Windows - File Systems Overview
This document introduces the major file systems used by the Microsoft Windows family of operating systems and, explains how they differ from one another.
A file system is a method of organizing files on physical media, such as hard disks, CD's, and flash drives. In the Microsoft Windows family of operating systems, users are presented with several different choices of file systems when formatting such media. These choices depend on the type of media involved and the situations in which the media is being formatted. The two most common file systems in Windows are as follows:
NTFS
FAT
The NTFS file system
NTFS (short for New Technology File System) is a modern, well-formed file system that is most commonly used by Windows 2000, XP, and Vista. It has feature-rich, yet simple organization that allows it to be used on very large volumes.
NTFS has the following properties:
NTFS partitions can extend up to 16EB (about 16 million TB).
Files stored to NTFS partitions can be as large as the partition.
NTFS partitions occasionally become fragmentented and should be defragmented every one to two months.
NTFS partitions can be read from and written to by Windows and Linux systems and, can only be read from by Mac OS X systems (by default). Mac OS X, with the assistance of the NTFS-3G driver, can write to NTFS partitions. Installation instructions for the NTFS-3G driver can be found here: Mac OS X - Writing to NTFS drives
It is recommended that NTFS be used on all media whose use is primarily with modern Windows systems. It should not be used for devices which need to be written to by Mac OS X systems or on media that is used in devices which are not compatible with NTFS.
The FAT file system
The FAT (short for File Allocation Table) file system is a general purpose file system that is compatible with all major operating systems (Windows, Mac OS X, and Linux/Unix). It has relatively simple technical underpinnings, and was the default file system for all Windows operating systems prior to Windows 2000. Because of its overly simplistic structure, FAT suffers from issues such as over-fragmentation, file corruption, and limits to file names and size.
The FAT file system has the following properties:
FAT partitions cannot extend beyond 2TB.
Files stored to a FAT partition cannot exceed 4GB.
FAT partitions need to be defragmented often to maintain reasonable performance.
FAT partitions larger than 32GB are generally not recommended as that amount of space starts to overwhelm FAT's overly simplistic organization structure.
FAT is generally only used for devices with small capacity where portability between operating systems is paramount. When choosing a file system for a hard disk, FAT is not recommend unless you are using an older version of Windows.