This is an overview of the Recordable DVD formats for Set Top DVD Recorders and Computer DVD Burners; DVD-R, DVD-RW, DVD-RAM, DVD+R, DVD+RW.
Answer: There are five recordable versions of DVD: DVD-R, DVD-RW, DVD+R, DVD+RW and DVD-RAM. DVD-R and DVD+R can record data once, like CD-R, whereas DVD-RAM, DVD-RW, and DVD+RW can be rewritten thousands of times, like CD-RW. DVD-RAM is a removable storage device for computers and video recording. It has become widely used in DVD video recorders because of the flexibility it provides in editing a recording. The other two recordable format types (DVD-R/RW and DVD+R/RW) are essentially in competition with each other. There are many claims that one or the other format is better, but they are actually very similar. Many manufacturers now offer Set Top DVD Recorders and DVD Burners that record in both "dash" and "plus" format. Below is a brief look at each format.
A write-once format that is compatible with many existing DVD Players, Recorders and DVD-ROM drives. Can only be used in DVD Recorders and Burners that support DVD-R recording or multi-format recording (drives that record "plus" or "dash"). Holds 4.7GB of data or video. Typically, it can hold 2 hours of MPEG-2 video on standard (SP) speed setting.
DVD-RW is the re-writable version of DVD-R. It allows for approximately 1,000 re-writes before it is used up. In general, DVD-RW discs are slightly less compatible than DVD-R. Can only be used in DVD Recorders and Burners that support DVD-RW recording or multi-format recording (drives that record "plus" or "dash"). Also holds 4.7GB of data or video.
Another write-once recordable DVD format developed seperate from DVD-R. These discs are basically the same as DVD-R discs. They hold 4.7GB of data or video and are compatible with most DVD Players and DVD-ROM drives. They can only be used in DVD Recorders and Burners that support DVD+R or multi-format recorders.
The re-writable version of DVD+R. It can record approximately 1,000 times. They also hold 4.7GB of data or video and must be used in DVD+RW compatible Recorders and Burners or multi-format recorders.
DVD-RAM comes in two varieties and storage capacities. These discs come in both cartridge and non-cartridge varieties and come single-sided or double-sided. Offered by only a few manufacturers (Panasonic, Toshiba and a few other minor ones), DVD-RAM is useful if used like a hard drive. Because it supports and incredible 100,000 re-writes, you can use the disc to record TV shows, view them and then re-write over them many times. Single sided discs hold 4.7GB, double-sided 9.4GB, allowing for longer recording times. DVD-RAM is the least compatible of the 5 recording formats, and is typically used for recording and playback in the same Set Top DVD Recorder.
Final Thoughts When choosing a format to use, keep in mind that DVD-R/RW won't record in a DVD+R/RW recorder or burner, and vice-versa. This is not an issue when using a Multi-Format recorder or burner, and most DVD players and DVD-ROM drives will read either format.