KML files are used to describe geographic features and are associated with programs such as Google Earth. KML stands for Keyhole Markup Language which is used to designate coordinates and images related to geography. The file extension KML is created with XML (Extensible Markup Language), so the files are capable of being viewed on the Internet and can be used to pinpoint map coordinates.
KML files offer three-dimensional functionality and contain codes that provide a way to designate geographical points, such as latitude and longitude, lines, 3D models, placemarks, text and other components which are consistent with geography. Files that contain the KML extension are also versatile and allow you to implement camera angles, HTML, and textures in addition to being able to label specific areas of a geographical map. Due to file size, KML files are typically compressed into a KMZ format, which is a Zip format that can easily be transmitted over the Internet.
How to Open KML Files
KML files were originally developed by Keyhole Company before they were acquired by Google several years ago to be used with Google Maps and other Earth browser programs. Therefore, the primary way to open KML files is by using Google Earth.
Before you can open KML files for viewing, you must have a program such as Google Earth installed on your PC. If you do not have the program, you can download it by visiting the Google website. Once you have downloaded and installed the program, you can open KML files in Google Earth by copying the link to the KML or KMZ file and then simply pasting it into the search box for Google Maps. Or you can opt to paste the links into the Google search engine. When the search results appear, click on View on Google Maps to plot the contents of the KML or KMZ file using your browser.
Another method to open KML files is by using a compression program such as WinZip. Since KML files are compressed into a ZIP format, they will typically appear in your folder or email attachment with a KMZ extension. KMZ files contain all of the KML file content only it is compressed to save disk space and to expedite the file transmission process over the Internet.
You can open KML/KMZ files in a compression program by right clicking on the file and choosing Open With from the drop-down menu. Choose the compression program you use such as WinZip from the list or click on Browse to locate the program. You can also try double clicking on the KMZ file to see if it opens with the ZIP program you have installed by default.