Before knowing how to use RMAN for backup and recovery, one should know why backup of files is required. One should remember that backup and recovery are one of the most important aspects in database administration. What is backup and recovery? It is a copy of the data which includes important parts of a database like redo log files, control files and data files. Normally back up is divided into two parts: physical backup and logical backup. Physical backup is the copy of physical database files. Logical backup contains data that is exported using SQL commands and stored in a binary file. Restoring a database generally refers to various operations in restoring, rolling forward and rolling back a backup. Regular backups prevent the loss of data and damage caused due to failure of disk drives, virus attack, power outrages and other network problems. No one is completely sure about when the failures may occur. One of the important reasons for failure is user error which may cause corruption or loss of valuable data. Another reason is media failure which can occur when the media, where the data files or transaction logs are stored, fails. Backup operations which are planned properly beforehand make the recovery process of the data very simple. Like this, there can be a number of reasons of failure.