What last+found Directory in Linux Operating System | ext3 Corrupted or Damaged Files

What is Purpose of last+found Directory.
1)last+found it will store corrupted or damage files when the unclean Power failure occur or system shutdown occur.
2)when we create the ext3 file system.
'lost+found' directory is created.
under these directory if any of the file has been damaged or crash the files will be store under 'lost+found'.
3)After the unclean or power failure of the system when the system boot it will check the fsck command
last+found Directory ext3 file system in Linux.
Whenever we create new file system under linux /Unix it will create lost+found directory,
it will be used for file system check & repair fsck utility In .
When the file system is mounted,
we can't used fsck command.
fsck it will check