Historical intro to AI planning languages

This is my 2nd publication in field of Artificial Intelligence, prepared as a part of my project in AI Nanodegree classes. This time the goal was to write research paper about important historical developments in the field of AI planning and search. I hope you will like it . Planning or more precisely: automated planning and scheduling is one of the major fields of AI (among the others like: Machine Learning, Natural Language Processing, Computer Vision and more). To accomplish given tasks, these systems need to have input data containing descriptions of initial states of the world, desired goals and actions.