Appears after an event occurs. Retrospective material may take the form of books or journal articles, but it always looks back on the event or topic. The time lapse involved in retrospective material provides a point of view that may be different from that provided by contemporary material.
Contemporary material Appears close to the time that an event occurs.
Contemporary material may take the form of magazine, journal, or newspaper articles. Contemporary material is essential when researching current event topics. For example, when writing a paper on the topic of Japanese internment camps during World War II, you might want to look at newspaper articles from the 1940s as well as retrospective material written since the conclusion of the war.