With single sign on a user can use a single login credentials to log into the other trusted web resources/website between organization and other websites (with the use of external identity management system). You don't have to remember multiple passwords.
With single sign on a user can use a single login credentials to log into the other trusted web resources/website between organization and other websites (with the use of external identity management system). You don't have to remember multiple passwords.
More @ http://wiki.developerforce.com/page/How_to_Implement_Single_Sign-On_with_Salesforce.com