Untitled - TRS-80 Color Computer Archive

PersonalComputingDonald B. irivetteThe CD-ROMs Are ComingSix years ago, when I bought anIBM PC, it came with two state-ofthe-artfloppy disk drives. A floppyback then was single-sided andheld 180,000 characters of information—a lot, I thought. Two yearslater 180,000 bytes didn't seem likeso much and I replaced one of thesingle-sided drives with two halfheightfloppy drives—each capableof reading and writing double-sideddisks. At that point, the three driveshad a total capacity of 900,000 bytes.Last year I replaced the old singlesidedfloppy drive with a half-heighthard disk. Capacity: 20 million bytes.In November I upgradedagain. To my six-year-old computerI added a storage device that wasn'teven dreamed of in 1981. The Compact Disc-Read Only Memory, better known as a CD-ROM, has acapacity of half a billion characters.The CD-ROM player is smallerthan its musical counterpart, although the electronics are almostidentical. The unit I connected tomy PC is a free-standing SonyCDU-100, about the size of a telephone-answering machine. Sonyalso makes a reader that slips rightinto one of the PC's disk cavities.The computer compact disc isidentical to the 4.7-inch audio variety that records 60 minutes of music and has become the salvation ofthe record industry. Both record adigital "message" of zeros andones, called lands and pits, on oneside of the shiny aluminum platter.But unlike a floppy disk which hasdata recorded in concentric tracks,the CD records information on acontinuous spiral track similar to aconventional phonograph record.Unrolled it would cover more thanthree miles; on the disc it packs to adensity of 16,000 tracks per inch.Bacterium-SizedBitsThe high density is possible because the CD-ROM is an opticaldevice, not magnetic. The disc isrecorded at the factory with a laserby burning pits about the size of abacterium into the disc's surface.CD-ROM disc advantages include its low production cost—Sony says less than $1 per hundred—and its staggering capacity.The 550 million bytes available ona disc make the equivalent of 1500double-sided floppies or approximately 275,000 manuscript pages.One disc can store the equivalent of1000 books. And one disc could,and will, contain the telephone directories for an entire region of thecountry. Someday we may have anational telephone book recordedon three or four CD-ROMs. Onceyou understand the capacity of aCD-ROM, you begin to appreciatethe complexity of converting musicto a digital format: It takes theequivalent of 152,000 characters toproduce one second of music; anhour of music uses the entire halfbillioncharacters of a disc.One of the first home applications of CD-ROM technology is theAcademic American Encyclopediapublished by Grolier. This 20-volume reference set takes morethan two feet of shelf space in paperform, but fits nicely on a CD. Infact, the entire encyclopedia alongwith a huge index to speed upsearches uses less than 20 percentof the disc's capacity—four moreencyclopedia sets could be placedon this same CD.In order to use the encyclopedia, you first load the informationretrievalsoftware from a floppydisk into the PC. This works justlike loading any computer software. Once the retrieval program isrunning, you can use a variety ofsearch terms to find one, or dozensof articles on a topic. In less thanten seconds you can examine everyword in the entire encyclopedia.It's a delight to use. I enteredSURFING as a search word and infour seconds found there were 20occurrences in six articles: 1 each inthe Beach Boys, Hawaii, periodical,rock music, and skateboarding articles, and 15 in the article on surfing.By moving the cursor to one ofthese topics and pressing a functionkey—the program operates frommenus and function keys—I canhave the article displayed on myscreen. And by pressing anotherfunction key, I can have the articleprinted. I can even press a key andlook at an outline of the article—aby-product of the extensive indexingsystem.Special SearchesSearches that would be impossiblewith a conventional encyclopediatake only a few seconds. By modifying the search conditions to selectonly articles where the word BORNappears within five words of JAN 31,I looked for people with whom Ishare a common birthday. Thirtyseconds later the computer found 34notables, ranging from Andre Antoine,a French theater director bomin 1858, to James G. Watt, secretaryof the interior from 1981 to 1983.The Grolier Academic AmericanEncyclopedia sells for $199 and theSony CD-ROM player is about$900 (but as low as $600 in quantity.) Volume and competition aresure to bring these prices down.About 18,000 CD-ROM discs wereproduced in 1986; industry sourcesestimate that more than 12 millionwill be produced in 1990.And even now, it's technicallypractical to mix still-video, sound,and text on the same disk. Imaginean unabridged dictionary on a CD-ROM. Look up Beethoven, press akey, and hear a passage from hisFifth Symphony. Look up respiratory, press a key, and hear the correct pronunciation. Press anotherkey, and hear the word spoken inFrench. In German. In Chinese.