Recovery Manager (RMAN) is a utility in Oracle that is generally used to backup, restore or recover database files. It performs backup and recovery by using database server sessions. The metadata about its operation may be stored in a control file of the target database or in recovery catalog schema in Oracle database. By default, RMAN automatically stores the metadata in the control file of the target database; so using a recovery catalog database is fully optional though it is encouraged to use a recovery catalog database so that if the production machine fails, we have the operations information in the catalog on a separate machine.