What is in fsck section in fstab?

Question

I have a basic understanding of fsck utility but what does "fsck" section in /etc/fstab denote? It has values 0, 1, 2 what are these values?

Googling says 0- it wont be checked 1- will be checked on boot 2- Now what is it?

Answer 1

From the fstab(5) man page:

   The sixth field (fs_passno).
          This field is used by the fsck(8) program to determine the order
          in which filesystem checks are done at reboot  time.   The  root
          filesystem  should be specified with a fs_passno of 1, and other
          filesystems should have a fs_passno of 2.  Filesystems within  a
          drive will be checked sequentially, but filesystems on different
          drives will be checked at the same time to  utilize  parallelism
          available in the hardware.  If the sixth field is not present or
          zero, a value of zero is returned and fsck will assume that  the
          filesystem does not need to be checked.