Please define these DVD formats!?
 

Would someone please once and for all give a clear definition of all of these DVD formats and possibly why there are so many? Thank you.

DVD R
DVD-R
DVD+R
DVD RW

Any more I don't know about?

As far as I know DVD-R ; DVD R; and DVD+R are all the same thing. And with DVD-R's once you burn them the DVD is final, you can't go back over it and burn something else later. Also, I thought DVD RW and DVD+RW were the same type of discs in that you can go back over them and burn something else later if you want to. I could be wrong this is just what I always thought. If there is a difference I would also like to know. This may not actually answer your question its just my two cents.

The DVD Forum site offers answers to these and other questions.

Just incase people dont look other places for info.

DVD R: could be either +- as people dont tend to write it like that. Have to see it in context of a question or whatever.

DVD-R & DVD+R are NOT the same at all.
DVD-RW & DVD+RW are NOT the same either.

DVD-R & DVD-RW are the same family.
DVD+R & DVD+RW are the same family.

DVD-R can can come in DVD-R(G) General & DVD-R(A) Authoring formats. An authoring drive is required to write Authoring discs.

DVD+R drive cannot write a DVD-R and a DVD-R drive cannot write a DVD+R but there are now combo -+R drives that can write both types of media.

Just some added info,

Jake