Keyhole Markup Language (KML)
| Item | Description |
|---|---|
| Current Status | Open Standard by Open Geospatial Consortium; broad use |
| Version Number | 2.3 |
| Key Contacts | KML 2.3 Standards Working Group http://www.opengeospatial.org/projects/groups/kmlswg |
| Implementing Agencies | Various – KML support is included in Google products as well as several open source and commercial products. Open source libraries have also been released to support desktop software integration. |
| Documentation | http://www.opengeospatial.org/standards/kml/ |
| Founding/Sponsoring Organizations | Created by Keyhole, Inc, which was acquired by Google in 2004. Later submitted to Open Geospatial Consortium, which now oversees the standard. |
Background
Keyhole Markup Language (KML) is an XML notation for expressing geographic annotation and visualization. This notation can be viewed within web-based and two-dimensional maps and three-dimensional Earth browsers. KML was originally named Keyhole Earthviewer and developed for use with Google Earth software. It was created by Keyhole, Inc, which was acquired by Google in 2004. In 2008, the Open Geospatial Consortium adopted KML as an international standard. While Google Earth was the first program able to view and edit KML files, it was later supported in several mapping software tools.
Analysis
KML is widely used for use of sharing 2D and 3D geospatial data in xml format on the web. It is well suited for sharing styled geographic data but attribute data (tabular information conventionally attached to a geometry feature) is not well supported. Metadata is also not supported. The use of KML as an interchange standard is declining. Further, a new version of the standard that would be harmonized with other OGC standards was never released and no new versions have been released since it was submitted by the OGC.
Additional Resources
- KML support in GDAL/OGR - http://www.gdal.org/drv_libkml.html
- Google LibKML - https://github.com/google/libkml
- LibKML resources - https://code.google.com/p/libkml/w/list