Like many other fields of activity within the general area of `information technology', modern cartography is undergoing rapid changes in both form and character. This manual has been prepared under the auspices of the International Cartographic Association to provide a learning resource for students and an updating information source for technicians covering the use of new technology in cartography. use of new systems means that the traditional methodologies have to be augmented with new skills, and as a result the fundamental nature of the profession is changing. Volume 3 of `Basic Cartography for students and technicians' has been prepared to provide information on, and illustration of, the evolving technologies now providing cartographers with new methods for the visualisation and communication of spatial information to a growing, increasingly map-hungry, and ever more knowledgeable international audience.