A journal that is peer reviewed or refereed utilizes scholars, researchers, or practitioners in the field to evaluate the strength of scholarship and overall quality of articles submitted for publication. Because of their expertise, peer reviewers can also comment on the relevance of the article to their field of study and the appropriateness of the article for the journal. As a result, articles in peer reviewed journals are often thought to be more authoritative than articles from non-refereed journals.
In contrast, magazines or journals that do not have a peer review process in place typically rely on an editor or editorial team to make decisions about whether an article will be published and, if so, what changes will be required.
It is also important to keep in mind that even in peer reviewed journals there may be content, such as news items, letters, and brief reports, that does not go through the peer review process.