Many academic journals incorporate a "peer review" or "referee" process in which other experts in the subject area examine journal articles before they are accepted for publication. A journal’s review board can send a paper back to the author with suggestions for improvement, which the author must make if the article is to be published.
Peer review makes it much more likely that the research described in a journal's articles is sound and of high quality. Note that "scholarly” and “peer-reviewed” are related but not the same: not all scholarly sources are necessarily peer-reviewed, but most peer-reviewed articles would be considered scholarly.
Youtube Video - Peer Review in 3 Minutes
Informative Picture - Anatomy of a Scholarly Article