If you are looking for an answer to the question What is Artificial Intelligence? and you only have a minute, then here's the definition the Association for the Advancement of Artificial Intelligence offers on its home page: "the scientific understanding of the mechanisms underlying thought and intelligent behavior and their embodiment in machines."
However, if you are fortunate enough to have more than a minute, then please get ready to embark upon an exciting journey exploring AI (but beware, it could last a lifetime) …
... the technique of heuristic programmingis under detailed investigation as a means to the end of applying largescaledigital computers to the solution of a difficult class of problems currentlyconsidered to be beyond their capabilities; namely those problemsthat seem to require the agent of human intelligence and ingenuity fortheir solution. It is difficult to characterize such problems further, except,perhaps, to remark rather vaguely that they generally involve complexdecision processes in a potentially infinite and uncontrollable environment.If, however, we should restrict the universe of problems to those thatamount to the discovery of a proof for a theorem in some well-definedformal system, then the distinguishing characteristics of those problems ofspecial interest to us are brought clearly into focus.Proceedings of an International Conference on Information Processing. Paris:UNESCO House, 273-282.