  This article represents one of the contemporary trends in the application of
the latest methods of information and communication technology for medicine
through an expert system helps the doctor to diagnose some chest diseases which
is important because of the frequent spread of chest diseases nowadays in
addition to the overlap symptoms of these diseases, which is difficult to right
diagnose by doctors with several algorithms: Forward Chaining, Backward
Chaining, Neural Network(Back Propagation). However, this system cannot replace
the doctor function, but it can help the doctor to avoid wrong diagnosis and
treatments. It can also be developed in such a way to help the novice doctors.
