File Systems Formats

File Systems tell computers how to store and retrieve data. It does this by organizing data into different pieces and categorizing for fast retrieval. Different companies such Apple and Microsoft will use different file structures for their operating systems. Some Files systems are built for specific use such as cash registers. Others are built from and resemble standards put in place by the industry. Below is a list of some of the characteristics of the most common files systems found on personal computers. These File Systems are generally used with hard discs, optical storage, and flash media. It is important to understand file system structures especially when using systems and computers that must share data between different structure styles.

NTFS

NTFS (short for New Technology File System) is a modern, well-formed file system that is most commonly used by Windows Vista, 7 & 8. 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 fragmented and should be defragmented often.
  • 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). Writing by Mac OS X systems can only be achieved through third party software by use of the NTFS-3G plugin.

It is recommended that NTFS be used for 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.

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. This section refers to the FAT32 file system. Some early versions of Windows 95 used the FAT16 file system, which had even more technical issues and stricter limitations. It is recommended that FAT16 is never used on any modern media. The FAT file system has the following properties:

  • FAT partitions cannot extend beyond 2TB.
    • NOTE: Windows cannot format a disc larger than 32 GB to FAT32, but Mac OS X can.
  • Files stored to a FAT partition cannot exceed larger than 4GB chucks.
  • 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.

exFAT file system

The exFAT (Extended File Allocation Table) is a Microsoft file system that is compatible with Windows and Mac OS 10.6+. It is also compatible with many media devices such as TVs and portable media players. exFAT has the following properties:

  • exFAT partitions can extend up extremely large disc sizes. 512 TiB is the recommended maximum.
  • Files up to 16 EiB can be stored on an exFAT partition.
  • exFAT is not compatible with linux/Unix.
  • exFAT partitions should be defragmented often.
  • exFAT cannot pre-allocate disk space.

HFS+ file system

HFS (Hierarchical File System) Plus is a file system developed by Apple for Mac OS X. It is also referred to as Mac OS Extended. HFS Plus has the following properties:

  • Maximum volume is 8 EB (about 8 million TB).
  • Files stored to HFS+ partitions can be as large as the partition.
  • Windows users can read HFS+ but not write.
  • Drivers are available that allow Linux users to read and writer to HFS+ volumes.

EXT file system

The extended file system was created to be used with the Linux kernel. EXT 4 is the most recent version of EXT. Extended file systems have the following properties:

  • EXT4 can support volumes up to 1 EiB.
  • 16 TB maximum file size.
  • Red Hat recommends using XFS (not EXT4) for volumes over 100 TB.
  • EXT4 is backwards compatible with EXT2 and EXT3.
  • EXT4 can pre-allocate disk space.
  • By default, Windows and Mac OS cannot read EXT file systems.