The extension .KML stands for Keyhole Markup language file. This type of file is used mostly to store, geographic information which is used for modeling the information in a xml based format. Internet based two dimensional maps and geographical interactive browsers use the data from the KML file to show the end users, detailed geographical visuals.

Orginally built for the famous Google earth, the KML was first known by the name, Keyhole Earth Viewer. The KML file type has now become the official standard at the Open Geospatial Consortium. Today, many other platform also use the KML format.