Featured articles are considered to be some of the best articles Wikipedia has to offer, as determined by Wikipedia's editors. They are used by editors as examples for writing other articles. Before being promoted, articles are reviewed as featured article candidates for accuracy, neutrality, completeness, and style, according to Wikipedia's featured article criteria.
Good articles are articles that are considered to be of good quality, but are not yet qualified as featured articles. Good articles meet Wikipedia's good article criteria, passing through the good article nomination process successfully. In short, they are written very well, contain factually accurate and verifiable information, are broad in coverage, neutral in point of view, stable, and illustrated, where possible, by relevant images with suitable copyright licenses. Good articles do not have to be as comprehensive as featured articles, but they should not omit any major facets of the topic.