Resources

Web Glossary


Demographics
Demographics are the DNA of marketing: age, gender, income, profession, marital status, location, and so on. Advertisers rely on demographics to help decide which sites are most likely to help them reach their specific audience. Knowing your audience demographic not only helps you sell ads, it also lets you know who your users are and what they want.

DHCP (Dynamic Host Configuration Protocol)
An addressing protocol for TCP/IP networks. IP addresses are leased to individual computers on the network from a DHCP server. DHCP allows users to move to different locations on a network without having to bother a network administrator to manually assign a new IP address. DHCP is useful where several computers share a single high-speed Internet connection.

DNS (Domain Name Server)
DNS matches the URL you enter with the IP address of the item you're looking for. All web sites are located at an IP address. URL's are just easier to remember names that stand-in for the IP address. Domain Name Servers maintain a list of domains and their corresponding IP addresses. When a new domain is registered, it can sometimes take several hours (or even days) for DNS to "propogate". That is, for Domain Name Servers around the world to record a match for a given domain and an IP address. Whether or not a URL goes where it is supposed to is a result of whether your ISP's DNS is up-to-date.

Domain
Hierarchical scheme for indicating logical and sometimes geographical venue of a web-page from the network. In the US, common domains are .edu (education), .gov (government agency), .net (network related), .com (commercial), .org (nonprofit and research organizations). Outside the US, domains indicate country: ca (Canada), uk (United Kingdom), au (Australia), jp (Japan), fr (France), etc. Neither of these lists is complete.

Download
To copy something found on the Web (located on its server) to your hard drive or removable media.

DPI (Dots Per Inch)
The measurement of the resolution of images on a screen or printed page. Most laser printers use 600 DPI (600 across and 600 down). The more dots, the better the resolution. Image purists insist on a difference between dots per inch for print and pixels per inch on the screen, since monitors of different sizes have different size pixels or more pixels per inch in the display.

DSL (Digital Subscriber Line)
A method for moving data at high speed over regular phone lines over the same (copper) wires used for regular phone service.

Data Model
A planning document that describes the framework for a database to be developed. A good data model includes field names, sizes in terms of number of characters, the type of field each is required to be, and how fields and tables interrelate.

DHTML (Dynamic HTML)
DHTML adds a number of characteristics to normal HTML, allowing for more multimedia and interactive possibilities, such as layering, motion, and the use of a timeline. There can be some problems in the interpretation of DHTML code from browser to browser and platform to platform.