Peer-Reviewed or Not
Your instructor may ask that you use a certain number of peer reviewed articles in your research paper, so what is a peer reviewed article?
All peer reviewed articles are scholarly, but not all scholarly articles are peer reviewed. What makes a peer reviewed article different?
Peer review is a rigorous process that some academic journals utilize to ensure that they are publishing reliable, original research. An article is reviewed (usually anonymously) by experts in the field who judge the quality and significance of the research, and then they decide whether the article is worthy of publication in the journal.
Oftentimes, the reviewers will request changes, and the revised article will be submitted again. Rejection is common - the more prestigious the journal is, the higher their rejection rates. Peer review is not perfect, and errors can still slip through the cracks, however the process is designed to be as thorough as possible.
Note
Peer-reviewed sources are most often articles, though you may see peer-reviewed conference papers as well.
Peer reviewed scholarly articles are considered one of the most reliable sources of trustworthy information that you can use.