An expert system in Artificial Intelligence is a system that has the ability to emulate the human ability of decision making easier. These systems are put into effect because of their abilities to solve complex problems easily by making of reasoning rather than the conventional procedural code which is used to program most of these AI systems. Expert systems have been around since the 1970s and are seeing a huge rise in popularity as they are very powerful when matched with the computing power of today. They are trained by keeping the actual subject matter experts in the picture to help build the knowledge base of the system while the inference engine is used to apply the rules it learned onto known facts to eventually deduce new facts. Inference engines come with an added advantage of being able to provide relevant debugging capabilities and explanation for the application of the rules.
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