1936: Alan Turing publishes On Computable Numbers, introducing the concept of a universal computing machine (Turing machine)
1950: Turing publishes Computing Machinery and Intelligence, proposing the famous (and famously misunderstood) Turing Test as a measure of machine intelligence
1956: The Dartmouth conference (organized by John McCarthy, Marvin Minsky, Nathaniel Rochester, and Claude Shannon) officially coins the term Artificial Intelligence regarded as the birth of AI
1958: John McCarthy develops Lisp, a programming language designed for AI research
1965: Joseph Weizenbaum develops ELIZA, one of the first natural language processing programs simulating a psychotherapist. This is the original chatbot :). You can play with it here: Eliza
1966 - 1974 (AI winter 1): First period of reduced funding and optimism due to limited progress (e.g: failures in machine translation)
1970s: Expert systems arise (e.g MYCIN for medical diagnosis)
1980s: Commercial interest in expert system peaks. Japanese Fifth Generation Computer project begins
1987-1993 (AI Winter 2): Collapse of the expert systems market leads to another funding drought