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There are six recordable versions of DVD: DVD-R for General, DVD-R for Authoring, DVD-RAM, DVD-RW, DVD+RW, and DVD+R. 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-R was first available in fall 1997. DVD-RAM followed in summer 1998. DVD-RW came out in Japan in December 1999, but was not available in the U.S. until spring 2001. DVD+RW became available in fall 2001. DVD+R was released in mid 2002.
Recordable DVD was first available for use on computers only. Home DVD video recorders (see 1.14) appeared worldwide in 2000. This FAQ uses the terms "drive" or "burner" to refer to recordable computer drives and the term "video recorder" to refer to home set-top recorders.
DVD-RAM is more of a removable storage device for computers than a video recording format, although it has become widely used in DVD video recorders because of the flexibility it provides in editing a recording. The other two recordable format families (DVD-R/RW and DVD+R/RW) are essentially in competition with each other. The market will determine which of them succeeds or if they end up coexisting or merging. There are many claims that one or the other format is better, but they are actually very similar. In 2003 many companies began making drives that could record in both "dash" and "plus" format.