Google Earth combines satellite maps, local yellow pages, and a vast database of statistics and information, and allows the user to zoom from outer space into street-level detail anywhere in the world, with impressive clarity and quality. If the immense volume of information is not staggering, the amount of customizable and user-friendly functionality in this application surely is. The best part is that google-earth comes free.
This BrightHub guide on google-earth features a host of useful and informative articles such as reviews on various features in the application, how to use different functions such as measuring area of a land, using google earth on various devices and operating systems, optimize performance, and so on. The guide also includes related information such as free geotagging tools, overview of various handheld devices and more!
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