Social science is a major category of academic disciplines, concerned with society and the relationships among individuals within a society. It in turn has many branches, each of which is considered a "social science". The main social sciences include economics, political science, human geography, demography, psychology and sociology. In a wider sense, social science also includes some fields in the humanities such as anthropology, archaeology, jurisprudence, history, and linguistics. The term is also sometimes used to refer specifically to the field of sociology, the original 'science of society', established in the 19th century.