Industry cluster track.
1 - The first task to be done by the unit is used to format any drive in it.
The unit does this by writing in
disc surface a pattern of 1s and 0s - as magnetic indicators.
This pattern divides the disc in the radial direction
sectors and concentric circles.
Once the read / write moves forward and backward on the discs
turning, she reads the magnetic indicators to determine its position in relation to the data on the disk surface.
2 - The combination of two or more sectors (sector) in a (track) form a cluster or block.
The number of bytes in a
cluster may vary depending on the version of DOS used to format the disk and disk capacity.
A cluster is the smallest
part that DOS uses to store information.
Even if a file occupies only 1 byte, there will be a cluster of 256 bytes
to save this file.
The number of tracks and sectors and thus the number of clusters that can create unity in
surface of the disk determines the disc capacity.
3 - The unit creates a special file located in sector 0 of the disk.
(In the computer world, numbering starts
at 0 and at 1.) This file is the file allocation table or FAT (acronym for File Allocation Table), as is
known.
The FAT is where DOS stores the information about the directory structure of the disk and which clusters
are being used to store which.
In newer versions of DOS, an identical copy of the FAT is
kept in another location if the data in the first FAT is damaged.
Normally, you do not see the contents of any
FAT.
Source: Evolution of Computers
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