http://www.wondershare.com/disk-utility/format-recovery.html
Wondershare Data Recovery: Lost all your data after accidental formatting? Don't worry. Here is the guide helping you recover files after formatting completely and easily.
http://www.wondershare.com/data-recovery
In short, formatting is to initialize and prepare a storage medium such as a hard drive or flash drive to be recognized, read or written by computer. All hard disks should be formatted before use.
However, there are also some situations that you need to perform the format to make your disk available to use:
'Media/Drive is not formatted would you like to format now?'
Operating System not found
Invalid or corrupted or damaged FAT and NTFS partitions table
Cannot find file or program
nvalid command
Primary/Secondary HDD failure
Non system disk