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In computing, Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can be applied to any kind of XML document ( ).


In computer networking, the term client-side refers to operations that are performed by the client in a client-server relationship. Typically, a client is a software program, such as a web browser, that runs on a user's local computer or workstation and connects to a server as necessary. Operations may be performed client-side because they require access to information or functionality that is available on the client but not on the server, because the user needs to observe them or provide input, or because the server lacks the processing power to perform the operations in a timely manner for all of the clients it serves. Additionally, if the client can perform operations without sending data over the network, they may take less time, use less bandwidth, and incur a lesser security risk ( ).


Context-sensitive refers to an application software feature that changes depending on what the user is doing within the software. For example, context-sensitive help provides documentation for the particular feature that the user is in the process of using (


Coordinates indicate where a particular point is on a map in relation to the surface of the earth. They are expressed by the longitudinal extent (indicated as either north or south of the Equator) in relation to the latitudinal extent (indicated as either east or west of the Greenwich Meridian). Coordinates may be expressed in various formats including degrees, minute and seconds, decimal degrees and degrees and decimal minutes.


A GIS coverage stores features making up a map as primary features e.g. nodes, polygons, arcs and label points, and secondary features e.g. map extent, links, tics and annotations. A feature attribute table is associated with the coverage and describes and stores attributes of the map features. A coverage usually represents a single theme, or layer, such as soils, roads, or land use. (


A database is a collection of interrelated data, managed and stored as a unit. A GIS database includes data about the spatial location and shape of geographic features recorded as points, lines, and polygons as well as their attributes (


A datum is a set of parameters and control points used to accurately define the three dimensional shape of the Earth. The corresponding datum is the basis for a planar coordinate system (

DBF (File format):

DBF is the extension for files in the dBASE format, the first widely used database management system or DBMS for microcomputers. Although dBASE never successfully managed the transition to Microsoft Windows its underlying file format, the dbf file, is widely used in many other applications needing a simple format to store structured data (

Decimal Degrees:

Decimal degrees are a geographic coordinate system used for mapping the Earth's surface using degrees of latitude and longitude where each degree is divided into decimal fractions rather than minutes and seconds.

Degrees, Minutes, Seconds:

Degrees, minutes and seconds are a geographic coordinate system used for mapping the Earth's surface. The globe is divided into 180 degrees of latitude (90 on each side of the Equator); and 360 degrees of longitude (starting at the Greenwich Meridian and counting up to 180 degrees to both the East and West). Each degree is divided into 60 minutes and each minute into sixty seconds.


The Domain Name System (DNS) is an information system that stores the information associated with domain names in a distributed database on networks, such as the Internet. The domain name system associates many types of information with domain names, but most importantly, it provides the IP address associated with the domain name. It also lists mail exchange servers accepting e-mail for each domain. The DNS makes it possible to attach hard-to-remember IP addresses (such as to easy-to-remember domain names (such as ""). Humans take advantage of this when they recite URLs and e-mail addresses (

Drill down:

In information technology drill down refers to moving from summary information to detailed data by focusing in on something. In a GIS a drill down identify generates information from the attribute tables not only for the geographical point on the layer which is active but also for all other layers at that point which may be hidden (

Dynamically generated:

Dynamically generated in computing refers to an output that is made at runtime by the invocation of scripts or programs that are ultimately requested by a user, or the programmed/scheduled events supported by the Web server (