Bootable partition. A partition that can host an operating system. In the be-
ginning of such a partition there should be a boot record.
Cluster. Information storage unit in such file systems as FAT and NTFS.
Every file occupies a certain number of whole clusters, so the more the clus-
ter size the higher the losses are that are due to file size adjustment, but the
smaller the cluster the more place do the cluster distribution tables occupy.
Cylinder. A group of all the tracks on all the magnetic platters of a hard disk
that can be accessed without moving the magnetic head. Access to the data
inside one cylinder is much faster than moving the head from one cylinder to
the other.
Disc. A non-magnetic storage media (compact disc, CD-RW, or DVD).
Disk. A magnetic storage media (floppy disk or hard disk).
Drive. A general word that can mean both a device for accessing information
on a disk (floppy disk drive) and a partition that can be accessed from an
operating system (logical drive).
File. A file is named information storage in the file system. In different file
systems, files can be stored in different ways, with different file names and
different ways to write the full path to the file in the folder tree.
File Allocation Table (FAT). The hard disk area, located after the boot sector,
that describes physical files locations; a duplicate for higher data storage re-
liability follows FAT.
The File Allocation Table also contains the disk cluster list. FAT contains as
many records, as there are clusters on a disk. If a FAT cell contains «0», the
cluster is empty. The last file cluster, defective cluster and reserved clusters
have their own special markings.
FAT describes each file by a chain of numbers — like serial numbers of file’s
disk clusters. The number of the first cluster of each file is stored in the
folder. Writing, deleting, and modifying files and folders implies correspond-
ing FAT changes.
File system. Data structure that is necessary to store and manage files. File
system does the following functions: tracks free and occupied space, sup-
ports folders and file names, tracks the physical positions of files on the disk.
Each partition may be formatted with its own file system.
Folder. A table in the file system that contains description of files and other
folders. Such structure allows creating folder tree that begins with the root
folder.
Formatting. The process of creating service structure on the disk. There are
three levels of hard disk formatting: low-level (marking the magnetic surface
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