Wikipedia:PRIMARYNEWS

In determining the type of source, there are three separate, basic characteristics to identify:

This page deals primarily with the last question: Identifying and correctly using primary sources.

The concept of primary, secondary, and tertiary sources originated with the academic discipline of historiography. The point was to give historians a handy way to indicate how close the source of a piece of information was to the actual events.

Importantly, the concept developed to deal with "events", rather than ideas or abstract concepts. A primary source was a source that was created at about the same time as the event, regardless of the source's contents. So while a dictionary is an example of a tertiary source, an ancient dictionary is actually a primary source—for the meanings of words in the ancient world.

There are no quaternary sources: Either the source is primary, or it describes, comments on, or analyzes primary sources (in which case, it is secondary), or it relies heavily or entirely on secondary or tertiary sources (in which case, it is tertiary). The first published source for any given fact is always considered a primary source.

The historians' concept has been extended into other fields, with partial success.

Imagine that an army conquered a small country 200 years ago, and you have the following sources:

Both the proclamation and the diary are primary sources. These primary sources have advantages: they were written at the time, and so are free of the opinions and fictions imposed by later generations. They also have disadvantages: the proclamation might contain propaganda designed to pacify the conquered country, or omit politically inconvenient facts, or overstate the importance of other facts, or be designed to stroke the new ruler's ego. The diary will reflect the prejudices of its author, and its author might be unaware of relevant facts.

The book and the journal article are secondary sources. These secondary sources have advantages: The authors were not involved in the event, so they have the emotional distance that allows them to analyze the events dispassionately. They also have disadvantages: In some topic areas the authors are writing about what other people said happened and cannot use their own experience to correct any errors or omissions. The authors may be unable to see clearly through their own cultural lens, and the result may be that they unconsciously emphasize things important to their cultures and times, while overlooking things important to the actual actors.

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