Recovery Walk Through and User Managed Recovery

Walk through using RESTORE and RECOVER command to restore database from backup.
First, target db must be in a mounted state to perform a full database recovery. The database can be open if you are performing online tablespace recovery or something less than full database recovery.
SQL> startup mount

Run RESTORE and RECOVER command
RMAN> run
{
allocate channel c1 type disk;
restore database;
recover database;
alter database open;
}

User Managed Recovery
It is the traditional recovery method where you directly manage the database files required to recover the database using operating system commands.
Ex:
SQL> startup

You get an error saying that USERS01.dbf file is missing.

Restore the USERS01.dbf file, using cp command

SQL> startup mount
SQL> recover database;
SQL> alter database open;