Perhaps the most distinguishing feature of an expert is that when given a novel problem to solve in his or her domain of expertise, the expert can solve the problem easily. Novices, on the other hand, are good at dealing with typical problems or "classic" cases, but not novel problems. In people, the evolution from novice to expert happens as a result of being able to introspect and examine the knowledge used in solving problems. That introspection and examination allows people to learn from experience. A human expert can interpret a new case in terms of something (either a previous case or generalized knowledge) he is already familiar with. This implies that as an expert is having new experiences, he is evaluating and understanding them in terms of past experiences. In the process, he is integrating the new experience into his memory so that it too will be accessible to use in understanding a later case.