What is the difference between DVD-R/DVD-RW, DVD+R/DVD+RW and DVD-RAM discs?
DVD-R and DVD-RW These 2 disc types were created by the DVD Forum ( see it at DVD Forum Site ). Both DVD-R and DVD-RW types generally come in the single-sided, single layer 4.7 GB capacity, which is roughly equal to 120-minutes of standard playing time. You can also now find 9.4 GB double-sided discs entering the market, although there are no players which will automatically play both sides of the disc without ejecting it and turning it over. Eventually, there will be DVD-R discs available that will hold around 20 GB of data, recorded into two layers on each side of the disc. At this time, these 20gb discs are not yet available. The most common DVD-R is a write-once 4.7gb disc that comes in two sub-types — “general purpose” and “authoring”. The general purpose discs are part of the industry’s copy-protection scheme, which employ CES scrambling to protect movies and music and game discs from being copied. These discs can only be burned by general purpose type DVD writers such as the Pi
