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To be able to use the full space of a disk using FAT16 we have to partition the disk and assign drive letters to each area. Although the later file systems can address up to 2 TB (terabytes), most drives are partitioned to keep the file allocation table to a reasonable size for extra security. For example, when storing data on a separate drive or partition, the backing up of data is quick as only the data and not the full system is being updated.

Partitioning a hard drive must be done before it can be used and before the introduction of CD-ROMs this was done by booting the machine with a DOS floppy disk and running fdisk. It is advisable not to run fdisk on your working computer just in case you destroy the partitions and you lose all your data. We will look at fdisk when we come to install systems on your practice computer.

A Windows system usually falls into two categories:

  • One primary partition using the full disk space. If this is the first drive to be configured, this is assigned the letter C.
  • One primary and one extended partition splitting the disk space into two areas. These areas do not need to be of equal size but be careful you do not make them too small as you cannot enlarge them without first destroying the existing partitions. If this is the first drive to be configured, the primary partition is assigned the letter C and logical drives are added to the extended partition. Splitting the extended partition depends on the size of the disk and what will be stored on the drive. For example, on a file server with both a sales department and a marketing department storing data on the same disk drive then having two logical drives, one for each department, means that the back-up and restoration of the data of each is independent of the other.