Relationships between places defined by their proximities (e.g., relative location, Euclidean and non-Euclidean metrics, distances in rasters, buffers, multidimensional scaling, weight matrices, and social distances. 'Distance between points is easily calculated using formulas for straight-line distance on the plane or on the curved surface of the Earth, and with a little more effort it is possible to determine the actual distance that would be travelled through the road or street network, and even to predict the time that it would take to make