Acronis disk director suite 9.0 User Manual

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Glossary
 
Copyright © Acronis, Inc., 2000–2005 
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Bootable partition. A partition that can host an operating system. At the 
beginning 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 greater the cluster size, the 
higher the losses due to file size adjustment, but the smaller the cluster the more 
space 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 another. 
Disc. A non-magnetic storage media (compact disc, CD-RW or DVD). 
Disk. A magnetic storage media (floppy disk or hard disk). (Note: Disc and Disk 
are often used interchangeably.)  
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, 
which describes physical files locations; a duplicate for higher data storage 
reliability follows FAT. 
The FAT also contains the disk cluster list, as well 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. 
The FAT describes each file by a chain of numbers — like serial numbers of a 
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 results in corresponding 
FAT changes.  
File system. Data structure that is necessary to store and manage files. A file 
system does the following functions: tracks free and occupied space, supports 
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 a description of files and other 
folders. Such a structure allows creation of a folder tree that begins with the root 
folder. 
Formatting. The process of creating a service structure on the disk. There are 
three levels of hard disk formatting: low-level (marking the magnetic surface with