Search engines consider www.somedomain.com and somedomain.com to be two different URLs when they both go to the same location. This SEO enhancement prevents penalty for duplicate content by redirecting all incoming links to one or the other.
Prevents redirection for feeds, trackbacks, searches, and admin URLs. Does not redirect on non-pretty-permalink-supporting IIS 7+, page/post previews, WP admin, Trackbacks, robots.txt, searches, or on POST requests.
Will also attempt to find the correct link when a user enters a URL that does not exist based on exact WordPress query. Will instead try to parse the URL or query in an attempt to figure the correct page to go to.