Obscure/Rare knowledge is knowledge that is only understood by the most rigorous and practiced. It is generally not taught as part of standard education or learning, but the concepts and activities rely on a more integrated set of information. Sometimes it takes a more advanced discovery process to garner the knowledge, or it may be revealed as insights through mastering all previous capabilities. Among skilled professions, such levels of knowledge are usually possessed by trade/skill Masters. Obscure/Rare Knowledge encompasses Mastered Learning and Knowledge.