"Academic journals are periodicals in which researchers publish their work. They are typically peer-reviewed journals, meaning that the work is reviewed and evaluated by other scholars prior to publication in an effort to ensure that only the best, most rigorously researched articles are published. Journal articles offer a window into the inner workings of a discipline. They demonstrate how social scientists formulate hypotheses, design empirical studies, analyze the observations they collect, and interpret their results." (Laubepin 2013)
What's in them?
Who writes them?
What do they look like?
Who reads them?
What are their advantages?
What are their disadvantages?
Popular: Inform and entertain the general public. Magazines like Time or Rolling Stone; or newspapers like the L.A. Times.
Scholarly: Disseminate research and academic discussion among professionals in a discipline. Journals such as Journal of Applied Communication Research. Usually peer reviewed or refereed.
Trade: Neither scholarly or popular sources, but could be a combination of both. Allows practitioners in specific industries to share market and production information that improves their businesses.
Image from http://www.webpages.uidaho.edu/info_literacy/modules/module1/1_6.htm