DVD initially stood for Digital Video Disk but now stands for Digital Versatile Disc. Like a CD, DVD is an optical storage system for read-only, recordable, and rewritable applications. But, being similar to a CD in many ways, DVD is considered to be a CD future replacement.
Figure 4-17. Comparison of the main features of the CD and DVD discs.
|Substrate diameter/thickness (mm)||120/1.2||120/1.2|
|Sides||1 or 2||1|
|Layers per side||1 or 2||1|
|Capacity (GB)||4.7, 8.54, 9.4, or 17||~ 0.7|
|Track pitch (micrometers)|