We r&e;
Wkrdow on the Web Y:G-Ir view of the WWW is provided
As the vast amount of information on the Internet grows, THE MMMf PROlVllSESNEW WAYS to view its treasures.
S
by the browser - an easy-to-use, graphical interface that displays Web pages on your computer. The finr browser was developed in 1993 by Mark Andreessen, a ZI-year-old programmer at the University of Illinois’ NCSL Called Mosaic, it led to other browsers, notably Internet Explorer from Microsoft and Netscape Navigator from Netscape Communications.
Once you’re connected to the Web, your first question will undoubtedly be: with 150 million pages co choose from, where should I go? A variety of WWW directories and search engines are available to help you sort t,lrough the morass of information (see box). The favoured directory used by millions of people each day is Yahoo!, which organizes Websites by subject classification - you can either scrol! through these or use the Yahoo! search engine. Although this searches all the Yahoo! subject categories, it also
uperimposed on the Internet is a much newer service called the World Wide Web (www). Only 3 few years old, the Web already offers over 1.50 million addressable pages. Not only an information tool, the Web is becoming a multimediaexperience. In its next stage, the Web will increasingly become an integral part of the personal computer. A few basks Each computer tk.dt accesses the Inteinet uses P language for talking back and for, h called TCP/IP, the IP part determines how to get to other places on the Intemer; the TCP part determines how to take apart a message into small packets that travel on the Internet and then reassemble them at the other end. The WWW uses an additional language called the HyperText Transfer Protorol (HTTP). Any computer with this program running on top of TCP/IP is part of the WWW.
;rcFgformation building Web documents are written in H7Ml.z this ‘markup’ language describes such things as where paragraphs begin and where graphic images are to be placed. Most importantly, it describes where hypertext links are located within the documenr. These ‘hyperllnlw’ provide connections between documents, so rhat a simple click on a hypertext word or picture on a Web page allows your computer to stretch across the Internet and simply bring the document to your computer. Each compurer that has information another user wants is called a server: your computer is a client of the server. Of course, the Web is much more than a series of hyperlinks. Its multimedia capabilities provide access to video, audio and animation, and the ease of creating Web pages has revolutionized publishing [see the articles on Net Publishing (page 12) and Creating a Home Page (page 14)J.
These are all available as freeware, or are freely available for downloading a demonstration version that has no time limit on it (see software box on oaee 9). ?o;equest a Web page from another computer on the Internet you either click your mouse on a hyperlink or you type in the Uniform Resource Locator (URL) of the Web page. The URL describes both the protocol (HTTP for Web pages) and the address of the page or file you want (comprising rhe name of the computer and the name of the file). When you request a Web page, the HTML file for the page is sent to your computer together with each graphic image, sound sequence, or orher special-effect file that is mentioned in the HTML fife. Since some of these files may require special programming that has to be added ro your browser, you may have to download the program rhe first time you receive one of these special files. These programs are called helper applications, addons or ph@lns, depending on rhe program and the browser you use (see box).
to go and how to
simultaneously forwards your search request to six other leading search engines, which you can then link with. For a change, try ClNet’s search.com, which lets you try the Infoseek starch engine first, but also has links to AltaVista, Excite and several others. The !,ycos catalog contains over 10 million pages of Web information and an indexing funcrion rhat groups topics into broad categories. As you find sites you want to come back to, you can earmark them using the ‘bookmarks’ or ‘favorites function of the browser.
l
l
A search engine has two parrs: a ‘robot’ or ‘crawler’ that goes to every page, or representative pages, on the Web and creates a huge index; a program
that receives your search
request, compares ir with the entries
in thumbnail size that you can click on
in the index, and returns the results
and magnify. Moreover, they’ll have
to you.
updated and customized information
Most, if not all, of the major search
waiting for you when you magnify
engines attempt to do somethingclose
them, Turning on the computer in the
to indexing the entire text content of a
morning will become an adventure in
Web site. Once a site’spages have been
world happeninns and daily reminders,
indexed, the search engine will return periodically to the site ro update the index. Some search engines give special weight to words in the title, in subject descriptions and keywords listed in -%TML META tags, 10 the first words
In fact, push technology, or the idea that information can be served to you
on a page and to the frequent recurrence (up to a limit) of a word on a page. Because each of the search engines uses a somewhat different indexing and retrieval scheme (which is likely to be treated as proprietary information), and because each search engine can change its scheme at any time, it’s difficult to our-guess. Just follow each one’s directions on how to search. To avoid an overwhelming list of search results, remember to narrow your search by entering a short combination of keywords to he searched. Less frequently usedsearchresources includeV8rtntl~ (searchesgophersites), Archle (searches ftp sites) and WAIS (searches special WAlS databases). You can also search USENET newagroups.
even when you’re not around to request it, is already available from PointCast (http://wtvw.pointcast.com/) through Martmba’s Ca~tanct channels, and a numbrr of other sites.
Web pages now often include animated images or built-in calculators that are embedded in pages withour the need for special vlewefq these are commotdy written in Jstva, IavesCrlgt or AlveX programminy! languages. In Addition, the
Browsers of the future By the time you read this, the Web browser will be disappearing into rhe desktop. Netscape’s Constellation, a part of its new Communicator, as well as Microsoft’s Internet Explorer 4.0 and Windows 97, will put your desktop and the network together into a compurerinteractive workplace. Some things just happen to be in your computer; other things just happen to be 3000 miles away. Your newspapers, bank and an lnterner glossary no longer need be hookmarked; they can be visible objects Plugfnwhdgar @eaSon Adoba Acrobat
ufaet
CHIME
Chemical 30 imagery
M4wS6zd~nason~web Atta~sta0rtt4.x/~~.~sdfgftaI~111n,avay~sasrdr engine that usea a number of a3nputers opemthg In parallel l GINat’s seamh.conl (flupr//aoamh.com/) . Excita kmp://www.exc~ite.a vhlch also oRera a Sean% engine you can install on your own sita for local searches l Hot&t (hnp://mvw.hotbotoomA l Infoseekthaa://~.infoaeek.t%m/l l Lyws(llttp://ti.lyws.com/) .l We+Jcrwler(hap: l Mhoa~ uIUw//~.yatioo.aml/) You*II find many other specrarrted search engines list& in EeaySaamher2 (httnt//wmr.er3ysc~&ar.a~/ezZhtmb, l
l
computer rather than waiting until the entire sound file arrives; Shockwave or EnlIven movies;
three-dimensional scenes that you can explore. By 2001, people will think a lot less about the technologyitself and more about what rhey’re looking ar, or listening to, or submergedin. l
Dynamic HTML Withthe new Web desktopscome pages or presentationareasthat can change as you interactwith them- the appearance Site
Gmuh(c/text reader
http://www.edobe.com/pmdindex/ acmbat/readstep.hlrnl ~ttp://wx~.mdli.com/chemscepel chime/down\oad.htsnl CoolTalk Chat facility http$/vnwc.netscape.com/ Enlivan Stmaming video http://www.narrative.com/ GraphicComretter Converts image formats hap:/~Nww.infonnedusa.com/t/ graphicconv7.8.html Uve3D hnm//www.netscape.com/ 30 imagery http:/jww.apple.com/ QuickTime Motion video hnp://wow.realaudlo.com/ ReelAudio Stmeming sound http:/;wow.mocmmedia.com/ Motion video ShOckwave http://ccamecinfo.cca.quaensu.ca/ Sound Machine Netacapa sound MacSDistriuution/SoundMochine.html player for the Mac in general. all helper applications and plug-ins are free. One or two of tl.3 a:%~‘@ are sharevrare,whichcw~dr-mloadedfreslywiUltheunde~standingthattheuserwillser~d in a paymentlater. Eachof these comes with instructions about the con& ions OfU5e.
of the page may change or a small
AH&-s=---”
mcR/nmra*x-M item. This is generated using tbe JavaScript feature called ‘MouseOver’. Another new development is dynamic IiTMLz a page coded with dynamic KTML can have layers of information that can be peeledaway or disassembledand reassembledby the user. For example, a pagecould contain a successionof overlayingtechnical diagrams about a biochemicalstructure tbar becomemore detailed at the request of the met.
New users find the Web exhilarating, frustrating and sometimes exhausting. Asthey learn to use it, many usersfind rhat the Web can simply be a usehl rool to draw upon now and then; no need to surf. Then one day. a colleague tellsthem of a new site, and they find rhemselvesunder its spcl! again. The Web is like that.
Lowell Thrng (
[email protected])
is e fomer technical witerfor IeM and has an lnte0Iet
exprat&ian. &~.%~ryand ‘cybemacket reference’ siteat htto:/Nurtis.oom/