Secondary sources are interpretations, analysis, discussion, or evaluation of a subject. Often, a secondary source is from a time period that is different from the subject studied; it is a secondhand, not eyewitness, account of events, people, or subjects.
Journal articles and books are often formats of secondary sources, but some of these may report original research data, eyewitness accounts, or interviews, in which case they may be primary sources. Context is important for distinguishing between a primary or secondary source.
