Keyhole Markup Language (KML) is an XML-based format that describes geographic entities. Developed and popularized for use with Google Earth, the KML specification is now maintained by the Open Geospatial Consortium (OGC). KML can be used to draw features such as points, lines, and polygons on maps or even designate text, images, and media that appear when the user clicks a feature. Developers can use KML files in the
.kmz formats as the source for layers in ArcGIS applications. While KML was initially created to view features in three-dimensional Earth browsers, it is now supported in several two-dimensional web browser clients, such as Map Viewer, with certain limitations.