I used to read that DVD-ROM and DVD-RAM were not compatible with each other. Then you have DVD-RAM writers (such as Panasonic's LF-D03U External DVD-RAM) which specs mentions that it does read DVD-ROM + read/writes DVD-RAM... how to explain that? Also: are both DVD-ROM and DVD-RAM included in nowaday's multiple formats dvd drives? And since DVD-R, DVD+R, DVD-RW, and DVD+RW are writable formats, I guess they are all part of the DVD Ram format, is that right?

"Then you have DVD-RAM writers (such as Panasonic's LF-D03U External DVD-RAM) which specs mentions that it does read DVD-ROM + read/writes DVD-RAM... how to explain that?" Because the drive was engineered to do that. "Also: are both DVD-ROM and DVD-RAM included in nowaday's multiple formats dvd drives?" Some support this and some do not. "And since DVD-R, DVD+R, DVD-RW, and DVD+RW are writable formats, I guess they are all part of the DVD Ram format, is that right?" No. See this page for information on the different formats: http://www.webopedia.com/DidYouKnow/Hardware_Software/2003/DVDFormatsExplained.asp

Excellent concise and complete reply by GerryC!

Hold on now, DVD ram and rom arnt included together in drives, DVD ram is in the shape of a floppy disk, but a bit bigger, and rom is the shape of a cd. No way they are compatible together on computer drives. My Rig: 1040Mhz Pentium 3 OC'd at 1.2Ghz Aopen MX3WPRO-E mobo Intel 810 chipset Onboard Graphics Not sure how many MB 128mb RAM 120GB Maxtor Hard Drive My Old Rig: AMD K6 400Mhz

"Hold on now, DVD ram and rom arnt included together in drives" It is in some drives. For example: LG GSA-4163B and LG GSA-4040B