Primary vs. Secondary Sources
What counts as a primary or secondary source differs by discipline.
In literature or literary criticism
a "primary source" is the text (novel, short story, play, poem, etc.) by the author you are researching.
A "secondary source" is a work about an author or his/her work, such as literary criticism, biographical information, or information about the historical context of the work.
a "primary source" is information created by a person who experienced the event. An example is a manuscript of a 19th century land treaty between the US government and a Native American tribe.
A “secondary source” is written by someone not personally involved, perhaps long after the event. An example is a book written by a historian about land treaties between the US government and that tribe during that time period.
Stories written in newspapers or magazines can be considered either primary or secondary. Such articles are usually considered primary if the author(s) express firsthand knowledge of the people and events involved.
In science, including social sciences
a “primary source” is original research that reports and interprets data collected by the author(s). Reports of such original research are often referred to as “empirical studies.”
A “secondary source” reports on results of data collected and analyzed by others. Secondary sources published in scholarly journals include literature reviews and meta-analyses. Articles in newspapers like the New York Times and magazines like Scientific American are secondary sources.