The user interface is a crucial, but often overlooked, part of the computer and software package. It is often the last thing designed. Short term memory aids and session pacing are two of the most important areas in which the machine can assist the user. Inclusion of a screen pointing device brings the computer closer to communicating on human terms. Basing the interface on a common metaphor, e.g. a desk top, can make it easy to learn and use. In this thesis three facets of the interface are examined. Communication from the machine, to the machine, and the dialog between user and machine. The Amiable interface designed for the UNIX operating system is described. Amiable is implemented on a SUN model 150 Workstation in the Naval Postgraduate School Computer Science Laboratory. Interface design is a hard problem, much remains to be done.
