Lecture 15 on artificial intelligence. This lecture begins by defining artificial intelligence, and then describes broad classes of actions that require "intelligence" (Planning, Learning, Natural Language, etc). Lastly, it introduces the Turing test as a test for artificial intelligence. A webcast of Lecture 15 is available athttps://coursesharing.org/courses/6/lectures/22 See an alternate version of lecture materials at http://inst.eecs.berkeley.edu/~cs10/fa10/lec/21/