The way the classification works is as follows:
- Featured Article: The article has attained featured article status by passing an official review. It is Professional, outstanding, and thorough; a definitive source for encyclopedic information. No further content additions should be necessary unless new information becomes available; further improvements to the prose quality are often possible.
- A-Class Article: The article is well organized and essentially complete, having been reviewed by impartial reviewers from this WikiProject or elsewhere. Good article status is not a requirement for A-Class. It is very useful to readers. A fairly complete treatment of the subject. A non-expert in the subject would typically find nothing wanting. Expert knowledge may be needed to tweak the article, and style problems may need solving. Peer review may help.
- Good Article: The article has attained good article status by passing an official review. It is useful to nearly all readers, with no obvious problems; approaching (but not equalling) the quality of a professional encyclopedia. Some editing by subject and style experts is helpful; comparison with an existing featured article on a similar topic may highlight areas where content is weak or missing.
- Bplus-Class Article: Detailed, clear and accessible, often with history or images; possible good article nominee. It is useful to nearly all readers. A good treatment of the subject, which attempts to be as accessible as possible, with a minimum of jargon. No obvious problems, gaps, excessive information.
- B-Class Article: The article is mostly complete and without major problems, but requires some further work to reach good article standards. Readers are not left wanting, although the content may not be complete enough to satisfy a serious student or researcher. A few aspects of content and style need to be addressed. Expert knowledge may be needed. The inclusion of supporting materials should also be considered if practical, and the article checked for general compliance with the Manual of Style and related style guidelines.
- C-Class Article: The article is substantial, but is still missing important content or contains much irrelevant material. The article should have some references to reliable sources, but may still have significant problems or require substantial cleanup. Useful to a casual reader, but would not provide a complete picture for even a moderately detailed study. Considerable editing is needed to close gaps in content and solve clean-up problems.
- Start Article: An article that is developing, but which is quite incomplete and, most notably, lacks adequate reliable sources. It provides some meaningful content, but most readers will need more. Providing references to reliable sources should come first; the article also needs substantial improvement in content and organisation.
- Stub Article: A very basic description of the topic. It provides very little meaningful content; may be little more than a dictionary definition. Any editing or additional material can be helpful. The provision of meaningful content should be a priority.
Finding out an article's classification can be a very helpful way for a student to decide whether the information and most importantly the sources in an article are reliable and could be used in their own research. To find out more details about the classification criterias, follow this link.