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Flash  Backup and Recovery Area
With ever decreasing cost of disk in the market place ,disk based backups are more feasible.  A The major advantage of flash backup and recovery area is once when the hard disk gets filled Automatically obslete backups are deleted reducing the need of DBA to do such tasks.
Or backups whose  archive logs have been already been backed up are automatically deleted

The flash Recovery area notifies the administrator when the disk space consumption is nearing the defined quota and there is  no more files to purge.

Incrementally Updated Backups
You can apply incremental backups to your datafile image  copies when you use the RMAN. This takes much less time  then performing  a full image copy of datafiles every day.
This is applied through two phases.

• Apply the incremental backup to datafile  image copies .This is done at database block level.
• Then apply the archive logs since the last incremental backup only .This is done at transaction level (Slower than previous phase)

Below you can see the example of incrementally updated Backups
Backup incremental level 0 tag = weekly database;    -- This takes a full database backup .
The remaining days .. The below script works which  creates a  incremental backup (Note the speed of incremental backup could be increased by using block change tracking file which is mentioned below ) and the  recover copy with tag weekly database   is used to add the incremental  to the  full backup .

Backup incremental level 1
For recover of copy
With tag weekly database;

Recover copy  of database
With tag weekly;

Faster Incremental Backup
Sql
alter database enable block change tracking using file ‘c:\cpisolution\bij.dbf’ ;

SWITCH DATABASE COMMAND.
The rman simply adjusts the pointers for the datafiles in controlfiles so they point to backup files in your flash recovery area. Advantage of this method is quicky recoverey.  No need to restore the data files from tape or hard disk.
Following are the commands for it
Restore Database to Copy;
Before applying this command the database  has to be in mount mode
You then recover the database using recover database command;
This will apply all the logs;

 Disadvantage is  it  is only a  temporary solution since
backups are stored in flash recovery area.

Global  Scripting
RMAN> print script full_backup to file 'my_script_file.txt'
Oracle Database 10g provides a new concept of global scripts, which you can execute against any database registered in the recovery catalog, as long as your RMAN client is connected to the recovery catalog and a target database simultaneously.
RMAN> create global script global_full_backup
{ backup database plus archivelog;
delete obsolete;
delete global script ‘full_backup’;
List Script Names;
Run  { Execute Global  Script  global_backup_db;}
Global RMAN Scripts

Duration Clause

BACKUP DURATION 4:00 PARTIAL
 MINIMIZE TIME DATABASE FILESPERSET 1;

You can limit the time the backup is going to takeplace by this command

Automatic Channel Failover
In Oracle 10g  the behaviour of  RMAN  changes with regard to the failure of a channel During  a RMAN backup . In Oracle Database 10g if a channel fails.  The backup process On that channel fails and will not be restarted.  However backups on remaining channels Will  continue to run.
Once the backup process is complete RMAN will report errors  that
Occurred during the backup process.

Compressed BackupSets
Backup as  compressed backupset  database;
Note that only backupsets can be compressed ( eg database,tablespace and datafile backups)
Specially image copies cannot be compressed. 

Rman >  configure device type  disk backup type to compressed backupset;
Binary compression technique reduces backup space usage  50-75 %

Recoverey Through ResetLogs
Prior to Oracle Database 10g it is recommended practice to make a full database backup following resetlogs. This is no longer required since backup can be used before resetlogs.

9 I New Features                                 

Persistent Rman Configuration
Configure This
Configure Retention Policty  To Recovery Window of 5 days
Retention Policy determines the  length of time   a backup is retained for use in a potential restore.
A recovery window  is a period of time that begins with the current time and extends backward  in time to point  of recoverability.

Configure Retention policy  to redundancy 3;
All backups older than  the most recent backup that satisfied the above conditions are obsolete.
The recovery window always  keeps in pace with the current time.
Specifying redundancy by using the CONFIGURE RETENTION POLICY TO REDUNDANCY command:
The REDUNDANCY parameter specifies that any number of backups or copies beyond a specified number does not need to be retained.
For example, the CONFIGURE RETENTION POLICY TO REDUNDANCY 3; command specifies that a maximum of three backups or copies of a data file or control file can be retained. Redundancy is the default type of retention policy.

Configure Backup Optimization On
Read only tablespace or datafiles  are backed only  once per recovery window
Configure RMAN to back up the control file after each backup
RMAN> CONFIGURE CONTROLFILE AUTOBACKUP ON;
By default, RMAN automatically names control file backups and stores them in the flash recovery area.
To configure RMAN to write control file backups to the /test directory:
( %F will generate a unique filename)
RMAN> CONFIGURE CONTROLFILE AUTOBACKUP FORMAT
FOR DEVICE TYPE DISK TO '/test/cf%F';

Block Media Recovery
Allows specified blocks to be recovered without affecting the entire datafile..  It is only intended for use where a  known and limited number of block is affected. This results in a reduced mean time  to recover (MTTR)  and higher availability as only the affected blocks are offline during operation
The information regarding which block has to be recovered in found in

The alert log file, Trace File,Analyze Table Command, Dbverify utility,V$Backup_Corruption & V$Copy_Corruption command.
Example of Using Block Recovery in RMAN.
BLOCKRECOVER DATAFILE 3 BLOCK 121;

Trial Recovery
You can determine the outcome of a recovery before actually doing it for real by appending the work "test" to any recover command. The following command will cause Oracle to perform a dry-run of a recovery without actually changing any data:

SQL> recover database until cancel test; 

Oracle Enterprise Manager
has also been configured in such a manner that it makes it easy to manage  all rman backups and restore operations.
It has  buttons for quick  crosschecks,  showing current backups, implementing fast recovery ,changing basic rman configuration ,etc

Archive Log Failover
Archive log failover allows RMAN can take advantage of multiple archive logs destinations such that, if a corrupt log is detected it can read the log from the alternate destination

Obselete
Delete obselete;  will delete all obselege backups.
Expired are those backups which donot exist in the media.

Auto Backp of Control file
Whenever there is a  structure change
Aditonally It Supports

• Backup of Server Parameter File
• Parrallel Operation Supported
• Extensive Reporting Available
• Scripting
• Duplex Backup sets
• Corrupt Block Detection
• Backup archive Logs