4) Explanatory Program
Explanatory Program is a set of procedures. Its mission is
responsible for the man-machine dialogue, which is
accepting user questions and answering user problems. For
system, the user can be roughly divided into two groups:
one is engineering and technical personnel who design and
maintain system; the other is users of system. An expert
system must be able to explain the given decision and
suggestions, otherwise, even if its decision or suggestions
are correct, it hardly be accepted by people. The main
function of explanation produce is explaining its own
reasoning results of system, and answering user questions.