This subcategory is for sites pertaining to the study of human communication and understanding. This field focuses on content and process of interaction, primarily among humans. Communication study consists of several subdisciplines. Some classify by the number of interactors: intrapersonal, interpersonal, small group, mass communication. Some classify by the type of interaction or problems inherent: intercultural, mediated, political, religious, organizational. Some classify according to the factors of interaction: rhetoric, language, semiotics, perception, cognition.