DVD-ROM, or Digital Versatile Disc Read Only Memory, refers to the original DVD format of a high capacity optical storage disc that can only be read and not written. Data is already pre-recorded on the disc by the manufacturer when it reaches the consumer. Movie rentals, retail movies, and large software applications are all examples of DVD-ROMs in the global market.
DVD-ROMs are engineered for all storage capacities: single-sided single layer, single-sided double layer, double-sided single layer, and double-sided double layer.
Additional layers and sides equate to more recorded data than a CD due to its higher density in binary data. The optics of a drive will look for an ADIP, or “Address in Pre-groove” signal to guide the laser to read the correct layer. DVD-ROM’s data layer position in the middle of the disc enables double-sided storage.
DVD-ROM has its advantages over some of its optical storage predecessors. Consumers will experience improved color and picture quality. These discs are also capable of six and seven-digit surround sound channels. They contain track skipping options, parental controls, and 32 choices in closed captioning. DVD-ROM employs the MPEG-2 format for audio and video compression—a widely accepted standard for television’s NTSC and HDTV options.
A drive’s laser reads a DVD-ROM from the center and follows the spiral tracks outward. A DVD-ROM will be compatible with DVD players as well as drives on PCs and Macs.