Internet glossary

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Database - A collection of data records. On web databases, records may consist of web pages, or graphics, or audio files, or newspaper files, or books, or movies, or press releases, or almost anything from very general to very specific areas of interest. Records may or may not be further broken into fields. Database records are usually indexed and come with a search interface to find records of interest.

DHCP (Dynamic Host Configuration Protocol) - A protocol by which a machine can obtain an IP number (and other network configuration information) from a server on the local network.

DHTML (Dynamic HyperText Markup Language) - Refers to web pages that use a combination of HTML, JavaScript, and CSS to create features such as letting the user drag items around on the web page, some simple kinds of animation, and many more.

Differentiated services - At present, all packets on the Internet are treated alike, regardless of their importance. If you want an important message to be delivered immediately or a streaming video signal to be distributed smoothly and without interruptions, there is no way to differentiate between immediate needs and routine transmissions which could be delayed for a long time without any problems. There are currently efforts under way to test and develop standards for differentiated services, where high priority data can be sent through or around clogged nodes ahead of low priority data. The high priority data transmission will cost more, of course. Internet glossary.

Digerati - The digital version of literati, it is a reference to a vague cloud of people seen to be knowledgeable, hip, or otherwise in-the-know in regardsto the digital revolution.

DNS (Domain Name System) - A system that translates Internet domain names into IP numbers. A "DNS Server" is a server that performs this kind of translation. Internet glossary.

Domain name - Domain name addresses, together with IP addresses, are the two forms of Internet addresses in common use. Domain name addresses all end with a correct top-level domain. The top-level domains may be any of these:

· com
· edu
· gov
· int
· mil
· net
· org
· a two-letter country code, such as us, uk, or mx.

The Internet Corporation for Assigned Names and Numbers (ICANN) announced a new series of top level domains available for registration. They are:

· biz
· pro
· museum
· aero
· name
· coop
· info

A complete domain address adds one or more terms to the left of the top-level domain, separated by dots. The top-level domain at the right is the most general; each term to the left is more specific.

Domain Name System (DNS) - Domain Name System. DNS servers are located at many strategic places on the nets to resolve the routing of e-mail and Internet connections. There are thirteen major, top-level DNS servers, which are updated daily, and these in turn feed the updated DNS information to smaller subordinate DNS servers, which hold more detailed information on their specific areas of coverage. No single DNS server has all the address information of the Internet, and successful routing may require routing through several levels of servers. Internet glossary.

DOS (See also DoS, which follows) - Acronym for Disk Operating System. Literally, the term refers that portion of an operating system that controls writing, storage, and retrieval of data from storage media, usually spinning disks of various types. In common usage, the term refers to MS DOS, the complete operating system developed by Microsoft for IBM-compatible personal computers in text (non-Windows) modes.

Download - Transferring data (usually a file) from another computer to the computer you are are using. The opposite of upload. Internet glossary.

DSL (Digital Subscriber Line) - A method for moving data over regular phone lines. A DSL circuit is much faster than a regular phone connection, and the wires coming into the subscriber's premises are the same (copper) wires used for regular phone service. A DSL circuit must be configured to connect two specific locations, similar to a leased line (howeverr a DSL circuit is not a leased line. A common configuration of DSL allows downloads at speeds of up to 1.544 megabits (not megabytes) per second, and uploads at speeds of 128 kilobits per second. This arrangement is called ADSL: Asymmetric Digital Subscriber Line. Another common configuration is symmetrical: 384 Kilobits per second in both directions. In theory ADSL allows download speeds of up to 9 megabits per second and upload speeds of up to 640 kilobits per second. DSL is now a popular alternative to Leased Lines and ISDN, being faster than ISDN and less costly than traditional Leased Lines. Internet glossary.

DTD - Acronym for Document Type Definition or optionally Document Type Declaration, used in SGML and XML markup languages to specify the set of rules or grammar processed in a particular language. HTML versions each have their own DTD, for example.