+Topical tags are indicated by preceding the tag name with the # character.
+This will create a link in the post to a generalised site search for the term provided.
+For example, #cars will provide a search link for all posts mentioning 'cars' on your site.
+Topical tags are generally a minimum of three characters in length.
+Shorter search terms are not likely to yield any search results, although this depends on the database configuration.
+The same rules apply as with names that spaces within tags are represented by the underscore character.
+It is therefore not possible to create a tag whose target contains an underscore.