data access time The time needed for a computer to locate and transfer data to primary memory.
data bus A bus that connects the CPU and memory, providing a pathway to the computer's peripherals.
data definition language (DDL) One of four parts of a database management system (DBMS) used to define the structure of the database.
data dependence The dependence of data on the application in which the data is stored; data dependence occurs when data files from different applications are incompatible and cannot be linked.
data entry personnel Individuals who key in data from source documents.
data file A file, created by a program, in which data is stored.
data integrity The validity and consistency of the data in all applications.
data manipulation language (DML) One of four parts of a database management system (DBMS); DML includes all commands that enable a user to manipulate and use the database.
Data Processing Management Association (DPMA) The premier organization for CIS personnel and managers.
data redundancy The repetition of the same data in two or more data records.
data security Features included in database packages to protect data from individuals not authorized to use it.
data storage hierarchy The organization of data from smallest (bit) to largest (database).
data transfer rate The rate at which two modems can exchange data.
data transfer time The time required to transfer data to primary memory.
database A collection of related information electronically stored and organized in a useful manner that acts as a base for retrieving information.
database administrator The person who oversees a database. The database administrator ensures that data is entered correctly, develops procedures for the analysis of data, and ensures database security.
database file A file containing data that has been stored in the proprietary file format of a database program.
database management system (DBMS) A program that organizes data in a database, providing information storage, organization, and retrieval capacities.
debit card A credit card used to transfer funds electronically from a bank account to a business account.
debug The process of finding and fixing bugs (errors) in a computer program.
debugging See debug.
decision A programming construct in which one set of instructions is executed if a condition is true, and a different set of instructions is executed if the condition is false; also called a condition.
decision support system (DSS) A tool to help management analyze data to make decisions on semistructured problems.
dedicated line A special conditioned telephone line that directly and permanently connects two computers.
default value A common formatting value that a program uses when some other formatting value isn't specified.
defragmentation program A utility program that reads all files on a disk and rewrites some of them so that all parts of each file are contiguous.
demodulation In telecommunications, the process of receiving and transforming an analog signal into its digital equivalent so that a computer can use the information.
deskilling The replacement of jobs by machines through automation and advanced technology.
desktop computer A nonportable microcomputer that fits on top of a desk.
desktop publishing (DTP) The combination of text, graphics, and advanced formatting to create inexpensively a visually appealing document.
desktop videoconferencing Conferencing by computer; software enables conferees to see each other and discuss a document viewable on all their screens. Desktop videoconferencing software can be run alone, permitting users to hear each other, or with a camera mounted on top of the monitor to transmit a picture.
dialup access The use of a personal computer and a modem to connect with a computer having direct Internet access.
dialup IP A form of direct access in which a modem and a telephone line are used.
difference engine A steam-driven calculating machine created by Charles Babbage in the nineteenth century and capable of solving equations and printing tables. Technology at the time had not advanced enough to produce this invention.
digital A number representation for something in the real world, such as temperature or time, so that counting can be performed precisely.
digital modem A device that helps linked computers synchronize data transmission and provide error correction.
digital video disc (DVD) A disk that can hold seven to twelve times the amount of data on a CD-ROM, transfer data faster than the fastest CD-ROM today, and record data at your computer.
digitizing The conversion process by which scanners convert images into numeric digits before storing them in the computer; the process of converting data into digital form.
digitizing tablet In computer-aided graphics, a peripheral device used with a pointing device to convert graphics into data that a computer can process.
direct-access file A file in which records are stored according to a position in the file, enabling the computer to read specific records from the file; also called a random-access file.
direct conversion The changing of existing data files to the format of another application.
direct Internet access The capability of a computer to send and receive Internet data packages without an intermediary.
directory An area on a disk where you can store files. A directory listing shows the directory contents by file name. The files in a directory can be programs or data documents.
disaster recovery disk The essential operating system files along with the files necessary to restore the system from backup files in the event of a computer failure.
disaster recovery plan An organization's written plan, with detailed instructions, specifying an alternative computing facility to use for emergency processing until a destroyed computer can be replaced.
disk drive A mechanism designed to store and retrieve information on a floppy disk.
display font An eye-catching font, often used for headings and captions, that is larger than the body font of the document.
distance learning A technique that uses computers and telecommunications to take the classroom to the student at a remote location.
docking station A cabinet containing disk drives, video circuits, and specially designed receptacles for housing a portable computer so that it can use peripheral devices.
documentation The instructions, tutorials, and reference information that provide the information a user needs in order to use a computer system or application.
Dance on Microcomputer (DOM notation) A computer program that produces an animated figure for performing dance routines.
domain name The name that identifies the computer system on which the user has an account.
dot-matrix printer An impact printer that forms text and graphic images by hammering the ends of pins against a ribbon in a pattern (matrix) of dots.
dot pitch The distance between pixels.
double-density disk A disk capable of storing twice as much data as a single-density disk.
double-speed drive A drive providing the minimum level of retrieval speed for multimedia applications.
download To transfer a file from a remote computer to your own computer.
downwardly compatible A capability of hardware or software that runs without modification when using earlier computer components or files created with earlier software versions.
DRAM See dynamic RAM.
drawing program A program that uses object-oriented graphics to produce line art.
dumb terminal A terminal that interacts with the remote computer but cannot process any information.
dynamic RAM (DRAM) A random-access memory chip that is slower than VRAM and is often used on video cards to store video information.