What is a peer reviewed article anyways? What is the big deal about peer review? What is it? How does it work? Why do my instructors ask me to find peer reviewed articles to use in my paper?
If an article has been "Peer reviewed" it has earned a kind of authority and credibility from an academic/scientific community. It's a process that research has to go through before it is published. When we're talking about peer review, we're usually talking about scholarly and academic publications. They are usually original research -- research that's never been done before.
What do Peer Reviewed Articles Look Like?
Probably the most known peer reviewed journal is Nature. Take a look at the current issue of Nature -- notice that it has all kinds of articles of interest to a lot of people -- news, editorials, book reviews. Look at the "Research Articles" section. There you will see the peer reviewed articles from Nature such as:
Notice that the articles have "received" or "submitted", "accepted by" and "published" dates. These are the marking of peer reviewed articles -- finding these dates can be a quick and easy way of identifying peer-reviewed research. These articles also describe an original scientific study or experiment. They follow the scientific method and have sections with names like "Introduction", "Methodology", "Results", etc. Peer-reviewed articles often, but don't always, have multiple authors whose affiliations are given in the article.