Introducing ‘Sign-in with Twitter’, OAuth-Style “Connect” « hueniverse OpenID is often described as a single-sign-on solution, or “the last username and password you will ever need”. OpenID is a federated authentication protocol – a protocol where users can use credentials from any compatible provider who can “speak” the OpenID protocol. But in this case, not any account will do. Twitter applications need Twitter accounts. in Public bookmarkswith oauthopenidprogsecuritytwitter