DVD recordable higher-capacity formats like Blu-ray and HD DVD. A double-layer DVD+RW specification was approved in March 2006 with a capacity of 8.5 GB. However, manufacturing support for these rewritable dual-layer discs did not materialize due to costs and expected competition from newer and higher-capacity formats like Blu-ray and HD DVD. DVD recordable DVD recordable and DVD rewritable are optical disc recording technologies. DVD optical disc formats that can be recorded by a DVD recorder, (written, “burned”), either write once or rewritable (write multiple times) format written by laser, as compared to DVD-ROM, which is technically mass-produced by pressing, primarily for the
Optical disc current third-generation discs and have the potential to hold more than one terabyte (1 TB) of data and meant for distributing Ultra HD video : There are numerous formats of optical direct to disk recording devices on the market, all of which are based on using a laser to change the reflectivity of the digital recording medium in order to duplicate the effects of the pits and lands created when a commercial optical disc is pressed. Formats such as CD-R and DVD-R are "Write once read many", while CD-RW and DVD-RW are rewritable, more like a magnetic recording hard disk