Update is for use on articles that require updating. When you place the template on the page, you should leave a note within the template as to what, exactly, needs to be added to the article.
Note that if the article needs major copy-editing or general cleanup, Template:Cleanup is perhaps more appropriate. If it's a Doctor Who universe article with an out-of-universe or non-canonical perspective, you should use Template:Oou.
Usage
Type
{{Update|<reason>}}
for example
{{Update|The article gives no information about the character's experiences in Big Finish audio plays.}}
at the top of the article requiring attention. Hence:
The article gives no information about the character's experiences in Big Finish audio plays.
These omissions are so great that the article's factual accuracy has been compromised. Check out the discussion page and revision history for further clues about what needs to be updated in this article.
Categorization
Articles tagged with this template are automatically placed within Category:Articles in need of major additions