UNOWN

An OpenID identity is just a URL. You can have multiple identities in the same way you can have multiple URLs. All OpenID does is provide a way to prove that you own a URL (identity). And it does this without passing around your password, your email address, or anything you don't want it to. There's no profile exchange component at all: your profiile is your identity URL, but recipients of your identity can then learn more about you from any public, semantically interesting documents linked thereunder (FOAF, RSS, Atom, vCARD, etc.).

Anybody can run their own site using OpenID, and anybody can be an OpenID server, and they all work with each other without having to register with or pay anybody to "get started". An owner of a URL can pick which OpenID server to use.

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