Question: What is the Difference Between Dual-Layer DVD and Double-Sided DVD?
Answer: Dual-Layer DVDs
Dual-Layer recordable DVDs come in two formats: DVD-R DL and DVD+R DL. These discs are only writable on one side of the disc, but contain two layers on that single side for writing data to. They can hold up to 8.5GB on the two layers. A DVD Burner must include support for either DVD-R DL ,DVD+R DL, or both to be able to write to the Dual-Layer discs.
Double-Sided DVDs
Double-Sided recordable DVDs also come in two formats: DVD-R and DVD+R, including the rewritable DVD-RW and DVD+RW. Double-Sided discs include a single layer on each side of the disc that data can be recorded to. These discs can hold about 8.75GB of data if you burn to both sides. DVD Burners that support DVD+/-R/RW discs can burn to Double-Sided discs, all you have to do is burn to one side, flip the disc like an old LP record, and burn to the other side.