What is the difference between DVD-R/RW, DVD+R/RW, DVD-RAM and DVD+/-R DL?
Originally posted on WIBC.com on 01/24/2011
DVD stands for Digital Versatile Disc, the suffix of -R,-RW, +R and +RW represents the different type of recordable format currently available in the market. DVD Recordable format consists of, but not limited to the following:
DVD-R (pronounced “dash R” not “minus R”) is currently managed and supported by the DVD Forum. It’s support mostly consists of hardware manufacturing leaders including Pioneer and Apple. Originally designed for professional and commercial use, known as DVD-R for Authoring use or Authoring type, it was later made available to mass public market for consumer home use, known as DVD for General use or General type. DVD-R discs utilize organized dye that reacts to 650-nm laser used in most home DVD players. A 4.7GB DVD-R media can store up to 2 hours of high quality video and any additional audio tracks, special features, navigation menus as well as subtitle and any other special features that the DVD composer has created.
DVD-RW: The re-writable version of DVD-R media using phase changing alloy dye, enabling the content of DVD-RW to be written, erased, and re-written over and over for a limited amount of time. Most manufacturers claim over 1000 times re-writable with approx 60 years of storage life, however most users found DVD-RW have a relatively short media life due to excessive scratches, which is unpreventable if it is frequently used, resulting an unreadable disc. With that being said, it is highly recommended that any data, video or music you wish to store for long term to be stored on DVD-R write once media because of the more stable organized dye used.
DVD+R: currently managed and supported by the DVD Alliance. It’s support consists of power software giants including Microsoft, hardware manufacture giants such as Sony, HP, and Dell, just to name a few. With similar features as to DVD-R format, DVD+R is however designed to write data differently.
The DVD+R format uses organized dye that also utilize the 650nm wavelength, in addition with higher-frequency wobbled groove to eliminate linking sectors and options such as no-defect management.
You might ask what does this all mean? It simple means DVD+R format writes a more DVD player friendly data to ensure high compatibility.
DVD+RW: As you may have already guessed, DVD+RW is a re-writable variation of DVD+R format. However I cannot stress enough that DVD rewritable media, regardless of format; are not meant for long term archival/storage.
DVD+/-R DL: Also known as DVD+/-R Double Layer or Dual Layer. With 8.4GB of storage capacity, it is the most wanted media on a consumer’s list. To understand how DVD+R DL works, think of your DL recordable media as a 3 layer sandwich, with 1 layer of acrylic, 1 layer of organic dye, another layer of acrylic, another layer of relatively clear dye and finally enclosed by last layer of acrylic. How is this different from Double sided DVD-R? This simply means you do not have to flip over the disc to record the second side. Double Layer media means two side combined into 1 making it 2 layers of recording face on a single side.
DVD-RAM: Also known as DVD Random Access Media. Another format supported by the DVD Forum; it has many great features for data storage, however are not suitable for video storage. The main advantage of DVD-RAM media is due to the way the media is designed, data can be randomly stored, erased and re-written over; much like how your hard drive works. To better illustrate, think of writing a DVD media as writing on paper, when you write on DVD±RW media, you need to write the whole essay, and when you make a mistake or would like to make changes, you would need to toss the page to start with a new one (DVD±R) or erase the whole page and start from the beginning (DVD±RW). But with DVD-RAM you are writing on paper with pencil, when ever you wish to make changes, simply erase the word or paragraph and write over it.
“If DVD-RAM is so great why are DVD±RW more popular?” you might ask. Most DVD player can not read DVD-RAM media, and according to market studies, most DVD recordable medias are used for video purposes. Also, DVD-RAM is generally 3-4X more expensive than DVD±RW Media