FAT(File Allocation Table)

                                  FAT (File Allocation Table)

FAT (File Allocation Table) Or FAT is a computer file system architecture now widely used on many computer systems and most Memory Cards.

We use with digital cameras, flash drive, Floppy disks and many portable devices because of its simplicity.

Performance:

Performance of FAT compares poorly to most other file systems as it uses overly simplistic data structure, making file operations time-consuming.

 It also makes poor use of disk space in situations where many small files are present.

History

The Fat file system was developed by Bill Grates & Marc McDonald during 1976-1977.

The FAT file system was created for managing disks in Microsoft Standalone Disk BASIC.

Types:

1. FAT12

2. FAT16

3. FAT32

                             

Here we all talk about newer version of FAT32 which was introduced by Microsoft with cluster (To limit the size of the table, disk space is allocated to files in contiguous groups of hardware sectors called clusters) values are in 32-bit field , in which 28-bits are used to hold the cluster number ,for maximum of approximately 268 clusters. This means it allows for drive of up to 8 terabytes with 32KB clusters. The boot sector uses a 32-bit filed for the sector count limiting size of volume to 2 TB on your hard disk with 512 byte sector.
The maximum possible size for a file on a FAT32 volume is 4 GB minus 1 byte (2³²−1 bytes). Video applications, large databases, and some other software easily exceed this limit. Larger files require another formatting type such as NTFS.

FAT 32 Can be converted to NTFS .If there is more than one operating system then it will be better to convert some volume to FAT32.Use of multiple operating system on same hard disk would make FAT32 a better choice .
FAT32 doesn’t have
-- File level encryption.
-- Sparse file support.
-- Disk usage Quotas.
-- Distributed link tracing.
-- File Compression.
-- Hierarchical storage Management.

References:-
FAT(File Allocation System)