Essential KML vocabulary



A feature or element within a KML layer. Can be a container node or a geometry node. Nodes are shown as sublayers of the KML layer in the Contents pane.

Geometry Node

A node that has geometry associated with it. Geometry nodes can be placemarks, 3D models, polygons, lines, or multigeometry. A geometry node shows a symbol patch in the Contents pane.


A compressed or zipped KML file. KMZ files can be viewed and worked with in all the same ways as KML files.


A point feature or location on a point, line, or polygon feature that can be clicked to display pop-up information.


A line feature.


A polygon feature.

Ground Overlay

A raster or image that is typically georeferenced and draped on the earth's surface. Examples of ground overlays include aerial imagery or feature layers or maps converted to an image.

Screen Overlay

A map or screen graphic such as a logo, legend, or picture. Screen overlays are not part of the geographic display but are useful as information displays.

KML Regions

KML regions are typically used for large datasets. They are the equivalent of a tiling or image cache scheme in that they perform multiscale display in which data at each resolution is drawn only when it falls within the user's view and occupies a certain portion of the screen.

Network Links

A reference to an external file stored either locally or on a remote server. This could be an image used by an icon, ground overlay or screen overlay, 3D model, or another KML or KMZ file that gets automatically updated.


As KML is an XML-based format, its structure is based on various tags. For example, each point feature in a KML is inside a <Placemark> tag. The <Placemark> tag has subtags such as <name>, <Snippet>, and <description> which store information about the point, as well as a <Point> subtag that stores the x-, y-, and z-coordinates.

Custom Data

Allows the inclusion of attributes for features, which can be either typed or untyped. Typed data has defined data types such as string, integer, and float.

Snapshot View

A camera position defined for a node. When that node is zoomed to, the camera will both zoom and tilt to show the stored snapshot view.


COLLAborative Design Activity is an interchange file format that allows you to import 3D models into a KML.

KML vocabulary

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