CD/DVD

A CD (compact disk) provides 650-700 MB of storage. A DVD (digital video disk or digital versatile disk) has a capacity of 4.7 GB. CDs and DVDs are durable storage and have a higher tolerance for temperature fluctuations then hard disk, floppy disks, and tapes. They are unaffected by magnetic fields and dust and dirt can be cleaned off easily.The biggest threat is scratches.

CDs and DVDs come in several varieties:

• Read only (ROM) – permanent data stored during manufacturing

• Recordable (R) – A writable drive can store data but it can’t be changed

• Rewritable (RW) – can be changed many times, much like a hard drive but much

slower