Disk Administrator (usually located in Start, Programs, Administrative Tools) is a graphical tool for managing disks. This tool encompasses and extends the functionality of character-based disk management tools such as MS-DOS FDISK. Here are some of the things you can do with this graphical tool:

Create and delete partitions on a hard disk and logical drives within an extended partition. Format and label volumes. Read status information about disks such as the partition sizes and the amount of free space that is available for creating additional partitions. Read status information about Windows NT volumes such as the drive-letter assignment, volume label, file system type, and size. Make and change drive-letter assignments for hard disk volumes as well as CD-ROM devices. Create and delete volume sets. Extend volumes and volume sets. Create and delete stripe sets. Note: Disk Administrator cannot be used to further partition the system partition because it contains files required to operate Windows NT Workstation.