Glossary
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Copyright © Acronis, Inc., 2000–2007
MBR can contain not more than one partition entry and one table entry. This simplifies
the partition structure greatly – all the logical partitions form one chain.
Partition table
. It is the table that contains the information about partitions and links to
other partition tables. A partition table cannot have more than four entries. The main
partition table is located in the hard disk MBR, and the other partition tables are called
extended. Partition tables are usually stored in the first sector of a cylinder.
Physical disk
. A disk that is physically a separate device. Thus, floppy disks, hard disks
and CD-ROMs are physical disks.
Primary partition
. The partition, information about which is contained in the MBR partition
table. The majority of operating systems can be booted only from the primary partition of
the first hard disk, but the number of primary partitions is limited.
Root folder
. The folder where the folder tree of a file system begins. Starting from the
root folder, one can uniquely describe the file position on the folder tree by sequentially
naming all the intermediate nested folders, e.g.: \WINDOWS\SYSTEM\VMM32.VXD. Here
the WINDOWS folder is a subfolder of the root folder, the SYSTEM folder is a subfolder of
the WINDOWS folder, and the VMM32.VXD file is located in the SYSTEM folder.
Sector
. It is the smallest information unit on a disk that is transferred in a single read or
write operation. Usually a sector is 512 bytes in size. A sector on a disk can be addressed
two ways: via the absolute number (see absolute sector) or via cylinder, head and sector
number on a track.
System disk/partition
is a disk/partition from which an operating system may be booted.
Such a disk usually contains the boot sector and system files of this operating system.
System file
is a file that contains the code and constant data for an operating system.
Each operating system has its own system file set.
System folder
. Some operating systems keep most of their files in a special folder on a
partition that may be different from the system one. For example for Windows 95/98/Me,
the IO.SYS system file resides on the system partition, while other system files are
located in the system folder, which is usually called WINDOWS. The Program Files folder
can also be treated as system since it resides on the same partition as WINDOWS and
also contains files that are relevant to the operating system.
Status
. A flag that shows if a partition is active. This flag is stored in the partition table
and has no meaning for logical partitions.
Track
. Disks are divided into concentric circles called tracks. Information from one track
can be accessed without moving the head.
User interface
is a set of principles, concepts and means by which programs interact with
the user. For example, in window interface all input and output is done in windows, and
the mouse is utilized quite often.
