What are intelligent tutoring systems?

All this is a substantial amount of work, even if authoring systems have become available to ease the task. This means that building an IT system is an option only in situations in which they, in spite of their relatively high development costs, still reduce the overall costs through reducing the need for human tutors. Such situations occur when large groups need to be tutored simultaneously or many replicated tutoring efforts are needed. Cases in point are technical training situations as exemplified by the thermostat case, training of military recruits, high school mathematics, etc.