OAuth2 vs OpenID Connect: What are the differences?

What is OAuth2? An open standard for access delegation. It is an authorization framework that enables a third-party application to obtain limited access to an HTTP service, either on behalf of a resource owner by orchestrating an approval interaction between the resource owner and the HTTP service, or by allowing the third-party application to obtain access on its own behalf.

What is OpenID Connect? An authorization framework. It is a simple identity layer on top of the OAuth 2.0 protocol. It allows Clients to verify the identity of the End-User based on the authentication performed by an Authorization Server, as well as to obtain basic profile information about the End-User in an interoperable and REST-like manner.

OAuth2 and OpenID Connect can be categorized as "User Management and Authentication" tools.