Scholarly articles are pieces of writing intended by and for a scholarly audience - for researchers, professors, and students. These articles are usually found in journals, collections of articles on a topic that are published several times a year. Since scholarly articles are intended for people doing work in a specified field of research they usually have discipline-specific language, are written at least an undergraduate reading level, and usually have authors who are researchers in that field. They also usually draw on other scholarly articles as sources and list those sources in a bibliography or reference list at the end of the article. Scholarly sources are sometimes free to read online (or what's called "open access") but often they cost money to view - that's why you need to look for them in article databases purchased by the Library.
Watch the below video describing some of the differences between scholarly articles and popular articles, which are intended for the general public and are usually written so as to be understood by the average reader. Then, see the video that describes two types of scholarly articles: primary (or empirical) articles that usually describe original research studies; and review articles which examine many primary articles on a given topic and draw conclusions from all of them put together.
Watch this video (4:11) explaining the difference between popular and scholarly resources.
Both empirical (primary) and review articles are types of scholarly articles as defined in the video above. Watch the video below (3:35) to know the difference between these two types of scholarly articles.