WEB1018 - Hyperlinks that point to a directory should end in a slash (/)
Each URL that points to a directory in a site should end with a slash mark (/).
Most pages in a site contain at least one hyperlink to a URL that points to a directory (such as www.proseware.com/news/). If several hyperlinks in which the URL target is the same directory are formatted differently, they may be treated as separate links.
Different hyperlinks in which the URL target is a directory, one of which ends with a slash mark (/), are indexed differently by search engines. For example, http://www.proseware.com/news and "http://www.proseware.com/news/" refer to the same directory, but would be analyzed as pointing to different directories.
Some search engines will correctly resolve differently formatted references to directory if it is declared in a canonical link.
For more information, see WEB1057 - Canonical links are not defined inside the <head> tag section
The following is an example of a correctly formatted hyperlink.