DVD-RAM
Stands for "Digital Versatile Disc Random Access Memory." DVD-RAMs are writable DVDs that can be erased and rewritten like DVD-RW and DVD+RW discs. Unlike the other two writable DVD formats, DVD-RAM discs support advanced error correction and defect management. While these features slow down the maximum data transfer rate for DVD-RAM discs, it also makes the discs more reliable.
Early DVD-RAM discs required an enclosing cartridge, which meant they would not fit in most DVD players or DVD-ROM drives. Therefore, you would need a DVD-RAM drive to use DVD-RAM discs, as well as burn them. Newer DVD-RAM discs, however, can be used without a cartridge. These discs can be played in any DVD player that supports the DVD-RAM format. While the first DVD-RAM media could only hold 2.6GB on a single-sided disc, newer double-sided discs can store up to 9.4GB.