This image is a table showing examples of point, line, and area ordinal data. For point data, airports, symbols of oil well production, and populated places are shown by symbols that vary in size, colour or both. For line data, roads, drainage, and boundaries are shown by symbols that vary mainly in size, though they can vary in appearance and colour. For area data, the example shown are soil quality, cost of living, and industrial regions. Variations within these areal symbols can be shown by colours, by screens, or the use of both of these techniques.