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What's the difference between OpenID and OAuth?
What is really the difference between OpenID and oAuth? They look just the same to me.
I should clarify, I'm planning to use them in drupal, if that makes any difference. So I guess I'm bound by whatever module implementations are available in drupal.
If you have an account (with some private resources) in a website, you can log in with username/password couple. If an application would like to get some private resources, and if you don't want to give them your username/password, use OAuth.
But if you want to log in into multiple websites with a unique account, use OpenID.
(Some websites use OAuth like OpenID, and OpenID can be use like OAuth if you have some private stuff in your OpenID account)