Final answer:
CD-ROMs and DVDs fall under the category of optical discs, which store data using physical alterations read by lasers.
Step-by-step explanation:
CD-ROMs and DVDs are examples of optical discs. These storage media use laser technology to read and write data. The data on these discs is stored in the form of tiny pits and lands, which a laser reads by interpreting the light reflections. Unlike magnetic tapes or disks, where data is stored magnetically, optical discs use these microscopic physical alterations in their surface to represent digital information. Optical discs have been crucial for the storage of audio, video, and data before other technologies such as streaming services became prevalent.