A considerable amount of computer software, often called courseware, has been developed during the last decade, to help provide a learning environment in which students can explore the material which is presented to them. This has included a symbiotic approach in which the text and software are more integrated. In addition, the rapidly increasing power of personal computers has meant that dynamic graphical capabilities can now be exploited. A natural extension is to add new features to produce a more comprehensive learning environment, features such as sound, animation and video. The era of multimedia in which vast resources are made available either on a CD or network has arrived.