Latitude/Longitude
The core of what makes Google Earth possible is the Latitude/Longitude system on Earth. Latitude and Longitude make it possible to reference a precise point on earth by simply showing a pair of numbers. For example, the Google headquarters in Mountain View, California is located at 37.422°N 122.084°W. Enter that into the Google Earth search box and you’ll fly directly there.
Google Earth allows you to display the current lat/lon in a variety of ways. The format shown above is known as “decimal degrees” and you’re given a few other choices such as Universal Transverse Mercator.
Google’s KML system simply uses decimal coordinates, as these don’t require a cardinal direction with each one. Continuing with the example of the Google headquarters, their coordinates are simply -122.084,37.422, which makes KML management much easier.
To see the latitude and longitude lines in Google Earth, simply pull down the [View] menu at the top of the screen and select “grid”, which will look something like this:
To learn more about the intricacies of latitude and longitude, I suggest you take a look at the latitude and longitude pages on Wikipedia.
Layers
Being able to fly around and find your house in Google Earth is pretty neat, but what makes the program so powerful are all of the layers that are built in. These layers go from the basics such as [Borders and Labels] and [Roads], to fun and useful layers such as [3D Buildings] and [Weather], to educational layers like [Greenpeace] and [WaterAid].In addition, the [Places] layer will highlight relevant locations in your area, and the [More] layer will let you fine-tune it further.
Frank wrote a great overview of layers a few years ago, which can help provide more depth into how they work. A few items from that article have changed (such as [Terrain] now being located in the [Tools] –> [Options] menu), but most of it is still very relevant.
If you want to experience the full power of Google Earth, take some time and explore the many amazing layers that are available for you to use.
About Mickey Mellen
Mickey has been using Google Earth since it was released in 2005, and has created a variety of geo-related sites including Google Earth Hacks. He runs a web design firm in Marietta, GA, where he lives with his wife and two kids.
Really helpful posts, hope they will be archived in a accessible spot, and Frank Taylor’s earlier post is great introduction to layers.
But I have never be able to find much official Google metadata, that is where their data is sourced from and a host of things like more detailed definitions and links to sources. Does anything official exist?
Also it is a while since there was serious discussion about the potentially confusing hierarchical structure of layers and the inadequate design of the layers panel. While some items have been moved around, nothing much has changed.
The title is Google Earth A to Z: Latitude/Longitude and Layers, but NO WHERE in this article do you actually say how to show them!!! Very frustrating!