Point representation

Points are defined as single coordinate pairs (x, y) in 2D space, or coordinate triplets (x, y, z) in 3D space. Points are used to represent objects that are best described as shapeless, size-less, zero-dimensional features. Whether this is the case really depends on the purposes of the application and also on the spatial extent of the objects compared to the scale used in the application. For a tourist map of a city, a park would not usually be considered a point feature, but perhaps a museum would, and certainly a public phone booth might be represented as a point. In addition to the georeference, administrative or thematic data are usually stored for each point object that can capture relevant information about it. For phone-booth objects, for example, this may include the telephone company owning the booth, its phone number and the date it was last serviced.