Languages for Knowledge Representation

One of the examples is KRL, developed by Bobrow and Winograd from Stanford University [10]. KRL supports knowledge representation in different declarative forms based on conceptual objects that form a network. KRL is basically an interpreter that allows LISP expressions to be formulated in a more expressive fashion. It includes an inference engine with a backward-chaining mechanism. 

KL-ONE is a frame-like family of knowledge representation approaches in the tradition of semantic networks [11], It was developed to overcome some of the drawbacks of semantic networks and represents conceptual information in a structured network for inheritance. The frames — in the KL-ONE approach called concepts — are arranged in a class-like hierarchy that includes the relations between frames. Frames are typically inherited from super classes. 

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