Periodical is a term used to describe any publication that is published multiple times (periodically). Periodicals include materials such as popular magazines, scholarly journals, and newspapers.

It is important to understand the difference between a popular and a scholarly periodical. When you are doing research, most of your sources should be scholarly.

Often popular periodicals are called magazines and scholarly periodicals are called journals. Many times it will be acceptable to use some popular material, but research papers should not be based solely on popular literature.

Criteria	Popular Magazine	Trade Journal	Scholarly Journal
Example
Content	Secondary discussion of someone else's research; may include personal narrative or opinion; general information, purpose is to entertain or inform.	Current news, trends and products in a specific industry; practical information for professionals working in the field or industry.	In-depth, primary account of original findings written by the researcher(s); very specific information, with the goal of scholarly communication.
Author	Author is frequently a journalist paid to write articles, may or may not have subject expertise.	Author is usually a professional in the field, sometimes a journalist with subject expertise.	Author's credentials are provided; usually a scholar or specialist with subject expertise.
Audience	General public; the interested non-specialist.	Professionals in the field; the interested non-specialist.	Scholars, researchers, and students.
Language	Vocabulary in general usage; easily understandable to most readers.	Specialized terminology or jargon of the field, but not as technical as a scholarly journal.	Specialized terminology or jargon of the field; requires expertise in subject area.
Graphics	Graphs, charts and tables; lots of glossy advertisements and photographs.	Photographs; some graphics and charts; advertisements targeted to professionals in the field.	Graphs, charts, and tables; very few advertisements and photographs.
Layout & Organization	Informal; may include non-standard formatting. May not present supporting evidence or a conclusion.	Informal; articles organized like a journal or a newsletter. Evidence drawn from personal experience or common knowledge.	Structured; includes the article abstract, goals and objectives, methodology, results (evidence), discussion, conclusion, and bibliography.
Accountability	Articles are evaluated by editorial staff, not experts in the field; edited for format and style.	Articles are evaluated by editorial staff who may be experts in the field, not peer-reviewed*; edited for format and style.	Articles are evaluated by peer-reviewers* or referees who are experts in the field; edited for content, format, and style.
References	Rare. Little, if any, information about source materials is given.	Occasional brief bibliographies, but not required.	Required. Quotes and facts are verifiable.
Paging	Each issue begins with page 1.	Each issue generally begins with page 1.	Page numbers are generally consecutive throughout the volume.

Courtesy of Lili Kang at Gate Way Community College Library. Based on Scholarly vs. Popular Materials by Amy VanScoy, NCSU Library,

and Scholarly, Popular and Trade Journals by Jason Puckett & Lyn Thaxton at GSU.