DDR (Double Data Rate):
DDR is a new generation of RAM which doubles on-board data transfer. DDR RAM allows texture to be loaded and mapped twice as fast in games.

Depth shading:
Also known as distance shading, fog shading or depth cueing. This is to prevent a processor from having to render objects in a 3D environment out to infinity, which would cause monumental slowdown. After a certain predetermined distance, an object is considered to be out of range and is no longer rendered. To prevent objects suddenly popping up, they are shaded to appear as though they are coming out of a fog.

Digital:
A way of representing information (such as the height of a sound wave or the color of a pixel) that uses a number of discrete values.

Direct3D:
This is Microsoft's DirectX programming API (Application Programming Interface) that comes with DirectDraw, DirectSound, DirectPlay, Direct3D and DirectInput). Direct3D includes support of and control over low level transformations, rasterization and lighting. The latest version of DirectX 8.0 contains Direct3D. There are games made with Direct3D's APIs and these are 100% compatible with 3D Prophet graphics boards.

DirectX:
A series of utilities created by Microsoft, intended to optimize 2D, 3D and sound features.

Dithering:
A process which enables the system to create the illusion of displaying more colors than it can actually generate. Color dithering is achieved by placing dots of different colors next to each other in a variety of patterns. When looked at from a distance, the combined effect is a new color, since dithering takes advantage of the human eye's propensity to average the colors in a small area. For instance, placing blue and yellow dots next to each other in a checkered pattern will create an impression of the color green.

DRAM (Dynamic Random Access Memory):
Conventional random access memory (RAM) used on lower- and mid-range graphics boards. Random access memory is required by the system to store data and programs prior to processing. The amount and operating speed of this memory have a direct incidence on a PC's performance. Indeed, some applications, such as technical or scientific calculations or CAD (Computer-Assisted Design), will require a certain minimum amount of memory to operate correctly, offering decent performance. In addition, the quicker the memory access time, the lower the processor queuing time.

Draw in:
This can occur in 3D games, where whole objects suddenly pop-up into view. It occurs either because of bad programming of clipping areas, or a lack of processor power, which prevents the system from rendering objects until they are too close.

Drop out:
When too many polygons are being displayed on-screen to allow display update at a constant rate. Some of the polygons may "drop out" and disappear.

DVD (Digital Versatile Disc):
A new standard for digital optical discs, DVD is the next step. It promises up to 10 times the storage capacity of current CD-ROMs.

DVI (Digital Visual Interface):
The DVI standard for digital display has been established by the Digital Display Working Group (http://www.ddwg.org/), an open industry group including Intel, Compaq, Fujitsu, Hewlett Packard, IBM, NEC and Silicon Image. DVI replaces former standards of digital display to provide a single standard for digital display. DVI is compatible with older standard monitors, and requires only a cable adapter to support them. The benefits of DVI CRTs are: