OPTICAL MEDIUM is anon-volatile storage media that holds content in digital form that are written and read by a laser.These media include various types of CDs and DVDs.
These following forms are often commonly used:
-CD,CD-ROM,and DVD: Read only storage,used for distribution of digital information such as music,video and computer programs.
-CD-R:Write once storage,the data cannot be erased or written over once it is saved.
-CD-RW,DVD-RW,and DVD-RAM:Slow to write but fast reading storage；it allows data that have been saved to be erased and rewritten.
Advantages
-One optical disk holds about the equivalent of 500 floppy disks worth of data.
-Durability is another feature of optical media,they are able to last for up to seven times as long as traditional storage media.
