FAT (File Allocation Table) refers to a data table that holds information about how and where files are stored on any one partition, a single storage device may have one or several partitions.

The file allocation table also gives its name to the file system architecture to which it belongs, FAT.

Although originally designed for use with personal computers by Bill Gates and Marc McDonald, due to its straightforward structure it has been adopted throughout the digital storage world, being the prominent file architecture used in memory cards for digital cameras, USB flash drives and other portable storage devices.

A single file on your hard drive, or other storage device, may not be stored in one place, the file could be split up and stored in several different (physical) places (this is called fragmentation). The FAT keeps a record of where the different parts of the file are stored.

Unlike the NTFS file architecture, the FAT system does not duplicate critical data, so if a critical sector is lost then it can mean the loss of all data within the partition.

FAT16 is a file system used in the first releases of Windows 95.

FAT32 is a file system used by later releases of Windows 95 and by Windows 98/98SE, it is also supported by Windows XP, Windows Vista and Windows 7.

Back to Computer Dictionary