 Sometime during your research, your professor may ask you to use a primary or secondary source. But what is a primary source and what distinguishes it from a secondary source? A primary source is a firsthand account of a topic usually created by someone with direct knowledge of the event or topic described and created during the time period being studied. Examples of primary sources include original research studies, statistics, data, diaries, letters, interviews, art, literature, maps, videos, legal documents, government documents, and even a tweet or other form of social media. Secondary sources analyze, interpret, and synthesize primary sources. Examples include books and scholarly or magazine articles that analyze previous findings. However, it's important to keep in mind that whether a source is a primary or a secondary source will depend on the context in which it is used. Also, primary and secondary sources are different depending on the discipline or subject area. For example, original scholarly research articles are considered primary sources in the sciences and social sciences but are generally considered secondary sources in the humanities. Let's say you are conducting historical research about the women's suffrage movement and in the library you find a collection of letters written by historical women's suffrage leaders detailing their strategies and emotional appeals for equality. Those letters will be considered a primary source because they offer first-hand accounts of the event you are studying written by people with direct knowledge of the event and written at the time the event occurred. Later, you find a scholarly book on the topic of women's suffrage written by a researcher from 2020. It is considered a secondary source because it does not come from the time period you are researching and does not offer first-hand evidence of the event. Instead, it analyzes, synthesizes, and interprets various primary sources about the event to make its argument. Now let's say you are writing a research paper for your health sciences class about infectious diseases and you find several scholarly articles describing original research about new treatments for the flu virus. Those would be considered primary sources because they provide a full description of original research and were written by scholars with direct knowledge of the topic. You also find a book about the flu that offers a comprehensive overview of the subject. That's considered a secondary source because it synthesizes, analyzes, and interprets previous research findings. If you still have any questions about primary and secondary sources, ask an IRSE librarian.