When searching for information in the sciences it is important to know that there are two main types of information you will encounter: primary and secondary sources.
Primary sources are resources that report the results of original scientific research, written by those who did the research, that has not been published anywhere else.
If a publication comments on, evaluates, or discusses the original research report, then it is a secondary source, not a primary one.
| Primary Source | Secondary Source | |
| DEFINITIONS | Original materials that have not been filtered through interpretation or evaluation by a second party. | Sources that contain commentary on or a discussion about a primary source. |
| TIMING OF PUBLICATION CYCLE | Primary sources tend to come first in the publication cycle. | Secondary sources tend to come second in the publication cycle. |
| FORMATS--depends on the kind of analysis being conducted. | Conference papers, dissertations, interviews, laboratory notebooks, patents, a study reported in a journal article, a survey reported in a journal article, and technical reports. | Review articles, magazine articles, and books. |
| Example: Scientists studying Genetically Modified Foods. | Article in a scholarly journal reporting methodology and results of an original research study on GMO foods. | Article or book analyzing, comparing, and commenting on the results of a number of original research studies. |
Source: The Evolution of Scientific Information (from Encyclopedia of Library and Information Science, vol. 26) & GTCC Library Guide.
