standard, which has just one side capacity equal to 4 times the PD, DVD - It was possible to read and write PD in the RAM drive. However, in the summer of 2000, compatibility with PD was not taken into consideration when creating DVD-RAM version 2.0, which has the same with 4.7 GB standard capacity as other DVDs. At this point PD drives and media effectively disappeared from the market. External links Computer-related introductions in 1995 120 mm discs Japanese inventions