OIDC (OpenID Connect) is an identity layer built on top of OAuth 2.0 that enables secure authentication using standardized tokens. While OAuth focuses on authorization, OIDC specifies how clients verify user identity using ID tokens, userinfo endpoints, and discovery metadata. OIDC is widely used for single sign-on (SSO) across apps and services.
Why it matters
OIDC makes it easy to integrate secure, interoperable login flows without storing user credentials. It supports modern identity providers and enables consistent authentication across distributed architectures.
Examples
Using “Sign in with Google” or Azure AD SSO for enterprise applications. Lessons like Authentication Fundamentals complement OIDC learning.