This unique book is the key to computer contouring, exploring in detail the practice and principles using a personal computer. Contouring allows a three dimensional view in two dimensions and is a fundamental technique to represent spatial data. All aspects of this type of representation are covered including data preparation, selecting contour intervals, interpolation and griding, computing volumes and output and display. Formulated for both the novice and the experienced user, this book initially conducts the reader through a step by step explanation of PC software and its application to personal data, and then presents the rationale and concepts for contouring using the computer. Accompanying the book is a set of BASIC programs, in ASCII format, on an MS-DOS 360KB floppy disk. These programs implement eighteen interpolation methods, five gradient estimation techniques, and seven types of display, and are designed to be adapted or combined to suit a wide range of possible objectives concerning either the comparative study of contouring methodology or the practical production of contour displays.