Primary sources are documents or other objects from the time you are studying. They haven't been changed or modified in any way. These are documents that are created by the people who actually experienced the events or conditions being described.
Examples of primary sources:
Secondary sources describe, summarize, and review information from primary sources and other secondary sources. The author was not necessarily involved in the original event and may not have even been alive at the time. Examples of secondary sources:
PRIMARY source evidence provides historians with the facts to work with. Journals, documents, contemporary records such as newspapers, receipts, and even material evidence such as clothing or dishes all exist as facts, or Primary Source Evidence. This evidence is recorded by someone who personally witnessed or experienced the subject in question. For example, if I have a marriage certificate for a 13 year old girl and a 54 year old man dated 1660, the marriage certificate itself is primary source evidence, and the fact is simply that the marriage occurred in that year between those parties.
Now the tricky part. If I write a history which purports to tell the story of the girl and the man, the quality of my history is determined by the depth with which I examined the sources. What value I assign to such a marriage, what conclusions I draw about the social structure that permits it, the reasons it may have occurred, are all my conjecture, all SECONDARY, and if I draw those conclusions based solely on the marriage certificate, they may be incorrect. I did not witness the marriage nor live in the community in which it occurred. Secondary sources are histories or records compiled by someone who has reviewed the primary sources, and their value depends upon the quality and number of sources examined by the author to create the history.
I can write a good SECONDARY SOURCE history of the event which allows the reader to understand the story, a story they otherwise might never have encountered. To give my secondary account value, I must build up my conjectures by examining, say, the diary of the girl, the records of the man, the town records which discuss the event, the record of neighbors or close relatives, newspapers if they existed in that location at that time, etc. If I seek out all related documents, hunt for all the evidence surrounding this event, then I would have a more complete picture of what happened, and my secondary history would reflect that. However there is still an element of educated guessing. If you as a reader take all I write as FACT, you may be misled. Find the facts that underlie the stories. Learn to ask yourself, "How does the author know this?" and "Where did she get his information?" We want you to read with a critical eye.
WHEN IS A SECONDARY SOURCE CONSIDERED PRIMARY?
A book or an article which is secondary in nature (written by someone other than an eyewitness or contemporary) or even tertiary (written by someone who used secondary sources to compile the history) can be considered PRIMARY in certain types of studies.
For example, say I want to write a paper dealing with HOW Native Americans are portrayed in U.S. eighth grade social studies textbooks. I would analyze, say, ten textbooks in use today. Every reference to Native Americans would be noted and categorized based on some criteria. Perhaps the study would consider word choice, type of anecdotes included, and often most important, what is NOT included in the text. Then I would have evidence to draw conclusions about how the eighth grade social studies textbooks deal with Native American History.
The secondary sources have become my primary sources because I am not studying what actual events, I am studying the way in which those events are recorded by a particular group of sources. I am studying not the history (which would require me to seek out primary sources) but the history books (the manner in which they present the history).
credit: Pearcy, Thomas, and Mary Dickson. “The Nature of Evidence.” RESEARCH: Primary and Secondary Sources, 1997, www.wwnorton.com/college/history/ralph/research/prisec.htm.