Primary sources are the original documents of an event or discovery such as results of research, experiments or surveys, interviews, letters, diaries, legal documents, and scientific journal articles. Primary sources are also records of events as they are first described.
Some examples of primary sources are:
*Newspaper articles that report on a recent event can be primary sources, but articles that rehash previous events are not primary sources, unless they add new information to the story.
Secondary sources offer an analysis or a restatement of an event or discovery described in primary sources. They interpret, explain or summarize primary sources. Some secondary sources are used to persuade the reader. Secondary sources may be considered less objective.
Examples of secondary sources include:
**Many academic articles include short literature reviews to establish a starting place or a jumping off point for their own, original research; these are still considered primary sources. However, articles that only review previously published articles and contain no new research are secondary sources; these articles are called systematic literature reviews and can be good sources of information about the state of research on a certain topic.