Canonical tags were introduced by all the major search engines in 2009. It was fairly unprecedented to have Google, Yahoo, and Microsoft unite to offer a solution to a problem. The canonical tag solves duplicate content indexation. If you are running Joomla CMS you have duplicate content. A Canonical tag is an HTML attribute that identifies a URL as being canonical to the page it is served on. The canonical tag looks like rel="canonical".
Microsoft Database Daemon
SyncServicesAgent