Searching and locating information sources is only one part of the research process. An equally important part is being able to tell if the sources you've located are trustworthy, appropriate, and authoritative.
Use critical thinking skills to decide what you trust.
Remember: source evaluation is along a sliding scale.* While there are some sources that a majority will agree are "good" or "bad" most information falls somewhere in between these two extremes. Often your assignment or the question you are trying to answer will help you determine what "good" and "bad" sources are.
*A silly example of a sliding scale, The Trustworthiness of Beards by Matt McInerney. Click to embiggen.
Scholarly articles are typically published in peer-reviewed journals, contain extensive bibliographies, clearly indicate the author and their credentials, and are written at a level intended for other experts in the field.
Popular articles typically have eye-catching graphics, are written for a layperson, lack indications of the author's expertise, and do not contain an extensive bibliography.
The following sites have more information regarding the differences between scholarly and popular sources of information:
Primary: Eye-witness account - i.e. results are reported for the first time by the authors/researchers.
Types: research articles, conference papers, lab notebooks, proceedings, technical reports, theses, and studies.
Secondary: A second-hand report - i.e. results are summarized, interpreted, or commented upon by others who were not witnesses or participants.
Types: review articles, encyclopedias, magazine articles and text-books.
Warning signs that you are reading a secondary source:
Reused under a Creative Commons BY-NC-SA license from NCSU Libraries
Adapted from the original CRAP test.
Catherine Hadler/freedigitalphotos.net