The term authentication refers to the process of validating one's identity. Usually, users aren't created in OpenShift itself, but provided by an external entity, such as the LDAP server or GitHub. The only part where OpenShift steps in is authorization—determining roles and, therefore, permissions for a user. OpenShift supports integration with various identity management solutions used in corporate environments, such as FreeIPA/Identity Management, Active Directory, GitHub, Gitlab, OpenStack Keystone, and OpenID. For the purpose of brevity, we will only discuss the most commonly used ones, but you can refer to https://docs.openshift.org/latest/install_config/configuring_authentication.html for the complete documentation.