Dedicated Line -- a telephone line that allows your computer to have a direct, permanent connection to the Internet. See T1 or T3.

Dial-up Account -- a basic type of Internet account that allows you to connect to an Internet service provider network with a modem. Many people have dial-up accounts to connect to the Internet from home, as opposed to an always-on connection like RoadRunner.

Digital -- a method of transporting analog waveforms by sampling them and translating them into a bit stream. The advantage of digital reproduction is that it can sound good over a long period of time. Records and tapes are analog; CDs are digital.

Domain -- all of the hardware and software that is under the control of one host computer. This term also describes the Internet's addressing scheme. Domains are represented by domain names such as e-NC.org or yahoo.com.

Domain Name -- the address that identifies an Internet site. Domain names consist of at least three parts. The first part is the http://www or just http://, which basically flags it as a web address. The second part is the name of the company, institution or organization. The third part, on the right, identifies the highest sub-domain. This can be a country, such as ca for Canada or fr for France, or the type of organization, such as com for commercial or edu for educational. For example, www.ncruralcenter.org is the domain name for the N.C. Rural Center, which is a non-profit organization or org.

Downlink -- communication link between a satellite and an earth station or ground-based receiver. Download -- to transfer a copy of a file from a remote computer to a user's computer.

Digital Subscriber Line (DSL) -- a method for moving data over regular phone lines. A DSL circuit is up to 50 times faster than a regular phone connection and uses the same (copper) wires used for regular phone service. A DSL circuit must be configured to connect two specific locations.