Performance Art encompasses a lot of variables. (A lot!) And, since there's nothing concrete to analyze, after the fact (like a painting to look at, a sculpture to walk around or a ceramic piece to pick up and hold), Performance Art defies easy description. Oh, and let's not go into the fact that no two Performance pieces are ever the same. One can never compare apples to oranges, let alone other apples...Still, after much cross-referencing, gnashing of teeth, begging for a quiet house and the help of Grove Art Online, the topic is set forth for you here.