Q. What's a scholarly journal, academic journal, or peer-reviewed journal?

"Scholarly Journal" and "Academic Journal" are two words for the same thing.  Articles in these publications go through a "peer-review" process, which means their inclusion in the publication is decided by other experts in the same field rather than a general editor. (This video explains more). Many professors will require you to use scholarly sources because they are more credible than popular magazines or most websites.

Many databases label articles as being published in either a scholarly journal or a popular magazine. What's the difference?