A disk partition is a defined storage space on a hard drive. There are three kinds of
partitions: primary partition, extended partition and logical partition. All Windows
operating systems can let users divide a hard disk into multiple partitions. In this
way, users can allocate one physical hard disk into several smaller logical
partitions. To store classified data, multiple partitions on a disk can organize his
data more effectively. On the disk of a computer, the OS was installed in one
partition and the other partitions are created to store user data, documents or
games. The benefit of such arrangement is when a problem occurs to Windows system,
the OS partition can be totally overwritten and reinstalled, and this does not
affect the data partition.
Some users may split a hard disk into multiple
partitions because smaller partitions offer smaller cluster sizes. A cluster
size is the smallest chunk of data which a partition can store. A large partition
might have a cluster size of 64KB. This means that a file even with one word in it
will also occupy 64KB of space on the disk. In a smaller partition, that file might
only require 2KB to be stored. This is a useful policy if you need to save a large
number of small files. Yet, too small clusters will generate many disk fragments
during data read-write process. Thus, it’s better to choose a proper cluster size
according to your own condition.
You can create, delete and format partition through using the diskpart.exe command.
Many operating systems also have graphical tools which accomplish the same task such
as Partition Assistant, which is a free
partition manager. It not only can partition on a disk, but also resize/move
a partition to adjust the size of the partition to optimize disk space usage.
Partition is a part of a computer hard disk that functions like a
separate disk. Separate, formatted partitions share your computers’s memory and
storage space. Partitions allow you to install more than one operating system on
Volume is a storage area on a hard disk that is formatted with a file
system. Volumes have drive letters assigned to them. A single hard disk can have
multiple volumes while a single volume can also span multiple hard disks.
Tip:Usually, “partition” and “volume” can serve as alternative to
each other when we describe something about computer for they functions nearly the
same. The biggest difference is that “partition” is a term used for basic disk while
“volume” is for dynamic disk; and Windows system can’t be installed on dynamic
The following is Disk Partition Related Glossary
Primary Partition and Active Partition:
What is primary partition? A primary partition is in which an Operating System
can be installed. One MBR hard disk may contain a maximum of 4 primary partitions.
An active partition is based on primary partition. Any one of the 4 primary
partitions can be set as active partition. Since there can be 4 primary partitions
with 4 different Operating Systems installed, one of the partition that is marked
active is used for the initial booting. The active partition contains the boot
loader (such as ntldr or bootmgr) to load operating systems from a disk.
Primary Partition: A primary partition contains one file
system. In DOS and all early versions of Microsoft Windows systems, Microsoft required
what it called the system
partition to be the first partition. All Windows operating
systems from Windows 95 onwards can be located on (almost) any partition, but
the boot files (io.sys, bootmgr, ntldr, etc.) must reside on a primary
partition. However, other factors, such as a PC's BIOS (Boot
sequence on standard PC) may also impose specific requirements as to which
partition must contain the primary OS. (By Wikipedia)
Active Partition:The active partition is the
partition where theboot
flagis set. DOS and Windows allow only one boot partition to be set
with the boot flag. (By Wikipedia)
If there is only one partition installed system on a hard disk, then it is
automatically activated. If there are more than one system (more than one system
partition), users can manually set a
system partition as active partition.
Extended Partition and Logical Partition:
Because the primary only can be created four maximum, this need to use extended
partition to break the limitation of 4 partitions. In an Extended Partition you can
create unlimited logical drives. You can store data in the logical partitions
similar with primary partition, but the extended partition is not used to store
data, because the Extended Partition is used to hold logical partitions, at the same
time, there can only be one extended partition on a single disk.
Extended Partition: An HDD may contain only one
extended partition, but that extended partition can be subdivided into multiple
logical partitions. DOS/Windows systems may then assign a unique drive
letter to each logical partition.(By Wikipedia)
Logical Drive: Also called logical partition. A volume
created within an extended partition on a basic disk. A logical drive can be
formatted and assigned a drive letter, but cannot host an operating system. (By
Microsoft) fortunately, you canconvert logical
GPT: On a MBR disk, there can only be maximum
4 primary partitions or less than 4 primary partitions plus one extended
partition. On a GPT disk, there is no concept of primary or logical, thus, the
primary partition limitation does not exist.
The Rules of Partitioning a Hard Drive
A hard disk drive must be partitioned before you can use it. There are some rules as
- A maximum of four primary partitions can be created on any MBR hard disk. The
limitation of four primary partitions is that when one primary partition is
applied to the system the master boot record is structured.
- There is only one primary partition can be designated as active partition and
this partition is used to boot system.
- BIOS will only recognize the active partition for loading operating system.
Other partitions can’t be recognized.
- To break the limitation of at most 4 primary partitions, you have to create 3 or
less primary partitions plus an extended partition and there is only one extend
What is Partition Table?
Partition Table is a storage space which records some information about primary,
extended and logical partitions. Further, the create/delete/resize
of any partition all will modify the partition table to reflect the changes
permanently. If partition table is crashed by virus or other stuffs, you partition
will lost, so the table is extremely important.