D3D Score: The score that the Windows Experience Index gives to your computer's ability to replicate 3D images.

DAT: Digital audiotape; A type of computer backup drive that copies data to a tape.

DDR: Double data rate; A computer DIMM memory module that’s still in general use.

DDR2: Memory modules that double the data transfer rate between your RAM and your motherboard.

default programs option: A Windows option that allows you to determine which program you want to run a certain task or open a certain file type.

defrag; defragment: The process that your computer uses to rearrange the pieces of files and applications on your hard drive so that they are positioned next to each other on the drive, improving performance speed.

desktop: A type of computer made up of a PC console, monitor, mouse, keyboard, and any additional attachments. A desktop PC isn’t easily portable.

desktop theme: A collection of settings that control the appearance and behavior of the various appearance settings in Windows.

details view: One of the viewing options in Windows Explorer that you can use to obtain detailed information about each file.

Device Manager: A Windows tool that shows you the status of all the hardware elements on your PC.

dialup: A kind of computer Internet connection that uses existing phone lines.

digital: A means of storing, transmitting, manipulating, or reproducing data, images and sounds by using groups of electronic bits represented by 1 and 0.

Digital ID: Electronic certificates that you can use to verify the identity of the person with whom you’re communicating.

DIMM: Dual Inline Memory Module; A standard type of computer memory module.

DirectX: A driver used by games, graphics, and audio programs in Windows.

disk drive: A component of a computer that reads information from and writes information to a certain kind of disk.

display: The information that appears on your computer screen.

DNS Server: A computer that translates addresses you can understand, such as www.dummies.com, into addresses that the Internet can understand, such as

drive cage: A contraption used to hold a PC’s internal disk drives, an optical (DVD) drive, and a hard drive.

driver: A special type of program that allows specific computer hardware to work.

DSL: Digital Subscriber Line; a type of Internet connection that takes advantage of unused frequencies in existing phone lines.

dual-core: A CPU made up of two independent processors combined onto a single integrated circuit.

DV: Digital video; used to describe camcorders that record video digitally.

DVD: Digital video disc; a removable computer storage medium that has a larger capacity than a CD.

DVD drive: A disk drive in or attached to your computer that can read information from DVDs and CDs.

DVI: Digital video interface: The standard connection method for certain types of video display, such as LCD monitors.

DVI-to-VGA adapter: An adapter that allows you to connect an older monitor to a newer computer or vice versa.

dye-sublimation: A type of printer that transfers heated solid dye from a ribbon to specially coated paper, producing continuous tones, like those in a photo produced from a negative.