarily long file to another user, or to receive such a file. Examples include: reports written in WordPerfect 5.1, spreadsheets, digital pictures, programs like the computer game DOOM, or entire databases. Files may be sent to (uploaded) or retrieved (downloaded) from machines and not just users, allowing you to download a picture from a web page without direct human intervention.
FTP, the File Transfer Protocol, is both a set of rules that computers use to send files to each other and the name of a program/application which implements those rules. Versions of FTP can be found for virtually any machine out there, and using FTP, you can download information, lists of frequently asked questions and their answers (FAQs) on a variety of topics, or get the latest greatest version of a shareware movie viewer for your home PC.
The World-Wide Web is the most used but least intimate of the methods of Internet communication, and is almost solely one-way, (although it is common to send email messages from a web page, allowing limited responses). A finished document is put up on a publicly-accessible site, and other users visit it at their leisure. More like publishing than anything else, the user sees the Web page like a magazine, with little ability to alter its content.
Certain sections of the page are 'hyperlinked' to other pages. The genius of the Web, however, is that links are not only to pages by the same author, but could be to other pages, which the author had nothing to do with. Thus the user can travel seamlessly from one page to a related one, even if the pages are stored thousands of miles apart. In this way, the Web is like an encyclopedia which says "see ALEXANDER HAMILTON" at the end of an article. And jumping to the other page doesn't require a second search; it is immediately accessible.
Unlike standard email or newsgroups, which are limited to text, Web pages can show color, pictures, sound, music, or even animations. Thus the Web is a bit more appealing than standard media, and helps explain its increasing popularity (the number of 'pages' you can visit is currently over 30 million, with over a million added each month).
Rather than communication, the Web is more suited for dissemination, and it does so well. The Web is a good place to get lost and find information on things you never knew existed, or to make your own information easily accessible.
You may have wondered about Web addresses. Just what does http://www.nuqneH.org/aftershock/index.html stand for anyway?
http stands for Hyper-Text Transfer Protocol. It refers to the set of rules for sending a hypertext document (like a Web page) across the Internet. It is similar to, but not the same as the File Transfer Protocol previously discussed.
The "colon-slash-slash" is just a part of the phrasing, like the '@' in an email address.
www.nuqneH.org is again the name of a computer (just like cs.utexas.edu). www is the computer on the network nuqneH.org which handles incoming requests for Web pages. It knows the hyper-text transfer protocol, and uses it to send out Web pages.
nuqneH.org is the name of a network or site; notice it is an 'organization'. nuqneH is the name they chose for themselves when they were registering the site with the Internet; it is a Klingon word (from Star Trek) meaning hello (literally "what do you want"). (By the way, I looked that up on the Web.)
/aftershock refers to the directory named "aftershock" on the previously named computer, in this case www.nuqneH.org. And index.html is a file in that directory. The html extension stands for Hyper-Text Mark-up Language and is the way Web pages are defined/coded. If you don't specify a specific page (with an HTML extension), but just a directory, the remote computer will assume you want the one called index.html.
So, http://www.onr.com/user/mitchell/wide.html is a request for the computer www.onr.com to send you the file wide.html, using the hypertext transfer protocol. The file should be found in the directory /user/mitchell. That's it. And http://www.ibm.com just refers to the file index.html on the computer www.ibm.com, in the root directory ("/").
Remote login allows a person sitting in front of one computer to connect to another computer (in a different place) and use it as if it were physically present. It appears that a window on the user's machine connects directly to the remote machine because each character that the user types is sent to the other machine, and each character that the remote computer displays is sent to the user's machine and displayed in the window.
Telnet is the name of the most popular program that allows you to remotely login on another machine. 99% of the computers in the world which you can log in to remotely are running some version of UNIX, since UNIX is designed for many users to share the same machine, and since many versions of UNIX are free. UNIX is an operating system, and it runs the remote computer the same way DOS or Windows runs a PC or System 7 runs a Mac.
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Introduction · Uses of the Internet · Getting On the Net · What To Do With It · Recommended Reading