A CD-ROM is a pre-pressed optical compact disc that contains data. Computers can read—but not write or erase—CD-ROMs, i.e. it is a type of read-only memory.

What is CD-ROM in computer?

CD-ROM, abbreviation of compact disc read-only memory, type of computer memory in the form of a compact disc that is read by optical means. A CD-ROM drive uses a low-power laser beam to read digitized (binary) data that has been encoded in the form of tiny pits on an optical disk.

What is CD-ROM used for?

Used to store programs and data files, a CD-ROM holds 650MB or 700MB of data and employs a different recording format than the audio CD (CD-DA), from which it evolved. In the 1990s, the CD-ROM rapidly replaced the floppy disk for software distribution.