Glossary

Active partition

One of the primary partitions of a hard disk is usually active. Default MBR code tries to boot an operating system from the active partition of the first hard disk.

Basic disk

It is opposite to dynamic disk.

Cylinder

It is 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.

Dynamic disk

A Dynamic disk is a physical disk that provides features that basic disks do not have, such as supports for volumes spanning multiple disks. Dynamic disks use a hidden database to track information about dynamic volumes on the disk and other dynamic disks in the computer. Dynamic disk management is a data/Hard Disk management method on Microsoft Windows platforms, first introduced with Windows 2000 Operating System. The basic concept was put to use on UNIX platforms years earlier. There are five types of Dynamic volumes: Simple Volume, Striped Volume, Spanned Volume, Mirrored Volume, and RAID-5 Volume.

Extensible Firmware Interface (EFI)

Extensible firmware interface is a specification that defines a software interface between an operating system and platform firmware. Officially known as Unified EFI (UEFI), EFI is intended as a significantly improved replacement for the old legacy BIOS firmware interface historically used by all IBM PC compatible personal computers. The EFI specification was originally developed by Intel, and is now managed by the Unified EFI Forum.

GUID Partition Table (GPT)

GUID partition table is a standard for the layout of the partition table on a physical hard disk. It is a part of the Extensible Firmware Interface (EFI) standard proposed by Intel as a replacement for the outdated PC BIOS, one of the few remaining relics of the original IBM PC. The GPT replaces the Master Boot Record (MBR) used with BIOS.

File system

File system is a data structure that is necessary to store and manage files. File system performs the following functions: tracking free and occupied space, supporting folders and file names and tracking the physical positions of files on the disk. Each partition may be formatted with its own file system.

Geometry

It is a set of hard disk parameters that usually includes the number of cylinders, heads and sectors per track.

Head (magnetic head, read/write head)

It is a hard disk consisting of several magnetic platters, for each side of each platter there is a head used to read and write information on it.

Hidden partition

Hidden partition is a partition that is somehow made invisible to the operating system. Usually partitions are hidden by changing their types.

Label

It is an optional name that can be assigned to a partition to simplify its identification.

Logical partition

It is the partition information about which is not located in MBR, but in the extended partition table. The number of logical partitions on a disk is unlimited.

Master Boot Record (MBR)

Master boot record is a special place in the very first sector of the hard disk to store information about the hard disk partitioning and code to be loaded with BIOS. All the following actions depend on the contents of this code.

MBR partitions and GPT partitions

Partitions layout by MBR partition table are called MBR partitions; partitions layout by GUID partition table are called GPT partitions. Disk Copy 2.0 does not support GPT partitions. Disk Copy 2.0 regards partition as MBR partition if there is no special declaration.

Operating system

It is a set of programs that usually includes kernel, drives, shell, and system programs used for centralized hardware management and hiding the details of hardware management from the user and applications.

Partition

Partition is an independent area on a hard disk where a file system can be located. A partition can be either primary or logical, depending on its position in the partition structure. One of the primary partitions of a hard disk may be active. A partition has the following attributes: type, beginning and size. Besides, some partition managing software and booting managers allow hiding partitions. Information about partitions is stored in the partition table.

Partition structure

All the partitions on a hard disk make a tree rooted in the MBR partition table. Many operating systems and programs assume that any partition table but MBR may not contain more than one partitions and table entries, and it simplifies the partition structure greatly ¨C all the logical partitions from one chain.

Partition table

It is the table that contains the information about partitions and links to other partition tables. A partition table can not have more than four entries. Main partition table is located in the hard disk MBR, and the rest partition tables are called extended. Partition tables are usually stored in the first sector of a cylinder.

Primary partition

It is the partition information about which is contained in the MBR partition table. Majority of operating systems can be booted only from the primary partition of the first hard disk, but the number of primary partition is limited.

Sector

It is the minimal information unit on a disk transferred in single reading or writing operation. Usually a sector is 512 bytes large. A sector on a disk can be addressed in two ways: via the absolute number or via cylinder, head, and sector number on a track.

Track

Disks are divided into concentric circles called tracks. Information from one track can be accessed without moving the head.

Unrecognized disk

An unrecognized disk is a physical disk with incorrect partition table (Partition table defective, some partitions overlap, partition ends after disk end, etc).