An expert system is a computer program that uses artificial intelligence (AI) technologies to simulate the judgment and behavior of a human or an organization that has expertise and experience in a particular field. Expert systems are usually intended to complement, not replace, human experts.
In artificial intelligence, an expert system is a computer system emulating the decision-making ability of a human expert. Expert systems are designed to solve complex problems by reasoning through bodies of knowledge, represented mainly as if–then rules rather than through conventional procedural code.
Backward chaining – an inference technique which continuously break a goal into smaller sub-goals which are easier to prove via IF THEN rules.
Dealing with uncertainties – the system has the capability to handle and reason with conditions that are uncertain and data which are not precisely known.
Expert systems that are in use include the following examples: CaDet (Cancer Decision Support Tool) is used to identify cancer in its earliest stages. DENDRAL helps chemists identify unknown organic molecules. DXplain is a clinical support system that diagnoses various diseases.
