What is the main difference between enterprise application and app registration?

Hello @Azurechamp , enterprise application is the friendly name for service principal. App registration is the friendly name for the actual application object, which is represented for authentication and authorization purposes by the service principal. This is why all app registrations need a service principal to be able to authenticate. Typically, if you develop applications that uses the Oauth2 or Open ID Connect protocols you will create an app registration. If you want to use an application from the gallery or if you want to develop a custom application that uses the SAML protocol, you will create an enterprise application. Both procedures create an application and a service principal but differ on the UI used in the Azure Portal.

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