The NTFS file system was launched with Windows NT 3.5 in 1993. Until Windows 2000, the development lines were kept strictly separate, and the end-user range of Windows 95, 98 and Me envisaged FAT 16 or FAT 32. By contrast, the NT series, including Windows XP, can handle all variants - except for Windows NT 4, which does not convert to FAT 32. There is a plethora of professional tools to work around this inability to read data on NTFS partitions under older Windows versions. One of the highest-quality and best-known tools of this type is Ntfsdos, which you can even use to boot up NTFS partitions by DOS diskette.

NTFS brings a host of improvements over FAT systems. The most important are optimized memory utilization in larger volumes, error correction following crashes, protection against unauthorized data access, an index service, compression and data encryption. The recovery characteristics of NFTS deserve special mention: Windows records in real time all modifications to the file system with checkpoints that it then uses to background-correct system errors in the event of a forced reboot. NTFS can manage partitions of several hundred teraBytes (one teraByte is one million megaBytes). As for security, administrators benefit mainly from the integrated protection functions such as the user access policies for files and folders, and EFS (Encryption File System).