Map migrations

Like Extensible Markup Language, on which it is based, Geography Markup Language (GML) 2.0 is considered a meta-language, which means it consists of data that describes other information, such as how it is formatted and how it can be exchanged between applications.

According to officials at Galdos Systems Inc., the Open GIS Consortium Inc. member that leads the development of the language, GML has a number of advantages over the traditional method of presenting maps on the World Wide Web as GIF or JPEG files. Among them:

Simple tools. Only a Web browser is required; there's no need to use a particular application to view GML files. Faster panning and zooming. To zoom in on a GIF or JPEG map, a server must generate the request and send it to the browser. With GML, new views are produced instantly. Embedded links. GML enables a geographic feature to have a URL embedded in it. That allows a user to click on the feature and be taken to a related Web site.