A secondary source discusses, analyzes, and interprets a topic. Typically, in history, a secondary source will cite both primary sources and other secondary sources used to develop the author's argument. A historian's work, either a book or journal article, typically is a secondary source . Your senior thesis will be a secondary work.
You will want to use secondary sources for a couple of key reasons: 1) to gain a clear understanding of the events, time, people, places for a topic, and 2) to use the work cited to identify key primary sources.
Secondary sources are contextual. So, for instance, a newspaper article may be primary source for one topic (an first hand account from the time being studied) OR if could be a secondary source (discussion of an event that occurred in the past).
The databases listed here are places to start when searching for secondary sources.
The CRAAP Test (Currency, Reliability, Accuracy, Authority, Purpose) provides questions you can ask yourself to decide whether or not to include an article, book, website, or other type source in your research project.
The CRAAP Test is one tool to use when deciding on sources.
Adapted from "Evaluating Information – Applying the CRAAP Test." 29 Sept. 2009. Meriam Library, California State University, Chico. Web. 3 Sept. 2010.