Keyhole Markup Language
notation for expressing geographic annotation and visualization within Internet-based maps
Keyhole Markup Language is a file format for displaying data on maps.
In the same way that a Web browser displays web pages written with HTML, KML draws data on maps like Google Maps and virtual globes like Google Earth.
It is an international standard , maintained by the Open Geospatial Consortium .
Google, the previous maintainers of the specification, have information on writing KML on their website.