Well, quite a few, but I will explain the most important differences. DVD-R is more compatible with dvd players (in general), while DVD+R is far superior for data backup. Also, DVD+R is the closest format to an actual pressed DVD. Currently, DVD+R is up to 8X speeds, I am not sure about DVD-R, but I think at the moment, all a consumer can get is 4X DVD-R's (although 8X is already planned). DVD+R's can also have the booktype changed on the disk before burning, this means that you can basically burn a DVD+R as a DVD-ROM by using software that tells your burner to do so (compatibility with dvd players goes up a lot!). All in all, they are the same price right now, and if you get a burner that is dual format, go with DVD+R because you can bypass the incompatibilities with dvd players by changing the booktype.