An Overview of the KL-ONE Knowledge Representation System.

KL‐ONE is a system for representing knowledge in Artificial Intelligence programs. It has been developed and refined over a long period and has been used in both basic research and implemented knowledge‐based systems in a number of places in the AI community. Here we present the kernel ideas of KL‐ONE, emphasizing its ability to form complex structured descriptions. In addition to detailing all of KL‐ONE's description‐forming structures, we discuss a bit of the philosophy underlying the system, highlight notions of taxonomy and classification that are central to it, and include an extended example of the use of KL‐ONE and its classifier in a recognition task.