# File Allocation Table

> family of file systems originally developed by Microsoft

**Wikidata**: [Q190167](https://www.wikidata.org/wiki/Q190167)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/File_Allocation_Table)  
**Source**: https://4ort.xyz/entity/file-allocation-table

## Summary
File Allocation Table (FAT) is a family of file systems originally developed by Microsoft. It represents one of the earliest and most widely used file systems for personal computers, playing a crucial role in early storage management.

## Key Facts
- Developer: Microsoft
- Inception: 1977
- Type: File system (instance of)
- Known derivatives include: VFAT, FAT12, FAT16, FATX, and NetWare File System
- Has multiple language aliases including: VFAT, Tabla de asignacion de archivos, Sistemas de archivos FAT, and ファイルアロケーションテーブル
- Sitelink count: 45 (across various Wikipedia editions)
- Archwiki articles available in English, Russian, and Spanish
- Gentoo wiki articles available in English, Italian, Hungarian, Russian, Simplified Chinese, and Japanese

## FAQs
### Q: What is the File Allocation Table used for?
A: File Allocation Table is a family of file systems that provides a method for organizing and managing files on storage devices like floppy disks, hard drives, and USB flash drives.

### Q: When was the FAT file system first developed?
A: The FAT file system was originally developed by Microsoft in 1977, making it one of the earliest file systems for personal computers.

### Q: What are the main differences between FAT12, FAT16, and FAT32?
A: The numbers in FAT12, FAT16, and FAT32 refer to the number of bits used for file allocation entries. FAT12 uses 12-bit entries, FAT16 uses 16-bit entries, and FAT32 uses 32-bit entries, with each version supporting different maximum storage capacities.

### Q: How does FAT compare to other file systems?
A: FAT was designed to be simple and compatible across different operating systems, which made it widely adopted. Unlike more complex systems, it lacks features like file permissions and advanced security mechanisms, making it suitable for smaller devices and cross-platform compatibility.

## Why It Matters
File Allocation Table matters because it pioneered simple file storage management that became the standard for early personal computers. Its cross-platform compatibility allowed devices running different operating systems to exchange data seamlessly, fostering the growth of personal computing and removable media. FAT's lightweight design made it ideal for small storage devices where complex file systems would be impractical. Despite newer file systems with more features, FAT remains relevant in embedded systems, USB drives, and memory cards due to its simplicity and universal recognition.

## Notable For
- One of the earliest file systems specifically designed for personal computers in the late 1970s
- Exceptional cross-platform compatibility that enabled data exchange between different operating systems
- Designed with simplicity in mind, making it ideal for resource-constrained devices
- Long-lasting legacy that continues to be used in various modern applications despite more advanced alternatives
- Created by Microsoft, which used it as the primary file system for early MS-DOS and Windows operating systems

## Body

### Overview
File Allocation Table (FAT) is a family of file systems developed by Microsoft in 1977. It uses a simple table structure to track where files and directories are located on storage media. The original purpose was to provide a consistent way to manage data on floppy disks and early hard drives for personal computers.

### Technical Structure
The FAT file system maintains a table that maps file locations, with each entry representing clusters of data on the disk. This approach allows the operating system to locate file fragments even when they're stored in non-contiguous blocks of storage space. The simplicity of this design enables broad compatibility across different systems.

### Variants
The family includes several notable variants:
- FAT12: Uses 12-bit entries in the allocation table
- FAT16: Uses 16-bit entries, supporting larger partitions
- FAT32: Uses 32-bit entries, supporting even larger storage capacities
- VFAT: An extended version that supports long filenames
- FATX: A modified version used in Xbox game consoles

### Legacy and Usage
Despite being introduced in 1977, FAT remains in use today for various applications:
- Embedded systems where resource efficiency is critical
- USB flash drives due to universal compatibility
- Memory cards in cameras and other portable devices
- Boot drives for operating systems that need minimal requirements

### Industry Impact
FAT established fundamental concepts in file system design that influenced later systems. Its cross-platform nature helped standardize data exchange between different computer systems during the personal computer revolution. Microsoft's development of FAT played a significant role in establishing their dominance in early operating systems.

## References

1. Freebase Data Dumps. 2013
2. KBpedia