Google Earth is originally called as EarthViewer 3D and it is also a map, virtual globe, and geographical information program, which is created by Keyhole Inc. During 2004, Google acquired Keyhole Inc. this application maps all superimposition images directly from the satellite, GIS 3D (Geographic Information System), and Ariel photography. Google Earth includes 3 features and they are:
• a free version with limited functionalities
• With additional functionalities (discontinued)
• a version for commercial use (It approximately costs 400$ per year)
Google Earth is re-released during 2005, and it can be used in desktops / laptops that run Windows 2000 and later, Linux 2.6 and later, MAC OS 10.3.9 and later. recently, Google Earth is released as a plug-in in the browsers on may 28th 2008. on October 2008, mobile users can also access with this application on I-phone Operating System. it is also a free application, which can be downloaded from App Store. Android users can easily download this application on the Android market for free. while releasing the updated keyhole based client, Google has added imagery from Earth database for its web-mapping software, which is known as the Google Maps.
This application also displays images with various resolutions, where users can view houses and cities clearly. Resolution on lands covers at least 15 meters and larger part of lands covers 2D images in vertical photography. By using this application, users can view streets, sky, moon, mars, and oceans.
DEM (Digital Elevation Model) with NASA’s STRM (Shuttle Rader Topography Mission)
Google Earth also uses DEM data, which is collected by STRM. With this feature, the whole earth can be viewed in three-dimensions. since November 2006, users can also view several mountains, including the Mount Everest in three-dimensional views.