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| CPU cache — A section of very fast memory residing between the CPU | ||
| and the computer’s main memory that temporarily stores data and | ||
| instructions the CPU will need to execute commands and programs. | ||
| See also cache, L1 cache, L2 cache. |
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| cursor — An | ||
| indicates the position where characters will appear when you enter | ||
| data. |
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D | default — The setting selected by a program when the user does not | ||
specify an alternative setting.
device — A component attached to the computer. Devices may be external (outside the computer’s case) or internal (inside the computer’s case). Printers, disk drives, and modems are examples of devices.
device driver — A program (called a “driver”) that permits a computer to communicate with a device.
dialog box — An
Direct Current (DC) — The type of power usually supplied by batteries. DC flows in one direction. Compare Alternating Current (AC).
Direct Memory Access (DMA) — A dedicated channel, bypassing the CPU, that enables direct data transfer between memory and a device.
directory — See folder.
disable — To turn a computer option off. See also enable.
disc — A round, flat piece of material, designed to be read from and written to by optical (laser) technology, and used in the production of optical discs, such as CDs and DVDs. Compare disk.
disk — A round, flat piece of material that can be magnetically influenced to hold information in digital form, and used in the production of magnetic disks, such as hard disks. Compare disc. See also hard disk.
disk drive — The device that reads and writes information and programs on external media or hard disk. It rotates the disk at high speed past one or more read/write heads.
