A Primary source is a first hand or eye witness account of an event. A primary sources enables a researcher to get a clear picture of what actually happened during an historical event or a particular time period.
A Secondary source is a source that analyzes, relates, evaluates, or criticizes based on information gathered from primary sources.
Examples of Primary Sources:
Newspaper articles
Letters
Manuscripts
Diaries and Journals
Transcripts
Speeches
Interviews
Memories
Documents produced by government agencies such as Congress
Photographs
Audio Recordings
Moving Pictures
Research Data
Artifacts
Examples of Secondary Sources:
Textbooks
Encyclopedias
Recently published articles on historical topics
Literature Reviews
Newspaper editorials or articles reporting on previous findings
Biographies
Commentaries
Books that include analysis, commentary, or criticism