Encyclopedia of Computer Science and Technology

322 multimediaa maximum of 640 kB of memory to hold the operatingsystem and application programs. A trick called “expandedmemory” was developed to allow data to be swapped backand forth between the 640 kB of usable memory and the1–2 MB of additional memory that became available in thelater 1980s.By the early 1990s, MS-DOS (then up to version 6.0) wasoffering an alternative command processor (called DOS-SHELL) that included some mouse operations, better supportfor larger amounts of memory, and the ability to switchbetween different application programs. However, by thattime Windows 3.0 was proving increasingly successful, andby 1995 most new PCs were being shipped with Windows.Many new users scarcely used MS-DOS at all. Finally, withthe advent of Windows NT, 2000, and XP, the MS-DOS programcode that still lurked within the process of runningWindows disappeared entirely.Further Reading“Information and Help with Microsoft DOS.” Available online.URL: http://www.computerhope.com/msdos.htm. AccessedAugust 15, 2007.Paterson, Tim. “An Inside Look at MS-DOS.” Byte, vol. 8, no.6, June 1983, 250–252. Available online. URL: http://www.patersontech.com/Dos/Byte/InsideDos.htm. Accessed February6, 2008.multimediaThe earliest computers produced only numeric output ortext (which itself actually consists of numbers—see charactersand strings). During the 1960s, CRT graphics (seemonitor) came into limited use, mainly on computers usedfor scientific and engineering applications (see minicomputer).However, most business computer users continuedto receive only textual output. A notable exception in the1970s was PLATO, a system of networked educational computerterminals that combined text, graphics, and sound. Itis this combination that became known as multimedia.While much less powerful than mainframes or minicomputers,the hobbyist and early commercial PCs (seegraphics card) of the late 1970s generally did have thecapability of producing simple monochrome or color graphicson a monitor or TV screen. The Apple Macintosh, firstreleased in 1984, was a considerable leap forward: Its userinterface was inherently graphical, with even text beingrendered as graphic bitmaps (see Macintosh).The arrival of the PC greatly encouraged the developmentof entertainment software (see computer games) aswell as educational programs. As PCs became more powerfuland gained hard drives and, by the late 1980s, CD-ROMdrives (see CD-Rom), it became practical to put extensivemultimedia content on systems in the home and school.One popular application has been encyclopedias, where thetext from the printed version can be enhanced with graphicssuch as photographs, maps, and charts. Besides beingmore compelling and easier to use than the printed version,multimedia encyclopedias can be updated easily throughannual upgrades, as well as allowing for linking to Websites that can further amplify or update the content.Encyclopedias and other educational programs alsobenefited from the use of links that the user can click withthe mouse, bringing up additional or related information orillustrations (see hypertext and hypermedia). Bill Atkinson’sHypercard, released for the Macintosh in 1987, provideda multimedia “construction set” that could be usedby nonprogrammers to create simple hyperlinked presentations,educational programs, and even games. Hypertextand linking are the “glue” that binds multimedia into anintegrated experience.Multimedia business presentations are now routinelycreated using software such as Microsoft PowerPoint, thenprojected at meetings. While simple presentations can emulatethe traditional “slide show,” one-upmanship inevitablyleads to more elaborate animations.Multimedia and Daily LifeDVD-ROM drives, with about six times the storage capacityof CDs, now make it practical to include video or evenfeature-length movies as part of a PC multimedia package.Meanwhile, the video capabilities of PCs continue to grow,with many PCs as of 2008 having 256 MB or more of videomemory. Combined with processors running at up to 2.5GHz, this allows computer-generated graphics to rival thequality of live video.However, the most important trend is probably thedelivery of online multimedia content (see Internet,online services, and World Wide Web). The widespreadmarketing of the Mosaic and Netscape browsers (see Webbrowser) in the mid-1990s changed the Internet from anarcane, text-driven experience to a multimedia platform.The ability to deliver a continuous “feed” of video and audio(see music and video distribution, online and streaming)allows content such as TV news reports to be carriedwith full video and radio broadcasts carried “live” withgood fidelity. Newspapers and broadcast outlets are increasinglyinvesting in online versions of their content, viewinga Web presence as a business necessity. As more Internetusers gain access to high-speed cable and DSL services (seebroadband), multimedia is becoming as pervasive a part ofthe computing experience as television is in daily life.Many facets of that daily life are likely to be affectedby multimedia technology in coming years. The ability todeliver real-time, high-quality multimedia content, as wellas the use of cameras (see videoconferencing and Webcam) has made “virtual” meetings not only possible butalso routine in some corporate settings. When applied tolectures, this technology can facilitate “distance learning”where teachers work with students without them occupyingthe same room (see distance education and educationand computers). Video “chat” services and immersive,pervasive online games have become important social outletsfor many people, with the experience becoming evermore realistic (see online games and virtual reality).Already, the concept of multimedia is becoming lessdistinctive precisely because it is so pervasive. Today’s Webusers expect to see images, video, and sound, whether aspart of a news story or an educational presentation, andmultimedia is appearing on all sorts of new platforms (see