FDISK

For computer file systems, fdisk is a command-line utility that provides disk partitioning functions. In versions of the Windows NT operating system line from Windows 2000 onwards, fdisk is replaced by more advanced tool called diskpart. Similar utilities exist for Unix-like systems.

IBM introduced fdisk, Fixed Disk Setup Program version 1.00, with the March 1983 release of the IBM PC/XT, the first PC to store data on a hard disk, and the IBM Personal Computer DOS version 2.0. Version 1 could be used to create one FAT12 DOS partition, delete it, change the active partition or display partition data. fdisk writes the master boot record, which supported up to four partitions. The other three were intended for other operating systems such as CP/M-86 and Xenix, which were expected to have their own partitioning utilities as fdisk did not support them.

In August 1984, PC DOS 3.0 added FAT16 partitions to support larger hard disks more efficiently.

In April 1987, PC DOS/fdisk 3.30 added support for extended partitions, which could hold up to 23 "logical drives" or volumes.

Support for FAT16B was added with Compaq MS-DOS 3.31, and later became available with MS-DOS/PC DOS 4.0.

Most DOS fdisk programs, including the fdisk program that came with the original Windows 95, are only capable of creating FAT partitions of types FAT12, FAT16 and FAT16B.

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