CD-ROM: A New Technology with Promise for Education. (1988)

CD-ROM: A New Technology With Promise for Education The compact disc made its initial entry into the consumer market as a medium for digitally storing and reproducing music. The same technology that is adding new excitement and quality to stereo music reproduction also holds considerable promise as a data publication and retrieval medium for educational purposes. When this technology is applied within a computer system, it is called CD-ROM (compact disc, read-only memory). This article describes the medium, points out some of the characteristics that make it suited for educational purposes, illustrates how it can be used in education, and concludes with descriptions of some of the currently available educational applications. What Is CD-ROM? CD-ROM is a data publication and retrieval medium for use with computer systems. The physical medium is like that of a compact disc for ordinary stereo systems. Data is stored as 3D pits on the disc--about 2 billion pits on a three-mile track. The surface is then sealed with a protective coating. A CD-ROM drive connects to a personal computer and reads data from a compact disc much as a floppy or hard disk drive reads data. Compact disc drives, however, use a laser beam to retrieve stored data, while both floppy and hard disk drives use a magnetic head. This virtually eliminates wear of the disc surface, thereby prolonging useful life almost indefinitely. CD-ROM discs and drives have a number of features that make them well-suited for educational settings. A tremendous amount of information can be stored on a compact disc. Each CD-ROM can hold approximately 550M of read-only information, or more than 150,000 pages of text. This is equivalent to the storage capability of 1,520 360K floppy disks or eight 70M hard disks. Storage capacity of this magnitude allows publishers to provide large databases, such as Grolier's Electronic Encyclopedia, on a single disc. It also provides sufficient space for enhanced sound, an important consideration in courseware development and delivery. CD-ROM discs usually conform to two important industry standards, the Philips/Sony Yellow Book specification, which addresses the physical characteristics, and the High Sierra standard, which covers file directory structure. If a disc conforms to these two standards, it should be readable on any manufacturer's CD-ROM drive. However, the information on most discs is still written for MS-DOS computers, so the majority of CD-ROM discs and drives available today require an IBM PC or compatible. Earlier this year, Apple Computer, Inc. announced a SCSI-based CD-ROM drive that works with Macintosh and Apple II computers. Version 1.2 of Apple's HyperCard software, released in May, supports this drive, and several disc publishers have already announced that they will support it, as well. A disadvantage of current CD-ROM technology is that data is read-only, meaning that the user cannot save onto the compact disc. Although this is an advantage for many educational applications because it eliminates the possibility of inadvertently erasing data, it is a serious drawback for others. The read-only limitation requires that current CD-ROM be considered a medium for publication of data rather than for user storage. There are some CD-WORM (write-once-read-many) drives that allow users to record data onto an optical disc, but the data can be recorded only once and cannot be altered or updated. Furthermore, CD-WORM discs are not the same size as the standard CD-ROMs and are not compatible with the rest of the compact disc evolutionary line. Nevertheless, they're well-suited for certain specialized situations in which users need to archive large volumes of data. Although today's CD-ROM users cannot write to their discs, this is expected to change soon. Several companies are working on read/write compact discs. …