Important RMAN Commands in Oracle

The below mentioned are some of the important  RMAN commands used for backup related activities

RMAN >  list backup;
Shows a list of all the backups taken with RMAN utility.

RMAN >  list backup by file;
Shows a list  of all the backups by file type taken with RMAN utility.

RMAN> show all;
Shows all the current configuration parameters

RMAN> backup database;
This command backs up the target database

RMAN> backup database plus archivelog;
This command backs up the target database along with archivelogs

RMAN> report obsolete;
Shows all the backups that are obsolete (very old, not usable)

RMAN> delete obsolete;
Deletes all the backups that are obsolete

RMAN> Crosscheck archivelog all
Checks whether archived logs still exist on disk or tape

RMAN> Report need backup
Lists all datafiles in need of a new backup

RMAN> List Restore Point All;
Lists all restore points

RMAN> List Restore Point <restore_point_name>;
Lists a specific restore point

Check the link for many more important commands http://docs.oracle.com/cd/B14117_01/server.101/b10770/rcmsynta.htm