| A | B |
| daisy chaining | the act of stringing devices together in a series (such as SCSI). |
| database | an electronic list of information that can be sorted and/or searched. |
| data | information processed by a computer. |
| defragment | to concatenate fragments of data into contiguous blocks in memory or on a hard drive. |
| desktop | 1. the finder. 2. the shaded or colored backdrop of the screen. |
| desktop file | an invisible file in which the Finder stores a database of information about files and icons. |
| dialog box | an on-screen message box that appears when the Mac requires additional information before completing a command. |
| digitize | to convert linear, or analog, data into digital data which can be used by the computer. |
| disk | a spinning platter made of magnetic or optically etched material on which data can be stored. |
| disk drive | the machinery that writes the data from a disk and/or writes data to a disk. |
| disk window | the window that displays the contents or directory of a disk. |
| document | a file you create, as opposed to the application which created it. |
| DOS | acronym for Disk Operating System - used in IBM PCs. |
| DPI | acronym for Dots Per Inch - a gauge of visual clarity on the printed page or on the computer screen. |
| download | to transfer data from one computer to another. |
| drag | to move the mouse while its button is being depressed. |
| drag and drop | a feature on the Mac which allows one to drag the icon for a document on top of the icon for an application, thereby launching the application and opening the document. |
| driver | a file on a computer which tells it how to communicate with an add-on piece of equipment (like a printer). |
| Ethernet | a protocol for fast communication and file transfer across a network. |
| expansion slot | a connector inside the computer which allows one to plug in a printed circuit board that provides new or enhanced features. |