A short description is a concise explanation of the scope of the page. We use descriptions in search suggestion, below each article title, and possibly by any community tools that uses our API.
Criteria
Here's a few brief rules:
- Be as brief as possible, preferably less than 40 characters.
- Focus on distinguishing the subject from similar ones rather than precisely defining it.
- Should be easy to read as it will be the first point of contact for many readers.
- Most important identifying information should be placed first.
- Should not be a full sentence unless absolutely necessary.
- Should be written as though it follows the title.
- Avoid duplicating information already in the title.
- No wikilinks, plain text only.
- Is not required to provide an adequate definition of the article subject.
- WikiProjects may find it useful to suggest standard formats which may be applicable to categories of articles.
- Avoid anything that is, or could reasonably be construed as, controversial or judgemental. Use universally accepted facts wherever possible.
- Use sentence case, starting with a capital letter. It is technically problematic to have to convert case when there may be proper nouns in the text.
For reference, please check 
Editing
Short description is easy to add and edit. Simply put a {{Short description}} template on the bottom of the page above the SEO template if it does not exist already. Note that some infobox templates generate a default short description, putting a short description template will override the generated one.
See also
- Wikipedia:Short description on Wikipedia