The text book definition for artificial intelligence is a machine is considered "intelligent" if it can pass the "Turing Test". So now you ask, "What's the Turing Test?" The Turing Test is where you hook up a computer to a teletype machine (or put the computer on the Internet). You then ask the computer questions via the keyboard. If you can not determine that the computer is non-human by asking it trick questions then the computer is "intelligent".

Along these lines I had a fun joke played on me years ago through a university computer. I was in a large publicly accessable room with many terminals attached to a main frame (a DEC TOPS-20). I was playing an ordinary game of "Adventure" on the computer when suddenly within the game a wizard appeared in a cloud of blue smoke. The wizard announced that he would answer any question I had concerning Adventure. I assumed the wizard was a program and started writing questions in standard Aventure syntax. The wizard quickly grew impatient with me. As his impatence grew, I responded by using more direct english. The wizard to my surprise was able to understand ordinary english. I continued doing this until I heard some guys laughing in the next aisle. I then realized that the "wizard" was actually a hack in the Adventure game executable and the guys in the next aisle (not the Adventure program) were talking to me. What was amusing about this joke was I found the wizard to be unbelievable because it had passed the Turing Test.

Gary