Ory OAuth2 is a fully certified OAuth 2.0 and OpenID Connect provider that enables secure authorization and authentication for applications and APIs. It allows sharing of user identities across multiple apps, becoming a single sign-on provider, building third-party ecosystems, and connecting devices and services. Ory OAuth2 provides a standardized framework for handling authorization and authentication between different systems, helping authenticate users and authorize access to protected resources, APIs, and user data. It keeps track of user consent and grants limited access to resources without sharing user credentials, allowing customers to control which applications can access their data and to grant or revoke access at any time.