A globe is a model of a spheroid, usually of the Earth or another celestial body. They are a wonderful alternative to flat maps because they have none of the distortion problems that exist with traditional maps. There are many different types, ranging from the simple to the very complex and accurate.
The most common type of globe maps the Earth. Within this area, there are a number of different types, each with its own benefits and limitations. A standard Earth globe is made of a sphere covered in strips of paper which show either the political boundaries of the Earth, the topography of the Earth, or both. These papered spheres come in a range of quality, but all are essentially the same.
Another common type of Earth globe demonstrates the topography of the planet with exaggerated relief of the major physical characteristics. On this type, mountains are raised up beyond the surface of the sphere, while deep valleys or ocean canyons are depressed. Since the scale of elevation on the Earth is rather small in relation to the size of the Earth itself, this variety usually greatly exaggerates the size of mountains and valleys to make them readily visible.
More expensive models are often made of metal or another dense material, with political or topographical lines etched into the globe itself, rather than printed on paper strips. These range greatly in quality and value, from mass-produced globes designed for use in offices to collector's items which may be made of precious metals and even have gem inlays.
Recently, a number of globes have begun making use of small electromagnets to allow them to hover in the air and rotate on an axis between two magnets. These are relatively affordable, aesthetically pleasing and a good item for conversation.
In addition to globes which represent the Earth, some also exist which represent other celestial bodies. Most common are of either the moon or Mars, though globes of the other planets in our solar system also exist. Additionally, some specialty models depict fictional planets, such as Frank Herbert's Arrakis from the novel Dune. Yet another type, known as a star globe, depicts the stars in the sky as viewed from Earth. These globes are very useful for amateur astronomers and often also show the path of the sun, moon and other planets, as well as the major constellations and important celestial phenomena.
Lastly, there are virtual globes. Rather than existing in real space, these globes are mapped in a computer program. The resulting globe can then be explored in a virtual environment. Virtual globes offer a number of advantages over traditional globes, including the ability to integrate a huge amount of information. Many virtual globes make use of global imaging system (GIS) databases, as well as detailed country data, regional data and even real-time weather tracking.