Primary Partition vs Extended Partition

A hard disk drive can be divided in to several storage units. These storage units are called partitions. Creating partitions would make a single physical disk drive appear as multiple disks. Software that can be used to create, delete and modify partitions is called a partition editor. Creating partitions would allow the user files to be resided separately from the operating system and other program files. Furthermore, partitions would allow the user to have multiple operating systems to be installed in different partitions of the same hard disk. Initially, a hard disk drive could be divided in to two partitions called the primary partition and extended partition. Information about the partitions in a computer is included in the Partition table, which is located in the Master Boot Record.

↑

Extended Partition

What is Primary Partition?

A disk drive can contain a maximum of four primary partitions or three primary partitions and a single extended partition. One file system is contained in a primary partition. Unlike earlier versions of Microsoft Windows systems, more recent Windows operating systems such as Windows XP, Windows 7 could be placed on any partition. But the boot files should be located in a primary partition. Partition type code of a primary partition indicates information about the file system contained in the primary partition or the whether the partition has a special usage. When there are multiple primary partitions in a hard disk, only a single partition can be active at any given time and the other partitions will be hidden. If a drive needs to be bootable, it needs to be a primary partition.

What is Extended Partition?

Only a single extended partition can be contained in a hard disk. But the extended partition could be subdivided in to several partitions called logical partitions. Extended partition acts as a container for logical partitions. The structure of the extended partition (about the logical partitons contained within the extended partition) is described in the Extended Boot Record (EBR). After the logical partitions in the extended partition are formatted using a suitable file system they will become visible. Extended partition can be used for storing user data. This would protect the data from operating system crashes or corruptions.

What is the difference between Primary Partition and Extended Partition?

Primary partition is a bootable partition and it contains the operating system/s of the computer, while extended partition is a partition that is not bootable. Extended partition typically contains multiple logical partitions and it is used to store data. A disk drive can contain multiple primary partitions, but it can contain only a single extended partition. Multi – boot system can be created using several primary partitions. Generally, primary partitions are assigned the first letters in the alphabet as drive letters (such as C, D) whereas logical drives in the extended partition get the other letters (such as E, F, G).