Google Earth is a virtual globe, map and geographic information program that was originally called Earth Viewer, and was created by Keyhole, Inc, a company acquired by Google in 2004. It maps the Earth by the superimposition of images obtained from satellite imagery, aerial photography and GIS 3D globe. It is available under three different licenses: Google Earth, a free version with limited functionality; Google Earth Plus (discontinued), which included additional features; and Google Earth Pro ($495 per year), which is intended for commercial use.
The product, re-released as Google Earth in 2005, is currently available for use on personal computers running Windows 2000 and above, Mac OS X 10.3.9 and above, Linux Kernel: 2.4 or later (released on June 12, 2006), and FreeBSD. Google Earth is also available as a browser plugin (released on June 2, 2008) for Firefox 3, Safari 3, IE6 and IE7. It was also made available on the iPhone OS on October 27, 2008, as a free download from the App Store. In addition to releasing an updated Keyhole based client, Google also added the imagery from the Earth database to their web based mapping software. The release of Google Earth in June 2005 to the public caused a more than tenfold increase in media coverage on virtual globes between 2005 and 2006, driving public interest in geospatial technologies and applications.