There are five current formats for your recording pleasure...or displeasure. Keep in mind that the R stands for writing to the disk once, producing a non-erasable disk. The RW indicates the ability to rewrite to the disc, making it erasable.
DVD-R and DVD-RW, compatible with each other.
The DVD-RW supports two modes of recording — VR (video-recording) that allows editing away annoying commercials or poorly executed or unwanted scenes, and playable in the same DVD recorder and just Video, less complicated and more compatible with other DVD player and recorder formats.
DVD+R and DVD+RW, compatible with each other.
DVD-RAM, rewritable and erasable
The DVD-R or +R disks can be picked up at your local retailer, are the least expensive and can be played in most DVD players and the DVD drive on your PC. They however, require a formatting step that can take upwards to an hour on some machines, depending on the size of your video. This formatting allows the DVD to be compatible with other DVD players and keeps the video from being erased later. There are segments created when recording for easier navigation although the DVD-R and —RW do not support any manipulation of these segment markers and you cannot play around with the markers after the initial recording. With the DVD+R and +RW you will be able to add and change markers but with the +R media, these markers will be readable only by other DVD+R and +RW units. And note that without a hard drive, there is no way that you can record on and watch the same disk simultaneously in either the + or the - formats.
The DVD-RAM media are designed for Panasonic DVD players and your DVD drive on your computer. They are the same capacity as the other media, unless you use the double sided mode and in that case you get twice the viewing pleasure, up to 9.4 GB of space. There is no finalization necessary and you will be able to record one program while watching another on the DVD-RAM.
You may wonder if your recorded dance DVD will play on Aunt Bertha's DVD player. There is no guarantee unless it is the same make and model. Give it a try, and with newer DVD players there is a good chance that it will.