Google Geo Tools refer the Google apps which leverage geographic content. These include My Maps, Tour Builder, Streetview, and Earth. Many of these tools use KML files to communicate geolocations.
Keyhole Markup Language (KML) is a file format used to display geographic data in an Earth browser such as Google Earth. You can create KML files to pinpoint locations, add image overlays, and expose rich data in new ways. KML is an international standard maintained by the Open Geospatial Consortium, Inc.1 The simplest kind of KML documents are those that can be authored directly in the original Google Earth, in Tour Builder, and in My Maps meaning you do not need to edit or create any KML in a text editor. Placemarks, ground overlays, paths, and polygons can all be authored directly in these tools.2 Organizations such as National Geographic, UNESCO, and the Smithsonian have all used KML to display their rich sets of global data.3
When you create a map in Google My Maps or in Google Tour Builder, you have the option to export them as .KML files.
Additionally, in My Maps you can upload a .KML file to display as a layer over another map and in Tour Builder you can add a .KML as by URL.
How is this useful? For educators, it provides a way to collaborate or bring in professionally created content with student content. This is great for comparing data sources and drawing conclusions. Try visiting Google My Maps and using the “Explore” tab to find interesting maps, download them (as KMLs) and import them into your own map as layers. Have fun!
References
For more on this, check out Josh Williams awesome article “thanksgiving-fun-with-kml” on his blog: http://geteach.com/blog/2016/11/21/thanksgiving-fun-with-kml/