Short for, compact disc, read-only memory. A CD-ROM is a compact optical media disc used to store and play back computer data instead of digital audio. CD-ROMs have become a favorite medium for installing programs and distributing medium sized chunks of data, since they cost only slightly more to manufacture than floppy disks, and most major software applications would require several floppies to distribute. Today, there is CD-ROM media that can hold up to 650 megabytes of data (74 min. is the maximum designed capacity). The specifications for CD-ROM were first defined in the Yellow Book standard.