What is a KML File ?

KML, Keyhole Markup Language, is an XML-based language used to display geospatial data in Google Earth. It formats georeferenced data for Google Earth to display.

What can I use a KML for ?

KML files can be used to depict data and information about a location.   Some of the industriest that use KML files are as follow.

Engineering Companies
Commerical and Real Estate Market
Insurance Companies
Government Agencies
Defense Industries
Homeland Security




What is a Geographic Coordinate System ?

Geographic Coordinate System (GCS) is a system used to reference a location in any part of the earth. The most common GCS system uses Longitude (the x value) and Latitude (the y value) to define the globe. These values create a grid pattern which divides the glove into 360 degrees. Each degree consists of 60 minutes and each minute consists of 60 seconds. s.
Example: 80 45 34.567 27 45 23.00234

What is a Projected Coordinate System? (Example: SPCS)

This is a mathematical representation that transforms the features of the glove and the curvature of the earth into a two dimensional surface (a flat surface, i.e. a map). The most common systems used in North America is the State Plane Coordinate System (SPCS - which uses feet) and the Universal Transverse Mercator (UTM - which uses meters).

UTM(Universal Transverse Mercator) projection ?

In 1947 the U.S. Army adopted the UTM projection, this system was designed to assign zones to large scale military maps of the entire world.   Using this projection the world can be subdivided into sixty zones, each zone consists of approximately six degrees wide of longitude.   There are also letter designations from north to south.

What is the Prime Meridian ?

By international convention, the Prime Meridian is the line of longitude which passes through Greenwich, London, UK. This marks the origin of the longitude line (longitude is define as 0). All longitude points to the west of this meridian line are negative and all points east are positive.

What is Latitude, what is Longitude ?

Latitude is a reference system used to determine the distance from the equator (latitude 0). It consist of 90 degrees beginning at 0 and ending at 90 degrees in a northern direction and 0 to 90 degrees in a southern direction. Longitude is a reference system used to determine the distance from the prime meridian (longitude 0). It consists of 180 degrees beginning at 0 and ending in 180 degrees in an eastern direction and 0 to 180 degrees in a western direction.

How do I convert DMS to DD ?

Converting DMS (degree minutes seconds) to DD (decimal degrees) is easy. You can use the following formula for the conversion:

DMS coordinates
Logitude =  80  45 34.234
Latitude =  27  32 12.567

DD LONGITUDE = 80 + (45/60) + (34.234/3600) => 80.75950944446
DD LATITUDE = 27 + (32/60) + (12.567/3600) => 27.53682416666