There are several DVD formats available and it depends on the usage in order to determine which format is best for you. DVD is recordable media used to store data and/or backup computer data. The formats are DVD +R or -R and DVD RW. There is not much difference in the plus or minus ‘R’ as far as the disc capacity. It just a matter of preference. The RW format enables data on the disc to be erased. There is aslo DVD Dual-Layer media which doubles the disc capacity from 4.7 to 8.5. However in order to use Dual-Layer media your computer must be equipped with a dual layer DVD burner.