Significance

• Consumers need to know the format of DVDs they use since different types of equipment require different types of discs. If the incorrect kind of DVD is used, the equipment may not play it correctly or at all.
  
  

Function

• DVD formats identify what kind of functionality a disc has and what types of equipment a disc will work with properly. Manufacturers select their preferred DVD format(s) for the equipment they produce.
  
  

Types

• There are six standard DVD formats: DVD+R, DVD-R, DVD+RW, DVD-RW, DVD-RAM and DVD-ROM. Non-standard formats include DVD-D, DVD-MP3, DVD-SVCD and DVD-VCD.
  
  

Recording Features

• DVDs fall into two primary categories. The first type can record data only once (DVD+R and DVD-R), while the second type can record and erase data many times (DVD+RW, DVD-RW and DVD-RAM).
  
  

Considerations

• A third DVD category is DVD-ROM, the first marketed standard DVD format. Like CDs, such disks are read-only, which means manufacturers burn data directly on them. They only play on compatible equipment.