Glossary - Index D
DDR: Double Data Rate - a type of Synchronous DRAM, or SDRAM. DDR SDRAM enables data transfers to occur on both edges of the clock cycle, thus doubling the memory throughput of the chip.
DDR RAM: An extention of SDRAM technology, DDR effectively doubles the bandwidth available by sending data on the falling edge of the clock cycle as well as on the rising edge.
Desktop: No, not the thing your keyboard and mouse are sitting on, but rather the main screen on your monitor where you find your icons, background wallpaper and maybe your screensaver.
DHCP: Dynamic Host Configuration Protocol - Method of assigning temporary IP addresses to computers to ensure network security.
Digi board: Hardware to build a ras server.
Dimm: DIMM RAM is characterized by its 168 pins.
DIMM Slots: DIMM memory fits into special 168 pin slots which are located on the motherboard, usually adjacent from the processor.
DOCSIS: Data Over Cable Service Interface Specification - A standard for transferring internet data over cable lines.
Dot Pitch: Used to describe the horizontal size of pixels on CRT and LCD displays. The smaller the dot pitch (for example 0.25 mm) the better the resolution of the display.
Double Click: 2 clicks of the mouse at the same time. If the program detects a double click it often will open the selected application.
DSL: Digital Subscriber Line - High-speed internet connection offered by telephone companies over existing phone lines.
DVD: Digital Versatile Disc - Introduced in 1996, the optical discs share the same overall dimensions of a CD, but have significantly higher capacities - holding from 4 to 28 times as much data.
DVD Video: Popular format for high quality MPEG2 video and digital surround sound. Enables multi-language, multi-subtitling and other advanced user features.
DVD+RW: DVD ReWritable - It is the only rewritable format that provides full, non-cartridge, compatibility with existing DVD-Video players and DVD-ROM drives for both real-time video recording and random data recording across PC and entertainment applications.
DVD-Audio: This audio-only storage format similar to CD-Audio, however offers 16, 20 and 24-bit samples at a variety of sampling rates from 44.1 to 192KHz, compared to 16 bits and 44.1KHz for CDs. DVD-Audio discs can also contain music videos, graphics and other information.
DVD-RAM: DVD Random Access Memory - A rewritable DVD disc endorsed by Panasonic, Hitachi and Toshiba. It is a cartridge-based, and more recently, bare disc technology for data recording and playback. DVD-RAM bare discs are fragile and do not guarantee data integrity. The first DVD-RAM drives had a capacity of 2.6GB (single sided) or 5.2GB (double sided). DVD-RAM Version 2 discs have double-sided 9.4GB discs. DVD-RAM drives typically read DVD-Video, DVD-ROM and CD media. The current installed base of DVD-ROM drives and DVD-Video players cannot read DVD-RAM media.
DVD-ROM: Read Only Memory - This read-only DVD disc is used for storing data and interactive sequences as well as audio and video. DVD-ROMs run in DVD-ROM or DVD-RAM drives, not DVD-Video players connected to TVs and home theaters. However, most DVD-ROM drives will play DVD-Video movies.
DVD-RW: DVD ReWritable - A rewritable DVD format that is similar to DVD+RW, but its capability to work as a random access device is not as good as +RW. It has a read-write capacity of 4.7 GB.