kml and gml

[ned...@gmail.com]

Could you tell me what are the differences and similars between KML
and GML and between KML and XML?

Thank You

[Jonathan van Tuijl]

> Could you tell me what are the differences and similars between KML
> and GML and between KML and XML?

I don't have experience with GML. XML is just the markup language KML
is based on:
http://en.wikipedia.org/wiki/XML

Jonathan

[Standards Guy]

On Aug 30, 4:01 pm, Jonathan van Tuijl wrote:
> > Could you tell me what are the differences and similars between KML

> > andGMLand between KML and XML?
>
> I don't have experience withGML. XML is just the markup language KML

> is based on:http://en.wikipedia.org/wiki/XML
>
> Jonathan

You can get more information about GML from http://www.ogcnetwork.net/gml
. In a nut shell, the Geography Markup Language (GML) is an XML
encoding for the transport and storage of geographic information,
including both the geometry and properties of geographic features. The
GML geometry model is based on ISO 19107 (Features). GML supports the
ability to encode a wide range of geospatial content, including
topology, simple and complex geometry, metadata, temporal, and
styling. KML is more focused on solving the visualization/styling of
simple geographic features in earth browsers. From the preamble to the
OGC KML Best Practices document:

What information sharing space is KML targeted at? KML is an XML
language focused on geographic visualization, including annotation of
maps and images. Geographic visualization includes not only the
presentation of graphical data on the globe, but also the control of
the user's navigation in the sense of where to go and where to look.
>From this perspective, KML is complementary to most of the existing
OGC specifications including key standards such as GML (Geography
Markup Language), WFS (Web Feature Service) and WMS (Web Map Service).
Currently, KML (v2.1) utilizes certain geometry elements derived from
GML (version 2.1.2). These elements include point, line-string, linear-
ring, and polygon.

While there is some overlap between the functionality of GML and KML,
they are designed to solve different geospatial interoperability/data
sharing problems. The OGC membership will soon be approving KML 2.2 as
an OGC Best Practices and work has begun on harmonization of certain
elements of KML with other OGC standards, such as coordinate reference
systems and GML/ISO 19107.

Carl