Primary Source vs. Secondary Source
A primary source is a document that shows direct, immediate or firsthand knowledge of a subject or event. It is a document written at the time or on the scene where an event occurred.
Secondary sources are those writings without direct knowledge of a topic or event. These include biographies, monographs, and general periodical articles. Secondary sources are written by people who did not witness or experience an event but have a great deal of knowledge about the topic. Writers often use primary sources in their writing of secondary sources!
Oliver Wendell Holmes Library Catalog
ALWAYS use the date range feature when searching for primary source newspaper articles. An article is only a primary source if it was published at the time in which an event took place.
Always do reading in secondary sources before looking for primary sources. Often times, information in secondary sources will lead you to a primary source. For example, an article in a reference book might reference a speech or letter written by the person you are researching.