A taxonomist explains the current classification system for all living things. Beginning with Aristotle's two kingdom division, today there are five kingdoms, with talk of changing to six. Uses the product groupings in a grocery store to clarify the concept. Looks at the differences of each kingdom: Monera, Protista, Fungi, Plantae, and Animalia. Stresses that the more we learn, the more likely this system will change yet again.