ABSTRACT
The previous three chapters have deliberately avoided discussing elevation data and this has been for very good reason-it is so widely used as a primary source of data that it really requires a separate chapter to itself. Because it is a model of continuous variation, rather than discrete classified data, Elevation presents some particular challenges for both its storage and manipulation. In a sense, therefore, this chapter is best thought of as adding a specific example to Chapters 2, 3 and 4 and its remit is to examine how we can use GIS to store, capture and manipulate this particular class of data.
