Most history graduates are teachers in public and private schools, in universities, and in training programs. Other historians work as interpreters or educators in museums, libraries, national parks and historical sites. These roles require an understanding of history and culture, making public presentations, and a strong ability to communicate academic knowledge in an engaging way. Teachers also need to adapt material to different levels of student ability. They need to be able to assist others in developing critical thinking skills. Other opportunities exist as interviewers, surveyors, and research assistants in businesses, documentary projects, film and TV productions, education and public policy programs. Some historians might work for not-for-profit organizations in advocacy roles. Historians are a majority among curators, collection managers and archivists. They collect, study, and interpret unpublished documents, photographs and three-dimensional objects. This occupation requires an understanding of the historical context in which the records were created, the uses for which they were intended, their relationships to other sources, and their possible research use. They work in museums, archives, libraries and historical associations.