• Directory of Internet terms
  • Cd-rom — Abbreviation for Compact Disc Read Only Memory. A CD-ROM is an Optical Disc on to which data has been written via a laser - a process often referred to as "burning a CD": see Burn. A CD-ROM looks much the same as an audio CD, but can contain text, sound, pictures and motion video. Once written, the data on a CD-ROM can be fixed and rendered unalterable, hence the term read-only - but modern computers are usually equipped with a read/write CD-ROM drive that enables new material to be stored on a special kind of CD-ROM: CD-R (recordable) or CD-RW (rewriteable). It is worthwhile investing in a read/write CD-ROM drive for making backups and storing your own multimedia materials. Blank CD-Rs or CD-RWs can be bought from computer media suppliers at a relatively low cost. You can store data on CD-Rs using a read/write drive, adding to it until it is full, and then you can format the CD-ROM so that it is fixed and can be read by a standard CD-ROM drive. You can also store data on CD-RWs in the same way, but these discs can only be read by a read/write CD-ROM drive. The advantage of CD-RWs is that they can be erased and used over and over again, but now that the cost of blank CD-Rs has fallen to such a low level it is questionable how useful CD-RWs are. See Combination Drive, Digital Video Disc (DVD). See Section 1.2.1, Module 1.2 and Module 2.2.