Q. Explain about FAT - Inode?

Today modern PC comprises total capacity of nearly 40GB for storage of program and data Due to this huge capacity in place of having just one operating system in our PC partitions are used to offer many separate areas within one disk each one treated as a separate storage device. Which means a disk partition is a sub-division of the disk in one or more areas. Every partition can be used to hold a different OS. Computer system boots from active partition and software provided permits the user to select that which partition is active one. 

For illustration we can run both Linux and Windows operating systems from same storage of the PC.

A new magnetic disk is only platters of a magnetic recording material. Before a disk can store data it should be divided in sectors that disk controller can read and write. This is known as low level formatting. Low level formatting fills disk with a special data structure for every sector that comprises a header, a data area, and a trailer. Low level formatting is placing track and sector information in addition of bad block tables and other timing information on disks. Sector interleave can be specified too at this time.