OAuth2 vs OpenID Connect: What's the Difference?

OAuth2 and OpenID Connect are often mentioned together, and many developers assume they solve the same problem. In reality, they serve different purposes . Understanding the difference is essential when designing authentication and authorization systems. What OAuth2 Actually Is OAuth2 is an authorization framework . It allows an application to access resources on behalf of a user without sharing the user's credentials . Instead of sending a username and password to every service, the client receives an access token issued by an Authorization Server . That token can then be used to request resources from a Resource Server . Example scenario: A user allows a third-party application to access their data stored in another service. OAuth2 enables this delegation securely. Why OAuth2 Is Not Authentication A common misconception is that OAuth2 is used for authentication. OAuth2 does not tell an application who the user is . It only answers the question: Is this client allowed to access this r