DVD stands for Digital Versatile/Video Disc, DVDR stands for DVD Recordable and DVDRW for DVD Re-writeable. If you're familiar with regular audio/music CDs or regular DVD-Video discs, then you will know what a recordable DVDR/W looks like. A recordable DVDR/W stores up to 2 hours of very good quality DVD-Video, including several audio tracks in formats like stereo, Dolby Digital or DTS and also advanced menu systems, subtitles and still pictures that can be played by many standalone DVD Players and most computer DVD-ROMs. If you choose to lower the video quality it is possible to store several hours video on a recordable DVDR/W using low bitrates and low resolution with video quality more like VHS, SVHS, SVCD, CVD or VCD. It is also possible to have up to 4.37* GB ordinary data or mix DVD-Video and data on a recordable DVD that can be played by most computer DVD-ROMs.

There are three competing DVD Recording standards, DVD-R/W and DVD+R/W have pretty similar features and are compatible with many standalone DVD Players and most DVD-ROMs while DVD-RAM has less DVD Player and DVD-ROM compatibility but better recording features.

DVD-R and DVD-RW
DVD-R/W was the first DVD recording format released that was compatible with standalone DVD Players.
DVD-R is a non-rewriteable format and it is compatible with about 93% of all DVD Players and most DVD-ROMs.
DVD-RW is a rewriteable format and it is compatible with about 80% of all DVD Players and most DVD-ROMs.
DVD-R/W supports single side 4.37 computer GB* DVDs (called DVD-5) and double sided 8.75 computer GB* DVDs (called DVD-10).
These formats are supported by DVDForum.

DVD+R and DVD+RW
DVD+R/W has some "better" features than DVD-R/W such as lossless linking and both CAV and CLV writing.
DVD+R is a non-rewritable format and it is compatible with about 89% of all DVD Players and most DVD-ROMs.
DVD+RW is a rewritable format and is compatible with about 79% of all DVD Players and most DVD-ROMs.
DVD+R/W supports single side 4.37 computer GB DVDs (called DVD-5) and double side 8.75 computer GB DVDs (called DVD-10).
These formats are supported by the DVD+RW Alliance.

DVD+R DL
DVD+R DL or called DVD+R9 is a Dual Layer writeable DVD+R. The dual layered discs can hold 7.95 computer GB* (called DVD-9) and dual layered double sides 15.9* computer GB (called dvd-18).

DVD-RAM
DVD-RAM has the best recording features but it is not compatible with most DVD-ROM drives and DVD-Video players. Think more of it as a removable hard disk. DVD-RAM is usually used in some DVD Recordeers.

 

The DVD sizes can be a bit confusing. There are basically 4 different DVD+-R/W Sizes,

DVD-5, holds around 4 700 000 000 bytes and that is 4.37 computer GB where 1 kbyte is 1024 bytes* . DVD+R/W and DVD-R/W supports this format. Also called Single Sided Single Layered. This is the most common DVD Media, often called 4.7 GB Media.

DVD-10, holds around 9 400 000 000 bytes and that is 8.75 computer GB. DVD+R/W and DVD-R/W supports this format. Also called Double Sided Single Layered.

DVD-9, holds around 8 540 000 000 bytes and that is 7.95 computer GB. DVD+R supports this format. Also called Single Sided Dual Layered. This media is called DVD+R9, DVD+R DL or 8.5 GB Media.

DVD-18, holds around 17 080 000 000 bytes and that is 15.9 computer GB. DVD+R supports this format. Also called Double Sided Dual Layered.

* In the computer world is 1 KB data = 1024 bytes so 4 700 000 000 bytes / 1024 = 4 589 843KB / 1024 = 4482MB / 1024= 4.37GB.


DVD+R/W/DL and DVD-R/W exact sizes
DVD-R/W = 4 706 074 624 bytes ( 4488 MB )
DVD+R/W = 4 700 372 992 bytes ( 4482 MB )
DVD+R DL = 8 547 993 600 bytes ( 8152 MB )
 

DVD-+R/W write speeds (4.37 GB)
1x = around 60 minutes (1x read speed is 1.32MB/s(1 385 000 000 bytes/s) = ~57 minutes)
2x = around 30 minutes (2x read speed is 2.62MB/s = ~28 minutes)
2.4x = around 25 minutes (2.4x read speed is 3.17MB/s = ~24 minutes)
4x = around 15 minutes (4x read speed is 5.28MB/s = ~14 minutes)
6x = around 12 minutes (6x read speed is 7.93MB/s = ~9 minutes)
8x = around 10 minutes (8x read speed is 10.57MB/s = ~7 minutes)
12x = around 7 minutes (12x read speed is 15.85MB/s = ~5 minutes)
16x = around 5 minutes (16x read speed is 21.13MB/s = ~3.5 minutes)

DVD-+R DL write speeds (7.95 GB)
1x = around 104 minutes (1x read speed is 1.32MB/s = ~103 minutes)
2.4x = around 44 minutes (2.4x read speed is 3.17MB/s = ~43 minutes)
4x = around 28 minutes (4x read speed is 5.28MB/s = ~26 minutes)

* write speed time and read speed time is not the same because writing requires some extra steps and also does the faster writing above 6x usually use lower write speeds for some parts of the dvd. 4x DVD speed = 36x CD speed.


 

DVD-VCD
is basicly a VCD authored on a DVDR/W. DVD supports the VCD resolution but the audio has to be resampled to 48 khz. If the audio is resampled to 48 khz it is standard DVD-Video.

DVD-SVCD
is basicly a SVCD authored on a DVDR/W. DVD do not supports the SVCD resolution but it may anyway work and the audio has to be resampled to 48 khz like the DVD-VCD.

DVD-MP3
is MP3s burned on a DVDR/W but very few MP3 capable standalone DVD Players supports it because most Players verify DVDR/W as DVD-Video only.

DVD-ISO
is MPEG,MPG,VOB files burned on a DVDR/W without any DVD Authoring (making the vob,ifo files) but very few standalone DVD Players supports it because most Players verify DVDR/W as DVD-Video only.