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NTFS replaced Microsoft's previous FAT filesystem, used in MS-DOS and early version of Windows. NTFS has several improvements over FAT such as improved support for metadata and the use of advanced data structures in order to improve performance, reliability and disk space utilization plus additional extensions such as security access control lists and file system journaling.

NTFS has three versions: v1.2 found in NT 3.51 and NT 4, v3.0 found in Windows 2000 and v3.1 found in Windows XP and Windows Server 2003. These versions are sometimes referred to as v4.0, v5.0 and v5.1, after the version of Windows they ship with. Newer versions added extra features: Windows 2000 introduced quotas. Windows version 95, 98, 98SE and ME, cannot natively read NTFS filesystems, although utilities do exist for this purpose.

For historical reasons, the versions of Windows that do not support NTFS all keep time internally as local zone time, and therefore so do all file systems other than NTFS that are supported by current versions of Windows. However, windows NT and its descendants keep internal timestamps as GMT/UTC and make the appropriate conversions for display purposes. Therefore, NTFS timestamps are in GMT/UTC. This means that when files are copied or moved between NTFS and non-NTFS partitions, the OS needs to convert timestamps on the fly. But if some files are moved when summer or "daylight" local time is in effect, and other files are moved when winter or "standard" local time is in effect, there can be some ambiguities in the conversions. As a result, especially shortly after one of the days on which local zone time changes, users may observe that some files have timestamps that are incorrect by one hour.

In NTFS, everything that has anything to do with a file (file name, creation date, access permissions and even contents) is written down as metadata. This elegant, albeit abstract approach allowed easy addition of filesystem features during the course of Windows NT's development - an interesting example is the addition of fields for indexing used by the Active Directory software. File Names are stored in Unicode ( UTF-16.)

Internally, NTFS uses binary treesTrees (structure) In computer science, a binary tree is an ordered tree data structure in which each node has at most two children. Typically the child nodes are called left and right''. One common use of binary trees is binary search trees; another is bi in order to store the file system data; although complex to implement, this allows fast access times and decreases fragmentation. A file system journal is used in order to guarantee the integrity of the file system itself (but not of each individual file). Systems using NTFS are known to have improved reliability, a particularly important requirement considering the unstable nature of the older versions of Windows NT.

Details on the implementation's internals are closed, so third-party vendors have a difficult time providing tools to handle NTFS. Currently, the Linux kernelLinux mascot Tux created by Larry Ewing. In computing, the Linux kernel is a free Unix-like operating system kernel created by Linus Torvalds in 1991 and subsequently improved with the assistance of developers around the world. It was originally developed includes a module which makes it possible to read NTFS partitions; however the general complexity of the filesystem and inadequate developer resources, both in time and persons, have delayed the addition of full write support. As a workaround, a project called Captive NTFS allows access to the NTFS by providing the operating system with an interface to the ntfs.sys driver which already exists on most NTFS partitions (and on all Windows NT installations). Though this provides slow read/write support, a few people have reported data loss.

Microsoft currently provides a tool to convert the FAT32 format to NTFS but not the other way around. PartitionMagicPartitionMagic is a computer program for hard disk drive partitioning originally made by the company PowerQuest but now owned by Symantec. It runs on the Microsoft Windows operating system and enables creation and modification of partitions. Already exist [1] by PowerQuestPowerQuest now owned by Symantec, is a vendor producing file system related software tools. Among their most notable products is PartitionMagic. External links . and the open source NTFSResize utility are both capable of resizing NTFS partitions.