Optical storage media are direct access disks where data are written and read by ray technology. A large amount of data can be stored on an optical disk. CD (Compact Disk) and DVD (Digital Video Disk) are the common example of optical storage.
CD ROM:
A Cd-rom stands for compact disk read only memory. it is a hard plastic disk coated with aluminium that stores computer programs and files. The data stored on the CD-Rom cannot be changed by the user. The cd-rom is inserted in the cd-rom drive to read the information. It can store a large volume of data. i.e. up to 700mb (megabyte).
DVD:
DVD stands for Digital Video Disk. It is a type of read-only memory compact disk . It has huge storage capabilities. DVD-ROM disk can store 4.7 to 60 GB (Gigabyte) of data. It requires a special drive called DVD drive reads data at a faster rate.
