Read this chapter to satisfy your curiosity about how people locate, retrieve, and use information that's available on the Internet. The answers include these:
They use other people's computers as their own.
They locate and copy files.
They burrow with Gopher.
They search with Veronica.
They browse the World Wide Web.
I should point out from the beginning that any of the communications techniques described in Chapter 6 can also serve as research tools. People learn a lot from mailing lists and newsgroupsand when they don't see the answers, they can post their
own questions and receive a dozen or more answers within hours.
When a user can scare up the Internet address of an expert (something that's getting easier as more folks list their Internet addresses in books and at the ends of articles in magazines and journals), he or she can e-mail a polite question. If the
expert is not an especially busy expert, he or she may respond. Those lucky enough to establish an e-mail rapport with knowledgeable people may even dare to take the relationship a step further, initiating a Talk session to make those discoveries that come
only through conversation.
So although the techniques in this chapter overlap those in Chapter 6, here you'll mostly see how users extract information straight from the other computers on the Internet, usually without having to enlist the assistance of another person.
Newsgroups and mailing lists (described in Chapter 6) are two Internet resources that make finding and supplying information easy because they all work basically the same way; that is, if a user knows how to find information and post information in
one newsgroup, he or she knows how to use them all. Ditto mailing lists, for the most part. Newsgroups achieve this consistency because they all conform to the Usenet format. Mailing lists are consistent because they all rely on the same e-mail-based
approach.
Unfortunately, many other Internet resources are not consistent in the way they look and in how they're used. Out on the Internet are thousands of computer systems that are managed not for the benefit of the whole Internet community but for the use of
a smaller groupa university faculty, a research staff, a federal agency. Each system has its own way of doing things: a different way of organizing information on the screen, a different set of commands, a different set of rules for who can do what.
These systems are set up in whatever way best suits their primary users, and Internet visitors are expected to learn, when in Rome, to speak the local language.
To access most of these computer systems, Internet folk use a facility called Telnet. Telnet enables an Internet user to drop in on another computer system and use it as if he or she were one of the computer's primary users. (The procedure is
sometimes also described as remote login.) Within some limitations that you'll learn about later, Internet users can look through a college's library catalog as if they were students at that college. Likewise, they can consult the resources of a think tank
as if they were one of the researchers, and poke around in the computer systems of government agencies, public libraries, and businesses.
Did You Know...
The word Telnet is also used as a verb to describe the action of using Telnet to access another computer, as in "I just telnetted to the FDA Library to learn about recent drug approvals."
You may also hear references to "Telnet sites." These are simply the places where the computers that run Telnet-accessible resources are located.
But here's the catch: When an Internet user telnets into Harvard's campus information system, that user sees on his or her screen exactly what students and faculty at Harvard see the same lists of options, the same information. If a user telnets
to Dartmouth's system, that user sees what the students and faculty at Dartmouth see. The problem is that the systems of the two universities aren't used in exactly the same way (see Figure 7.1). Before the Internet user can use any given resource through
Telnet productively, he or she may have to feel around a little to figure out how things are done there.
Learning to use e-mail, newsgroups, and mailing lists is a snap, as you may have discovered while reading earlier chapters. More than anything else, it is the inconsistency among the many Telnet systems that leads people to see the Internet as a
complicated system usable only by computer virtuosos.
Fortunately, any computer user with a little experience can quickly come up to speed of most Telnet systems. As Figure 7.1 suggests, nearly all Telnet systems can be operated through menus.
Figure 7.1a. and 7.1b Two different university information systems on the Internet, reached through Telnet.
Curious About the Word?
A menu is a list of choices displayed on the screen. Menus are particularly important in using Telnet systems and in using Gopher and World Wide Web resources, both described later in this chapter.
To use a menu-based (often called menu-driven) Telnet system, users read each list of choices presented on the screen and pick what they want. Each menu item has a number next to it (see Figure 7.1); picking an item typically requires nothing more
than typing the number of the desired menu item, then pressing the Enter or Return key. On a small but growing number of systems, the user may use a computer mouse to move an on-screen pointer to an item and click the mouse button to select it.
Typically, a user moves through several menus to get something done. The user will pick one choice from a broad main menu (also called the opening menu or top menu, it's the menu that appears as soon as the user arrives at the system). This will bring
up a more specific menu of choices related to the chosen item. The next selection may bring up an even more specific list. Eventually, after passing through several menus, the user arrives at the information he or she seeks.
Often the wording of menu choices can be a little cryptic, so users sometimes take the wrong route and hit a dead end. It's usually easy, however, to "back out" through the menus to the starting point, from which the user can start over by
trying a different menu item. A little trial and error almost always gets users where they want to go.
Telnet resources vary not just in their menuing systems, but in other ways. In particular, they may require a procedure called "logging on" or "signing on"supplying a username and password in order to use the system. The
username/pass-word routine exists to enable the computer to keep track of its users and to control access to sensitive information or features.
For example, a professor at a university may be allowed to look at grade reports, but students may not be. In a business, the chief accountant and other executive officers are typically allowed to see financial data that most employees are forbidden to
see. Because each user of a computer system signs on with a unique username, the computer knows who's who and can restrict a user from seeing what that person is not supposed to see. The secret passwords ensure that people can't use the system dishonestly
by signing on with someone else's username.
Did You Know...
In the movie Clear and Present Danger, CIA agent Jack Ryan (the character played by Harrison Ford) secretly orders a CIA hacker to find the username and secret password of another CIA agent whom Ryan suspects of treachery. The hacker succeeds,
enabling Ryan to read incriminating memos stored in computer files by the dirty CIA guy. All of that is technically accurate and possible, including the fact that the CIA probably knows how to look at anybody's files. (I'm feeling a little paranoid.)
What's not accurate in the movie is that when the bad guy discovers Ryan snooping, the bad guy erases the memos from the computer while Ryan is looking at them on his computer screen. Computer networks don't let you erase files that are in
usenot even the CIA's network_not even Harrison Ford's network.
Not being the primary users of most computers accessed through Telnet, Internet users have no username or password for each individual computer system. So the Telnet computer systems have two ways of letting Internet users get on board:
The first time the user telnets to the system, the system displays on-screen questions that ask the user to fill in some personal information and sometimes to choose a username and password to be used from that time on.
The Telnet system has a special usernameusually something like guest, visitor, or newthat can be used by visiting Internet folk. Most such systems display a message as soon as a new user telnets to them, listing what the guest username is
and how a visiting user should go about signing on.
In either case, the computer systems typically give Internet users the most restrictive security setting, allowing them access only to the most public information available on the system and keeping them out of private information and services that may
share the same computer.
Did You Know...
Internet users trying to hunt down a Telnet site for a particular purpose can use Hytelnet, a directory service that provides menu access to lists of Telnet sites, along with other helpful information about using Telnet.
Users of Telnet are vexed in yet one more way: terminal types. Again, because the various computer systems were designed primarily for their local users and not for everybody on the Internet, their methods for displaying information on-screen may be
specifically tailored to a particular type of computer terminal or workstation. On other types of terminals, the displayed words may come out garbled.
Internet users get around this problem with terminal emulation software that teaches their computers to mimic the terminal the Telnet system wants. Even so, this is one more inconsistency that makes using the Internet trickier than using a commercial
online service such as CompuServe or America Online, where everything looks and acts the same.
Many Telnet sites try to help users with this problem. And why shouldn't they? They've gone to the trouble of making themselves available to Internet users; they might as well smooth the path a little. The help available comes in several forms:
"Help" may appear as a choice on one or many menus, as may other words (perhaps "About this Service") that offer users a way to get information about using the system (see Figure 7.2).
A Help command may be available. When the system displays a menu, sometimes the user can enter a Help command (by typing help or sometimes just ?) instead of the number of a menu item. Doing so usually displays a menu of choices that lead to
screenfuls of information about the system.
Computer files containing general information about the systemeven entire user's manualscan often be copied from the system. Users can copy the files, read them on the screen or print them out, and then return to the system with the
know-how to use it. In addition to manuals, users may find Frequently Asked Questions (FAQ) files, described later in this chapter.
Figure 7.2. A help item (the top item in the left-hand column) on a menu in FedWorld, a database of Federal government information. To get help, the user presses B.
Most systems accessible through Telnet are overseen by one or more system operators, or sysops. Many systems display the name and e-mail address of the sysop when the user signs on, or they offer menu items that lead the user to a facility for
communicating with the sysop. Sysops are busy people, and they're paid to assist the primary users, so they usually don't like answering zillions of questions from Internet peopleespecially when the answers are available through help items or other
methods that don't involve the sysop. When all else fails, however, Internet users can approach the sysop and almost always get the answers they need.
Did You Know...
How bugged can sysops become when users ask dumb questions that they should have looked up on their own? Among the many common abbreviations used by Internet folk to keep their messages brief is this one: RTFM.
It stands for "Read the fine manual!" (That's the polite version.)
Systems available through Telnet include:
The Agriculture and Nutrition database at the University of Pennsylvania.
The Earthquake information system at Washington University.
CARL, a database of Colorado library catalogs, book reviews, articles, and more (see Chapter 2).
A thought-for-the-day service from Temple University.
Chess games and the oriental strategy game, Go (see Chapter 8).
NASA's National Space Science Data Center.
A history database at the University of Kansas.
The Concise Oxford Dictionary at Rutgers University.
A database of information about alcoholism and substance abuse at Dartmouth.
The Library of Congress catalog, through the University of Minnesota.
A bulletin board at the American Philosophical Association.
Many university information systems and their libraries.
Really Curious?
Much of the good stuff on the Internet is accessible only through Telnet. Increasingly, however, users can get to the resources and services on other Internet computers through special facilities that hide the differences and make the various
computers seem as though they all work the same way, or nearly so.
For more, see "They Burrow with Gopher" and "They Browse the World Wide Web" later in this chapter.
Computer files are available all over the Internet, and they contain everything that can be stored in a computer file:
Reports, books, and other texts
Software programs (shareware and freeware)
Photographs, drawings, and other pictures
Video and sound clips
Did You Know...
The bigger a computer file is, the longer it takes to copy over the Internet and the more space it takes up on the computer that stores it. To alleviate that problem, many large files on the Internet are compressed; that is, they have been processed
by a special program that makes them smaller without losing any of the information they contain. Users can copy compressed files in a fraction of the time the same file would require uncompressed.
The file can't be used in its compressed state, however. After copying, the user must decompress the file to return it to its original, bigger form. To decompress a file, a user needs a software program capable of undoing the particular compression
method applied.
Fortunately, most files are compressed with one of just two or three popular compression methods. If a user has the tools to handle these, he or she will never find a compressed file that can't be set free.
There are four basic ways Internet users copy files from other computers on the Internet to their own:
They can save newsgroup messages that have files attached to them. Users can post any type of file on a newsgroup by posting a message and using an option in their newsreader software that attaches a computer file to the message, sending it out on the
Internet along with the message. Other newsgroup users then read the message, which usually describes the file attached to it. If they want to have a copy of the file for their own use, they choose a Save option in their newsreader software to copy the
file to their computer.
They can send and receive e-mail messages that have files attached to them. This works in roughly the same way as the newsgroup method, except that the file is attached to an e-mail message sent directly to the user.
They can Telnet to systems offering menu items that allow them to copy (download) files made available to the public.
Curious About the Word?
Downloading and uploading both describe the act of copying a file from one computer to another, through a network. When the recipient of the file initiates and controls the copying process, the activity is called downloading. When the sender is in
control, it's uploading. Therefore, when a user employs FTP to copy a file from the Internet to his or her computer, the user downloads the file.
You'll see the term download used generically to describe copying files from the Internet or another online service to a user's computer.
They can use a facility called FTP (File Transfer Protocol) to access other computers and copy files stored there.
This last optionFTPoffers the greatest breadth of information. A large subset of computers on the Internet are known as FTP sites. Many of these are also Telnet sites. What the user sees when accessing these sites, however, depends on how
he or she goes in: If the user goes in through Telnet, he or she sees menus for using the information services available there. If the user go in with FTP, he or she sees lists of files available for copying. As with Telnet, users are usually required to
sign on to the computer with a username and password. The exception is "anonymous" FTP sites; these are set up to allow anybody to copy files without identification. (Actually, the process isn't completely anonymous. The computer at the FTP site
still knows who the user is, thanks to behind-the-scenes communications between the user's computer and the FTP site. The advantage of the anonymous FTP site is that users don't have to remember passwords to get files.)
Did You Know...
Among the most popular files copied on the Internet are Frequently Asked Questions (FAQ) files, simple text files containing the answers to questions typically asked by new users of the newsgroup, FTP site, or other resource where the particular FAQ
file is located.
FAQ files have two main goals. First, they bring new users up to speed quickly so they can use the resource productively. Second, they prevent new users from annoying the other users or the sysop with the same dumb questions asked repeatedly. Upon
venturing into a place they've never visited before, savvy Internet users like to find, copy, and read the FAQ file, if one exists. It makes them productive more quickly and also saves them embarrassment.
Typically, the lists of files at an FTP site are organized in groups called directories (see Figure 7.3). Directories can contain lists of other directories, each of which can contain a list of still more directories. So it can take some effort to plow
through the lists and directories to locate a particular file.
Figure 7.3. A list of files available for copying, as seen by an Internet user through FTP.
Did You Know...
A file is not a file is not a file. Different types of computers use different types of computer files, and because many different types of computers are on the Internet, not all files available for copying will be useful on any particular computer.
As a rule, text files are OK. There are only minor differences among the ways different computers store text files. Also, FTP automatically makes minor adjustments to text files to correct for those differences. Thus a user can use FTP to copy a text
file from anywhere on the Internet (say, a nice book from Project Gutenberg) and be reasonably certain that he or she will be able to read it (or print it).
Other types of filesespecially those containing software programswill be useful only on the computers for which they were created. For example, a software program written for a Macintosh won't run on a PC, so there's not much point in a PC
user copying it. Also, certain types of files can be used only with certain software. For example, the photographs and video clips available on the Internet require a program capable of displaying those types of files. Such programs are sometimes called
viewers and are part of the Internet user's software tools arsenal.
Sometimes the names of the directories and files will help a user find what he's looking for, but more often, they're cryptic. Many FTP users don't go fishingthey use FTP only when they know exactly what they're looking for and where to find it.
There is a facility that makes finding and copying files through FTP easier. Affectionately named Archie, the facility finds files available through FTP that match a name (or part of a name) supplied by the user.
When a user has at least a vague idea of what the desired file is called, he or she accesses a computer called an Archie server. The user's access provider may have an Archie server; if not, any user can Telnet to any of several Archie servers. The
user then types all or part of the filename and puts the Archie server to work. (The user can, in fact, tailor the search in several ways to make the search more accurate.) Archie searches a group of lists containing the names of files at various FTP
sites, and if successful, it shows the user where to get the desired file. The user can then use FTP to access the FTP site and copy the file.
Really Curious?
To see a picture of an Internet software tool that makes using Archie easier, see Chapter 5.
There are, in addition to Archie, other Internet facilities that make copying files easier. They take care of the FTP steps behind the scenes and offer the user an easy-to-follow set of menus. These facilities include Gopher (described below) and the
World Wide Web (described later in this chapter).
Menus make using an Internet resource easierafter the user makes his way to the resource. The challenges of finding a resource, getting onto it, and figuring out the peculiarities of its menu and command system conspire against all but the
bravest Internet users. But what if there were a system that allowed a user to find a resource, get to it, use it, and even copy files, all from a fairly consistent, easy-to-use set of menus? That's the idea behind Gopher, which along with Mosaic has made
the Internet much easier to use and in doing so has opened up the Internet to a new group of users.
Named for the mascot at University of Minnesota where it was developed, Gopher is a system of menus that allows users to "browse" for information simply by moving through the menus (see Figure 7.4). The beauty is that Gopher's activities are
spread across a wide range of Internet sites and resources, but it insulates the user from the tasks of choosing an Internet site, using Telnet or FTP to get to it, signing on, and more. All that stuff is done behind the scenesor eliminated
altogether.
Instead, the user picks through menus of subjects, sites, regions, or other ways of breaking down the possibilitiesin effect, the user "burrows" for information (hence the other explanation for Gopher's name). Even upon arriving at a
specific resource, the user sees the same style of menus, which work the same way. All the resources that participate in Gopherspace (the catch-all term describing the sum of all the resources accessible through Gopher menus) have agreed to play by the
same rules to keep things simple.
Figure 7.4. A Gopher menu, seen through a Gopher software tool.
While moving around the menus within Gopherspace, a user may jump from one Internet resource to another without even knowing it. Gopher makes the collection of resources that support it (which today include a strong collection of universities and other
sites, but by no means all of the Internet) seem like part of one big, consistent, smooth service where everything works the same way.
Gopher is available to all Internet users, but it really shines for those who have software tools designed to take special advantage of it, tools like the one shown in Figure 7.4. A PC program that uses the Microsoft Windows environment, WinGopher
allows the user to burrow through Gopherspace by clicking the mouse on items of interest.
At the end of a browsing session, a user may find himself at a menu of computer files. If he or she wants to copy one, the user simply picks it from the menu; just as Gopher shields the user from the details of Telnet, so too it hides the FTP activity
required to copy the file.
Browsing is a great way to find stuff, but if you've ever tried to find one book in a big library by browsing alone, you know that it's not an efficient approach.
To solve this problem, Gopher has a companion tool, Veronica. Just as Archie helps users find files, Veronica enables the user to type a "search term" to find Gopher menus and items on a particular subject. There are several ways to search
with Veronica, but typically the user types one word or more for the search term. Veronica searches Gopherspace, finds all the matching menu items, and creates and displays a new menu listing the items that match. The user can then choose any item from
that menu.
Did You Know...
The name Veronica is an acronym for Very Easy Rodent-Oriented Net-wide Index to Computerized Archives; the Rodent is our friend Gopher. The obvious relationship between Veronica and the file-searching tool Archie is said to be a coincidence, but I
can't help wondering how many different names and terms the programmers had to experiment with before they happened to "coincidentally" come up with one from the same comic book. (Did they try "Betty" first? Or did they have a
preference for Veronica from the start?)
Gopherspace is made up of Internet computers that are set up to play by the Gopher's rules so that users can access resources easily. Gopherspace includes only a small subset of the whole Internet, but when the superset is as large as the Internet, a
small subset can be pretty big. There are hundreds of Gopher sites offering millions of documents, files, and other resources, and more sites and resources join Gopherspace regularly.
Another subset of the Internet is called the World Wide Web (also known as the WWW, or the Web). The sites on the WWW have also agreed to arrange their resources on menus and to make information "browseable" by subject or by site; but the
folks on the WWW take browsing a step further.
When a user looks at menus, documents, or other screenfuls of information on the WWW, the user sees various words highlighted in some way so that they stand out from the rest. The actual way the words are highlighted varies a little by resource and
depends on what type of software is used to access the WWWa number may appear next to the word or the word may be displayed in bold or in a different color. However they're shown, the highlighted words are called keywords (see Figure 7.5). Keywords
are doorways to information.
Figure 7.5. A WWW menu, with highlighted keywords that lead to related information.
A user chooses a keyword in much the same way that he or she might choose a menu item. When the user does so, a new screen appears with related information and perhaps still more keywords to choose from. Users find out what they need to know by reading
what's on each screen, then drilling down to more specific, related information through the keywords. Users can also easily "back out" one step at a time through the screens they've read, to choose a different keyword and start down a different
path. It's much like using menus, but far more powerful and flexible because it allows users to jump spontaneously from idea to idea. Every document can double as a menu to more documents.
Originally called hypertext, the keyword approach has recently been renamed hypermedia because the WWW is evolving into a source of multimedia informationincluding text, pictures, sound, and even video.
To take advantage of hypermedia, the user needs an Internet software tool that can deal with multimedia information. That's where WWW browsers come in. Several are available, including a program called Cello from Cornell University and Lynx from the
University of Kansas, which is currently the most-used WWW browser. A newer freeware program called Mosaic, however, has been getting the lion's share of the attention lately. Perhaps second only to Gopher, Mosaic has encouraged the press and everybody
else to rethink the Internet and consider its potential as a resource within the reach of novices. Mosaic isn't perfectit has technical limitations that restrict it to users who have a particular type of Internet connection. (Users with the wrong
connection for Mosaic can use other WWW browsers.) But it's catching on like wildfire among those who can use it.
ReallyCurious?
What makes the WWW special is its hypertext/hy-permedia features, and that's why people use it. But the WWW is hooked into the rest of the Internet in a way that allows users to treat it like a window to the whole thing. From the WWW, users can reach
Gophers, Telnet sites, FTP files, news-groups and more.
The WWW also functions as a doorway to the sites that make up a subset of the Internet called WAIS (Wide Area Information Servers). The computers in WAIS allow users to search for information not just by what's in the document name, but by what's
actually in the document. Users can type a few words and select one or more WAIS computers; WAIS will then find all the documents on those computers that contain those words anywhere within their text.
The other resources weren't built as part of the WWW, so they don't feature hypertext or hypermediaand of course, users can always get to them directly without going through the WWW. Still, the WWW presents easy-to-use menus that take a user
most or all of the way to a resource, which makes it a handy, all-purpose Internet starting point.
You can learn more about using the WWW to reach WAIS and other Internet resources in Navigating the Internet, described in Chapter 10 of this book.
Created by the National Center for Supercomputing Applications at the University of Illinois at Champaign-Urbana, Mosaic provides a graphical window to the WWW through which users can "point and click" with a mouse to choose keywords. Because
it can display graphics on the screen (it's available for several graphical computing environments, including PCs with Windows and the Macintosh), Mosaic can show on the screen little pictures (icons) that serve as keywords for accessing multimedia
information.
When a user selects an icon that leads to a multimedia item, Mosaic determines which type of software is necessary to play that item, then starts up the required program. For example, if the user selects an icon that leads to a sound clip, Mosaic
starts another program that is capable of playing sound clips. When the user has finished listening to the clip, Mosaic exits the sound program and returns the user to the WWW screen. If an icon leads to a picture, Mosaic starts a viewer program to display
it.
Really Curious?
Just as Internet users can search FTP sites with Archie and search Gopherspace with Veronica, they can use any of several new toolsincluding Lycos, WebCrawler, and WWWWormto search the WWW for whatever information they desire.
Figures 7.6 and 7.7 illustrate the power of hypermedia through Mosaic. The resource shown is a multimedia medical textbook created by the University of Iowa. The user opens the textbook, reads each screen, and uses keywords to jump to related
information at will. When an illustration is available to help the reader understand a concept, an icon appears on the screen, as shown in Fig-
ure 7.6.
When the user moves the mouse pointer to an icon and clicks the mouse button, Mosaic starts a viewer to show the full illustration, as shown in Figure 7.7. (Notice that the icon in Figure 7.6 is a miniature version of the full illustration shown in
Figure 7.7.) When the user finishes looking at the illustration, Mosaic closes the viewer and returns to the screen shown in Figure 7.6.
Figure 7.6. A Mosaic screen featuring hypermedia icons.
Figure 7.7. The picture displayed after the user selects an icon, shown through a viewing program automatically started by Mosaic.
Did You Know...
Mosaic can tap into other Internet resources through the window of the WWW. Mosaic can be used to browse through Gopher menus, do searches with Veronica, find and copy files with Archie, and more. A growing number of people make Mosaic their
all-purpose Internet tool.
Internet users rely on a range of tools and techniques for digging up informationsome are easy, some aren't. Among the research tools and facilities making the Internet both easier and more powerful are
Gopher, a system of easy-to-use menus.
Veronica, a tool for searching through Gopher menus.
Archie, a tool for locating and copying specific files.
Mosaic, a tool for finding and displaying the hypermedia resources on the World Wide Web.
Other Internet research facilitiessuch as Telnet and FTPcan require more skill and patience. Most folks, however, find the effort rewarding, given the great depth and breadth of resources the Internet provides.
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