A nofollow tag is a rel value that tells search engine bots not to pass ranking potential through a specific link. People can still see and follow the link, but search engines do not distribute ranking potential between the linked pages. Websites often use nofollow on areas they cannot fully control or trust, such as blog comments, forum posts, and guestbooks, to reduce the risk of link-related problems. The tag can be applied to both internal and external links.
