1. Introduction
One reason that ITS is such a large and varied field is
that ‘‘intelligent tutoring system” is a broad term, encompassing
any computer program that contains some intelligence
and can be used in learning. ITS is an outgrowth
of the earlier computer-aided instruction or CAI model,
which usually refers to a frame-based system with hardcoded
links, i.e. hypertext with an instructional purpose.
The traditional ITS model contains four components:
the domain model, the student model, the teaching model,
and a learning environment or user interface. ITS projects
can vary tremendously according to the relative level of
intelligence of the components. For example, a project
focusing on intelligence in the domain model may generate
solutions to complex and novel problems so that students
can always have new problems to practice on, but it migh