Digital Versatile Disc, short as the common called DVD, is an optical disc storage media format, it is typically used to play standard television, high definition movies, high-quality music and store high-capacity data.
DVD is similar to CD on the appearance; they are 120 mm in diameter or so. The most common DVD, that is, single-sided single-layer DVD, has seven times capacity to the VCD. That is due to the DVD light generated by the smaller optical pickup points (read the original spot size of 0.85μm down to 0.55μm), so in the same area the size of the disc (DVD and VCD's apparent size is the same), DVD data storage density can be improved.
Using Phased-changed Dual and partly MO technology, DVD-RAM has the least capacity of 2.58GB and to a maximum of 4.7GB. The first generation of DVD-RAM was available in June 1998, and version 2.0 was launched one year later. Its capacity has been upgraded to 4.7GB. Panasonic and Hitachi launched their product in 1999 to support for DVD-RAM and DVD-ROM separately.
Like CD-R, DVD-R is made through organic dye method. The majority of DVD readers and players support DVD-R, DVD-R capacity is only 3.95GB at the beginning, but expandable to 4.7GB later. The early DVD-R is divided into two categories: DVD-R (NYSE:G) and DVD-R (NYSE:A). DVD-R (A) is for the professional market, they use 635-nm laser to write data.
Formerly known as DVD-RW DVD-R / W, DVD-RW was launched in Japan Pioneer's DVD-RW home video recorder. Like CD-RW, DVD-RW can be rewritten more than 1,000 times. The latest DVD-RW contains a unique ID; you can copy protected DVD-ROM. Its capacity is 4.7GB.
Features: the advantage of good compatibility, ability to save data to DVD video format, can be played on DVD players. But the formatting takes a half hour.
DVD + R
DVD + R is a write-once variation of DVD + RW, DVD + R's and DVD-R staining is very similar, so part of DVD + R is also compatible with the DVD-R.
Features: DVD + R can write data with CLV format.
DVD + RW
Rewrite DVD + RW technology is based on CD-RW, available around the end of 2001. Philips, SONY, HP, Dell, Ricoh and Yamaha are supporting DVD-RW. DVD + RW recorders can read DVD-ROM and CD-ROM, it may also read DVD-R and DVD-RW, but can not read DVD -RAM. On the contrary, most of the DVD-ROM and DVD players can read DVD + RW.
In addition to burn DVD + RW, DVD + RW burner can also burn CD-R and CD-RW. The existing capacity of DVD + RW is 4.7GB each side.
Features: Easy to use and improved the compatibility with DVD-RW drives. It can be formatted from the beginning of burning. And a minute later it can start recording data. DVD + RW disc supports two recording formats, namely Sequential Video Acess CLV format, and Random Acess the CLV format. It no longer support DVD-R and DVD-RW specification discs.
DVD Multi / DVD Dual
DVD Multi and DVD Dual are the productions derived in the above specifications. DVD DUAL burner has surpassed the recording threshold of a single specification of the DVD + RW or DVD-RW; they can burn two sizes of DVD + RW and DVD-RW DVD discs. And because of the flexibility design of the chip, it can be adjusted easily in the design even some changes emerged, thus avoiding the waste of time and resources on search and development.
DVD Multi Features: Integrated DVD-R/RW and DVD-RAM
DVD Dual features: integrated DVD + R / RW and DVD-R/RW
The difference between DVD-R and DVD+R
Now the DVD burners on the market provide support for both DVDs. Generally speaking, DVD + R are typically for the burning speed and support relatively better on the burner. And most of the DVD + R disc in the market is cheap and has good quality.
The DVD-R is characterized by good compatibility, if you want always to use the old DVD drive, PS3/PS2 like games, or play on the DVD players, DVD-R is recommended because the devices support DVD-R better than DVD + R. So if you are prepare to burn Xbox 360 games or copy Wii games, the DVD-R can be a correct choice.
In general, DVD+R discs are proposed to store data; if it is audio and video applications, it is recommended to use DVD-R discs. Both of them have advantages and disadvantages, but not absolute.