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Getting more out of the worldwide web

1998; Elsevier BV; Volume: 351; Linguagem: Inglês

10.1016/s0140-6736(98)90304-x

1474-547X

John McConnell,

The Internet, and the worldwide web ("web") in particular, have been hailed as a new medium on a par with radio and television. Perhaps this is a claim too far, for the printed word, broadcast sound, and moving pictures existed long before anyone had the bright idea of delivering these experiences via extended computer networks. What is revolutionary about the web is its ability to deliver words, sounds, and pictures ("multimedia") through a single interface with the viewer, not the broadcaster, determining the programming schedule. In its early days (1993), web pages were seldom more than words and pictures with links to other pages of words and pictures. Now the technology has advanced to the point where the audiovisual medium can be integrated in, to the web as an, almost, seamless whole. The basic requirement for viewing a web page is the graphical interface called a browser. The browser turns web documents written in the hypertext markup language (HTML) format and their associated effects files (pictures, sound, animation) into a, hopefully, attractive page with hypertext links to other web documents. The two most popular web browsers are Netscape Navigator and Microsoft Internet Explorer, which are available for both Apple Macintosh and Windows formats and which in their more recent versions have integrated multimedia features. Most new computers come preloaded with one or other of these browsers. If you are using an older computer, the institution or commercial organisation that provides your access to the Internet should supply browsing software. New versions of Navigator and Internet Explorer appear frequently and can be down loaded from the Internet free of charge (see panel).PanelWhere to find web software Browsers Tabled 1BrowsersInternet Explorerhttp://www.microsoft.com/ieNetscape Navigatorhttp://home.netscape.com/Push servicesPointCasthttp://www.pointcast.comNetscape channelshttp://home.netscape.com/netcenter/cf/indexl.htmlMicrosoft channel guidehttp://www.iechannelguide.com/Plug-ins and helpersNetscape plug-in directoryhttp://home.netscape.com/comprod/products/navigator/version_2.0/piugins/index.htmlPlug-in placehttp://www.jumbo.com/pages/plugins/Adobe Acrobathttp://www.adobe.com/prodindex/acrobat/readstep.htmlQuickTimehttp://www.apple.com/quicktime/sw/index.htmlRealPlayerhttp://www.realaudio.com/products/player/index.htmlShockwavehttp://www.macromedia.com/Some multimedia sitesScience Channelhttp://channels.reed-elsevier.com/ScienceRTW/ElsevierScience/docs/welcome.htmEuroTransMedhttp://www.eurotransmed.nl/index.htmMicrobiology video libraryhttp://www-micro.msb.le.ac.uk/Video/Video.htmlExplore sciencehttp://www.ppsa.com/science/ Open table in a new tab Tabled 1BrowsersInternet Explorerhttp://www.microsoft.com/ieNetscape Navigatorhttp://home.netscape.com/Push servicesPointCasthttp://www.pointcast.comNetscape channelshttp://home.netscape.com/netcenter/cf/indexl.htmlMicrosoft channel guidehttp://www.iechannelguide.com/Plug-ins and helpersNetscape plug-in directoryhttp://home.netscape.com/comprod/products/navigator/version_2.0/piugins/index.htmlPlug-in placehttp://www.jumbo.com/pages/plugins/Adobe Acrobathttp://www.adobe.com/prodindex/acrobat/readstep.htmlQuickTimehttp://www.apple.com/quicktime/sw/index.htmlRealPlayerhttp://www.realaudio.com/products/player/index.htmlShockwavehttp://www.macromedia.com/Some multimedia sitesScience Channelhttp://channels.reed-elsevier.com/ScienceRTW/ElsevierScience/docs/welcome.htmEuroTransMedhttp://www.eurotransmed.nl/index.htmMicrobiology video libraryhttp://www-micro.msb.le.ac.uk/Video/Video.htmlExplore sciencehttp://www.ppsa.com/science/ Open table in a new tab In their latest versions, browser development has reached the point where the line between the browser and the rest of the operating system interface has blurred to the point of invisibility. The objects (eg, programs, wordprocessor documents, or web pages) that sit on the computer "desktop" can exist equally as well on the computer's hard drive, on the local area network, or on a server on another continent. All the "gee whiz" technology of the information age is wasted if you cannot find what you are looking for. Fortunately, in its early days enterprising computer scientists set out to research ways of indexing the web. These experimental search engines have developed from student projects into commercial organisations that finance themselves by incorporating advertising into their pages (see pages s7 and s16). A search engine consists of two elements, a "robot" or "crawler" that trawls through the pages of the web creating a huge index, and a program that compares a research request with the index and presents the results. Because the indexing and retrieval methods used by the various search engines vary, and often change, it is difficult to generalise about ways to conduct a search. However, each site gives on-screen help with search strategies. In addition, to get your explorations started, browsers usually have a search button that will present you with a list of links to the search engines. There is no need always to go looking for what interests you: with so-called "push" technology web pages can be sent to your computer without having to request them. An early player in this field was PointCast. With PointCast you customise the service to deliver only the type of news that interests you (eg, politics, world events, health, sport, weather, stocks and shares) and the appropriate pages are sent through the Intemet to your computer for viewing offline. If you have a direct connection to the Intemet via a local area network the pages may update whenever your computer has been idle for, say, 15 min; if your connection is via a modem, the pages may update just once a day. A recent PointCast initiative is to offer variations on the basic service targeted at professional groups, including healthcare professionals. Microsoft and Netscape have built similar push services called "channels" into their latest browsers. Channels covering an ever-growing range of subjects—including science news— are available, and once you have chosen to take a particular channel the most recent update can be found simply by clicking a desktop icon. However you receive web pages, they are increasingly likely to include pop-up windows, sound, and animation alongside the text and static pictures. These multimedia features may depend on built-in miniature applications written with the JavaScript, Java, or ActiveX (Internet Explorer only) programming languages (for definitions, see page s8). Alternatively, you may have to download and install a plug-in or helper application to enjoy multimedia. A plug-in opens within the browser, whereas a helper application opens the multimedia file within a separate window. Examples include the Adobe Acrobat reader, which displays documents in their original (ie, printed page) format, and the QuickTime video player. A helper application or plug-in usually opens once the whole multimedia file has downloaded; however, with "streaming" technology applications such as RealPlayer and Shockwave the file plays as it is delivered to your computer. The great advantage of streaming technology is that allows live coverage of events—eg, concerts, conferences, or sports—direct to your computer. If you try to download a file of a type for which you do not have the necessary plug-in or helper application, the browser will often display a message pointing you to a site where you can get the application. In addition, the Netscape web site has a facility that automatically updates the Navigator browser with multimedia plug-ins. Increasingly, what was a plug-in or helper application a few years ago is an integrated part of the browser now, and this trend is sure to continue. If you can listen to it on the radio or watch it on television, do so—because of limitations in network capacity the web cannot yet deliver the quality of experience of these older technologies. For the time being, the web is best kept for sound and vision that you could not access any other way. That PC with a 386 processor, 4 MB of RAM, and a 250 MB hard disk you sacrificed a holiday to buy in 1992 is just is not up to the job. Fortunately, the same investment (probably less) in 1998 will buy you a Pentium II or Power PC processor plus at least 32 MB of RAM, gigabytes of disk space, a sound card, speaker, and built-in modem, which should have you flying through the web.