CD specifications are developed by two companies, Sony and Philips, the first majors in music field. Later, the computer industry and consumer electronics demand, increase gradually the many new specifications such as CD-ROM (CD-ROMs); CD-Is (interactive CD-ROM) 、 CD-RW (CD-rewritable) …etc. were recorded in Red Book, Yellow Book, Green Book, Orange Book, White Book and Blue Book.

According to specifications can be divided into the following types：
．Red Book(CD-DA)
Audio CD(Digital music CDs) specification。
．Yellow Book(CD-ROM & CD-ROM/XA)
CD-ROM(Compact Disc Read-Only Memory) specification。
．Orange Book(CD-R)
CD-Recordable(Recordable format)，which is an extension of Yellow Book。
．Orange Book II
Definition can be used to create music CD and CD-ROM CD driver。
．Orange Book III
Definition in specification of Re-Writable CD-RW。
．Green Book(CD-I)
Standard format of Compact Disc Interactive，called CD-I。
．White Book(Video CD)
Definition in specification of Video CD。
．Blue Book(CD Extra)
Definition in CD Extra (sometimes also called format of Laser Disc)。

DVD which the first name is called Digital Video Disc, but later its application is not only limited in audio-video presentation, so it's also called Digital Versatile Disc.

The origin of the DVD is to replace the CD, which is launched jointly by Sony and Philips. CD makes the emergence of traditional family stereo digital and derivative products, such as CD-ROM, Video and others widely used in various storage areas. But in the CD series of products into 3D multimedia era, the problem of inadequate storage capacity more completely exposed.

Especially in the movie playback, the CD can not be fully precise and capacity of a film which is distributors caused a great deal of trouble.

So in April 1994, eight major movie studios of the United States reach an agreement in joint development the audio-video presentation to the main purpose of the new generation of discs, which became the DVD now.

DVD minus series is enacted by the DVD Forum which is the worldwide organization that consists of the companies(enterprises) in DVD product R&D 、manufacturing and the hardware/software companies(enterprises) in DVD specifications jointly. The main aim is to enact DVD specifications, DVD develops well and advance DVD promotion, its disc types are as follows：

DVD Forum Definition
Specification	Ite	Conten
DVD-Book A	DVD-RO	ROM Digital Multi-DVD
DVD-Book B	DVD-Video	Digital Video DVD
DVD-Book C	DVD-Audio	Digital Audio DVD
DVD-Book D	DVD-R	Write-once Digital Multi-DVD
DVD-Book E	DVD-RAM	Reread-writable Digital Multi-DVD
DVD-Book F	DVD-RW	Rewritable Digital

DVD plus series is enacted by the DVD Alliance which is the worldwide organization that consists of the manufactures in PC 、 optical storage and electronic products jointly. The main aim is to study and enact compatible rewritable DVD discs and expect to integrate with PC and expendable electronic goods closely. Its main members include : HP, Philips and Sony. Its disc types are as follows：

DVD Alliance develops specification(patent)
Ite	Conten
DVD+	Write-once Digital Multi-CD
DVD+R	Rewritable Digital Multi-CD

Basically DVD-R/RW specifications is enacted by the DVD Forum , DVD+R/RW specifications is enacted by the DVD Alliance. Both of them are incompatible each other, such as the rival situation between the two teams, VHS(video tapes) and Beta. As for why are there two rival camps? The really is to be market share and royalties. Every DVD driver belongs to technology competence of the camp, DVD driver maker must pay royalties to the camp. Certainly, everyone rivals for priority in enacted specification makers.Their function is the same. It's difficult to conclusion which one is better. The performance in disc burning is related to driver module.

Region code is in order to protection of film copyright piracy and not to duplicate or broadcast in DVD Forum. There are eight regional area code in eight areas over the world, If the film that didn't belong to the local can't be broadcast. The categories as follows：

Regio	Countr
1s	America、Canada、East Pacific island region
2n	Japan、Eroup、Wast Asia、Arabian Peninsula、Egypt、South Africa、Greenland
3r	Singapore、Tailand、Vietnam、East Timor、Brunei、HongKong、Macao(Total fifteen countries)
4t	Latin America、Australia、New Zealand、South Pacific island region
5t	Africa、India Peninsula、Central Asia、Mongolia、The Soviet Union
6t	Chinese
7t	Retai
8t	Special places，ex：Airplain、criuse
DVD not to be limited in，the area code is LL or ree.

The disc which follow up specifications is thought the standard disc in general manufactures. According to the definition of specifications, re-writable times as following,
CD-RW can be rewritten 1000 times
DVD-RW/+RW can be rewritten 1000 times
DVD-RAM can be rewritten 100,000 times

There are many reasons, as following,
．A disc quality is less
．Breakdown and laser decay of Burners(driver)
．Compatibility is not good enough between burners(drivers) and discs
．O/S of PC or laptop is unstable or resource is inadequate.
．Unusual and conflict in software program
．A transmission line of hardware doesn't contact(access) well
．Above-mentioned frequently, the reason of unusual issue is that compatibility is not good enough between
burners(drivers) and discs in widespread use. You can refer the compatibility information via RiTEK official
website or refresh firmware to improve it. If the unusual issue were in O/S or hardware side, we would
suggest to retry by other burners(drivers) to clarify the reason of issue. Reminder: Avoid inadequate
resource and replicated failure , please only start the applications which use in replicating.

Because discs and burners(drivers) have to match each other, the compatibility issue appears on using. Burners(drivers) can't bring the highest speed when replicating, so the compatibility has to be solved between discs manufactures and burners(drivers) makers each other. One of reasons in compatibility issue is in firmware of burners(drivers) . The dominance of update(fresh) firmware is burners(drivers) makers and the new firmware will be made known to public in irregularly scheduled by burners(drivers) makers to improve compatibility issue. You can refer the compatibility information via RiTEK official website or refresh firmware to improve it.

There are many reasons, as following,
．A disc quality is bad
．Breakdown and laser decay of burner(driver)
．Compatibility is not good enough between burners(drivers) and discs
．O/S of PC or laptop is unstable or resource is inadequate.
．Setting system transmission mode is error
Above-mentioned frequently, the reason more happened in setting system transmission mode error. Presently, most of the interface of burners(drivers) is IDE and its transmission mode have PIO mode and DMA mode system. System will be abnormal while using PIO mode automatically in transmission mode and the replicate time is long. On the other hand, it will be replicated normally in DMA mode.

．Generally, video/audio mode disc can be played in player. User has to choose video/audio mode to replicate in
PC. If user used file mode to replicate, it would happen a compatibility issue and can't play.
．After replicating by Recorder or HandyCAM, please remember to run finalizes action. The finalized disc can be
played in other player.
．If the compatibility were not good enough between burners(drivers) and discs, the compatibility issue would
happen in other burners(drivers) .

The capacity of DVD Minus series explains clearly in DVD Minus specification. In general calculation, 1K = 1000 ， 1M = 1000000 ， 1G = 1000000000. Computer calculation is different from general calculation. Computer calculation is calculated by Binary. 1K = 1024 bytes ， 1M = 1024*1024 bytes ， 1G = 1024*1024*1024 =1073741824 bytes

The capacity of disc is showed by general calculation, the relation as following,
4.7GB= 4700000000B / 1073741824 = 4.377GB
Actually, the capacity of disc is 4.37GB in a computer.

Generally, the disc type and its manufacture will be marked on surface printing side. If it isn't showed on, user can use the Nero CD-DVD Speed and Nero Info Tool software that Nero enclosed. User can get the disc type 、the manufacture and the region code, but a few special disc can't be got related information.

Sensitivity is different from every blank disc with burners(drivers) laser. Burners(drivers) will find the Walking Optimal Power Control(WOPC) to match the blank disc before replicating. If it could not find it, error message would be pop. The frequently reasons as following,
．A disc quality is bad
．Breakdown and laser decay of burner(driver)
．Compatibility is not good enough between burners(drivers) and discs
Replicated failure will happen in using the older burners(drivers), and the reason is that laser decayed. You can refer the compatibility information via RiTEK official website or refresh firmware or change other burners(drivers) to retry for improve it.

．Why does have to start DMA while replicating?
．There are two transmission modes in pc and peripheral equipments. One is through CPU control to process
data transmission. The other is through technical chipset to process data transmission. In generally, DMA can't
through CPU control to process, and peripheral equipments will transfer data with memory each other. In DMA
mode is that peripheral equipments write data into hard-disc or read data from hard-disc by DMA. It isn't
through CPU operation, speed will be faster in system.
．The method to start DMA as following,
．1. In Win 98 / ME: To find your burner(driver) in 「Control platform」→「System」→「Hardware」→
「Device manager」and start DMA mode in 「Content」
．In Win 2000 / XP: To find 「IDE ATA / ATAPI Controller」in 「Control platform」 →「System」→
「Hardware」 → 「Device manager」and verify in 「Content」of 「Main IDE」and 「Minor IDE」
．External interface is not built-in transmission interface, and it doesn't provide access DMA mode directly.
．Chipset drivers that are some of motherboards provided. DMA mode will be upgraded to UDMA and controlled
directly by UDMA. When system is in UDMA mode, DMA chosen will be disappeared.

．In generally, using DVD-RAM has to install related drivers(programs), it's as hard-disc as free drag. In
burners(drivers), the function of DVD-RAM is the same as DVD+RW and DVD-RW. It's not recommended to
use because speed of DVD-RAM is slower.
．The specification of standard DVD-RAM is UDF and FAT32 format(outgoing specification is UDF format).
．Common software is INCD in DVD-RAM. After installing, it can be dragged access normally. If format is
inconsistent, choose drivers(burners) and click right key to find the menu that can format standard
specification. If it couldn't be used, it would happen software conflict. DVD-RAM will be recognized error,
while using start any application at the same time. Recommend: don't start any application while using DVD-
RAM.
．DVD-RAM driver is built-in WIN XP SP2, but it only support FAT 32 format. New disc has to be format, method
is that choose driver(burner) and click right key to find menu that can format to FAT 32 format and drag access
normally.

Compatible specification matches with the older players and DVD-RAM and DVD-R each other. DVD+R/+RW camp provides Book type function and change DVD+R/RW specification to DVD-RAM specification while setting before replication to improve compatibility between DVD+R/+RW and player in marketing.

D5 and D9 are listed of disc specification, DVD specification as following,

Disc Name	DVD-5	DVD-9	DVD-10	DVD-18
Sided / Layer	SS-SL Single Sided /	SS-DL Single Sided /	DS-SL Double Sided /	DS-DL Double Sided /
Capacity	4.7GB	8.5GB	9.4GB	17GB
Length	135min	240min	270min	480min

Specification for 8cm disc：

Disc Name	DVD-1	DVD-2	DVD-3	DVD-4
Sided / Layer	SS-SL Single Sided /	SS-DL Single Sided /	DS-SL Double Sided /	DS-DL Double Sided /
Capacity	1.4GB	2.7GB	2.9GB	5.3GB

．DVD+RW is marked by DVD Alliance and its usually showed on DVD+R/+RW disc. Please confirm disc
specification if it's RW series through related software.
You can refer the compatibility information via RiTEK official website to confirm compatibility status
between disc and burners(drivers).

The disc replicate time over 80 min is thought unconformable specification by burners(drivers). If user wants to get over-burn disc, they have to start over-burn function in software and burners(drivers) support over-burn function themselves. For example, user has to change over-burn time( disc capacity) in advanced preferences of Nero 6. The steps as following,
Nero 6 > Nero Burning ROM > File > Preferences > General > to choose Enable over-burn Disc-at-once burning(read the notes below) > Maximum CD size 99 min 30 sec 0 frm.

Nero software isn't certified, and every disc quality result with every burner(driver) is different from others. Test result just only be reference.

．Avoid placing under sunlight and exposing directly.
．Avoid placing near heat or excessive humidity place.
．In CD-R process, three layouts dye coater 、reflection(sputtering) and printing are at the same
side(information side). To avoid scraping dye coater and reflection(sputtering) brings out reading error.
Please place read side(negative information side) down, while placing disc on a table.
．DVD process is different from CD-R. Please place printing side down, while placing disc on a table.
．In order to keep well, please use damp-proof box.
．As the history of disc is not lasted long, its preservation is disputed. To avoid losing, please backup important
data once/per 2~3 years.

Hues of read-side disc vary greatly：
．Dye coater is one of disc process. Hues should be shared out on disc. If hues varied greatly, disc quality
would be less. Abnormal hues cause laser power of burners(drivers) unstable, speed-down or break off
while replicating.
Transmittance of disc is high：
．Reflection(sputtering) is one of disc process. Basically user can't see opposite view through disc. If you
could, disc quality would be less. It will affect replicating performance.

In purchasing disc, price and brand are for your reference only. Actually it's the most important in compatibility between burners(drivers) and discs. User often complains about why can't he replicate 16x speed with 16x-disc. The reason is in compatibility.
Suggest user：
1.Buy a few disc at once to check performance. If it got good performance, buy more.
2.Refer the compatibility information via RiTEK official website before buying

．Basically, it's undesirable to do so. There are some process difference in various products even the same
series. If update firmware to change burners(drivers) model, there is a certain risk that could easily lead to the
burners(drivers) fault. It's not recommended to use.

．Using unofficial firmware easily leads to burners(drivers) malfunction or replicated disc unable. Because it's
going to change burners(drivers) for replication setting, not replication of the original high speed-disc was that
high speed into recordable. Therefore, some issues are still not to be solved between the original
burners(drivers) and high-speed disc. At this time, unofficial firmware allows its high-speed replication, it's
easily lead to be abnormal between burners(drivers) and disc.