Historians research events, people, technologies, ideas and other topics from the past. They collect data from a wide variety of sources, which can be cross-checked with other sources to check accuracy and find discrepancies. Historians interpret this information to suggest theories and draw conclusions about the subject. Their findings can be published through reports, books, journal articles, in the media, presented as lectures or form part of a museum exhibition. Many historians also undertake teaching duties at universities or schools. They may also act as an adviser or consultant to governments and other organisations, such as churches, private businesses or individuals.