It was developed at the University of Salford in a 18-month project funded by the Alvey Programme.
All modules operate by asking the user a sequence of questions.
The knowledge base contained links that determine the dependencies among the pieces of information held, so that the answers given are propagated 'intelligently' throughout the knowledge base and may affect which questions are asked later on, or in which order. Now' point, at which explanation reports can be obtained, information can be over-ridden, and the information can be archived in the project database for later use. Not only may the answers to the question sequence be overridden but also upwards of a hundred assumptions that the module makes. In practice, the question answers would be changed to perform what-iffing, while the assumptions would be overridden to take account of special or local circumstances. The user interface is relatively simple, comprising 'windows' composed of character graphics.