1991 Definition of Primary and Secondary Information Sources

Information may be categorized into primary and secondary material. If information is new and has never been published before it research, new legislation and survey results, like government is termed primary. It includes original statistics. Primary information is always up-to-date, detailed, accurate and specialized. Consequently, fewer people want to use it and it tends to be expensive.

Information produced when scientists re-work primary material for a special purpose, like writing a skills textbook, or compiling an encyclopaedia, is termed secondary information. As a result secondary publications tend to be less specialized and cheaper to buy. They have a wider readership and are more accessible. It takes time to go through a great many primary sources and mistakes may be made in copying out data. Secondary work is, therefore, sometimes out-of-date and inaccurate. This is not to deny the value of textbooks and similar material—they are an excellent source of information. You should, however, be aware of their limitations.

It is important that you can recognize and distinguish new information from old. This is often difficult; a scientist when describing new research results (primary information) may refer to, and comment on, work published by others (secondary information).

Interesting to observe that WWW is still mostly working with Secondary sources, news coverage and articles about the primary information, instead of going to the mostly readily-available primary sources.