File Allocation Table (FAT) is a file system invented and owned partly by Microsoft Corporation, for the use of MS-DOS. It is also the file system of all the non-NT core Microsoft windows. As the capability of the computer was limited at that time,
FAT file system was simplified. Therefore, it almost can be used by all the operating system of all personal computers.
Definition of FAT
File Allocation Table (FAT) is a file system invented and owned partly by Microsoft Corporation, for the use of MS-DOS. It is also the file system of all the non-NT core Microsoft windows.
As the capability of the computer was limited at that time, FAT file system was simplified. Therefore, it almost can be used by all the operating system of all personal computers. This superiority makes it become the ideal floppy and memory card file system. It also can be used in data exchange between different operating system.
However, FAT has a vital defect. When the file is deleted and the new data is written at the same place, their sections are usually scattered, which slow down read-write speed. Disk fragment reforming can solve the problem, but the recombination should be used frequently to keep the efficiency of FAT file system.
FAT also has the following defects:
1. Large capacity disk is a waste of space.
2. Low efficiency of disk utilization
3. Limitation of file store
4. Non-support of long file name, only for 8 characters.
5. Low security
Third-party support
Other IBM PC Optional operating systems such as
Linux, FreeBSD and BEOS are in support of FAT format, and most of them also quickly support
VFAT and
FAT32 format after the release of corresponding Windows version. The early edition of Linux includes UMSDOS format which is stored as an independent FAT called Linux with
Unix file attributes(
such as long file name and access permission).UMSDOS was stopped after the release of VFAT, and the function was forbidden since the use of core 2.5.7. Besides startup disk, the other volumes are also in support of FAT system.