OIDC (OpenID Connect)

An identity layer built on top of OAuth 2.0 that adds standardized user authentication to the authorization framework. In addition to access tokens, OIDC issues a signed ID token (a JWT) containing claims about the authenticated user such as sub, email, and name. It defines standard endpoints — authorization, token, userinfo, and JWKS — enabling interoperable single sign-on and identity federation across providers.