Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online.A virtual globe is a 3D software model or representation of the Earth or another world. A virtual globe provides the user with the ability to freely move around in the virtual environment by changing the viewing angle and position. Compared to a conventional globe, virtual globes have the additional capability of representing many different views on the surface of the Earth. These views may be of geographical features, man-made features such as roads and buildings, or abstract representations of demographic quantities such as population. In 1998, Microsoft released a popular offline virtual globe in the form of Encarta Virtual Globe 98. The first widely publicized online virtual globes were NASA World Wind and Google Earth.