NTFS

Short for NT File System or New Technology File System, NTFS is the standard file system of Windows NT, including its later versions Windows 2000, Windows XP, Windows Server 2003, Windows Server 2008, and Windows Vista. NTFS replaced the FAT file system as the preferred file system for Windows based operating systems and is therefore used for storing and retrieving files on hard disks. NTFS is the Windows NT equivalent of the Windows 95 file allocation table (FAT) and the OS/2 High Performance File System (HPFS), and it offers a number of improvements in terms of performance, extendibility, and security.

Notable features of NTFS include improved support for metadata and the use of advanced data structures to improve performance, reliability, disk space utilization plus additional extensions such as security access control lists and file system journaling. The NT File System also includes fault tolerance, which repairs hard drive errors without displaying error messages which can help prevent hard disk failure as well as make it possible to recover files if a hard drive fails.

The file system specification is a trade secret, although it can be licensed commercially from Microsoft through their Intellectual Property licensing program.