Planner (often seen in publications as "PLANNER") is a programming language designed by Carl Hewitt at MIT, and first published in 1969. First subsets such as Micro-Planner and Pico-Planner were implemented and then essentially the whole language was implemented in Popler, and derivations such as QA-4, Conniver, QLISP and Ether (see Scientific Community Metaphor) were important tools in Artificial Intelligence research in the 1970s, which influenced commercial developments such as KEE and ART.
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