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topology — English
Describing the location of a place or a phenomenon without considering distance, orientation or straightness. It is a very old technique as people have always drawn topological maps to describe where certain farms, buildings, rivers, bridges or sacred sites are located or even where a great treasure is buried! A general leading an army in a war, will often draw a sketch map with a stick in the sand to explain the attack strategy to his men, and if you quickly drew a sketch map to guide a friend to your house, the general and you have both drawn topological maps. Topology was recognised as a formal scientific technique in the 1700s and there are certain rules, basic ingredients, terms of transformation and even mathematical relationships involved in the methodology of topology. A topological map is not drawn to scale and neither the shapes nor directions nor the distances are accurate, but one will be able to find the place you are looking for. Certain easily seen or generally known landmarks feature prominently on a topological map, although they might not even be indicated in their correct locations, and the distances between them would not be indicated accurately. The military and the tourism industry use topological maps all the time. From a tourist information booth one can easily acquire a flyer or brochure about the Cradle of Humankind world heritage site, and it will usually contain a topological map which would direct you to the site and to the different places of interest within the site. In GIS, topology is the spatial relationship between adjacent, contingent or connected features. The relationships between features are recorded in a set of related tables. Topology ensures that the relative locations of features stay the same if the data layers are distorted, for example through the application of a projection type.
