An Anthropologist is a scientist who researches and studies sociohistorical, archaeological, linguistical and biological aspects of humanity, especially as they apply to the development of modern man. In deciphering and analyzing artifacts, ancient languages and past cultures, anthropologists gain a better understanding of how modern civilizations and behaviours came to be. Theories surrounding anthropological studies are then applied to social policies, public problems and even government and military protocol. Anthropology as a science is divided into four distinct sub-fields: cultural anthropology (social anthropology), archaeology, linguistic anthropology, and biological (physical) anthropology. Depending on the sub-field, anthropologists' responsibilities vary widely. Social Anthropologists, for instance, research and study only social and cultural behaviours. They may be employed as social scientists for government or research laboratories, conducting surveys and analyzing data to develop new and more effective social policies. Census studies, for example, are often conducted by social anthropologist. In the field of Archaeology, anthropologists uncover humanity's hidden history through the discovery of artifacts and structures left behind by previous civilizations. They contribute supporting evidence to historical documents, or even uncover stories from the past that have not yet been told. Linguistic Anthropologists research language development and how it applies to modern cultures. Those employed in the science of biological anthropology study the development of the human species, especially theories that homo sapiens may have evolved from other primates. The duties of Anthropologist includes to be Collect information and make judgments through observation, interviews, and the review of documents. They also plan and direct research to characterize and compare the economic, demographic, health care, social, political, linguistic, and religious institutions of distinct cultural groups, communities, and organizations. It also involves to develop intervention procedures, utilizing techniques such as individual and focus group interviews, consultations, and participant observation of social interaction. They also conduct participatory action research in communities and organizations to assess how work is done, and to design work systems, technologies, and environments.