Volume (computing) - Differences Between Volume and Partition

Differences Between Volume and Partition

A volume is not the same thing as a partition. For example, a floppy disk might be accessible as a volume, even though it does not contain a partition, as floppy disks cannot be partitioned with most modern computer hardware. Also, an OS can recognize a partition without recognizing any volume associated with it, as when the OS cannot interpret the filesystem stored there. This situation occurs, for example, when Windows NT-based OSes encounter disks with non-Microsoft OS partitions, such as the ext3 filesystem commonly used with Linux. Another example occurs in the Intel world with the "Extended Partition". While these are partitions, they cannot contain a filesystem directly. Instead, "logical drives" (aka volumes) must be created within them. This is also the case with NetWare volumes residing inside of a single partition. In short, volumes exist at the logical OS level, and partitions exist at the physical, media specific level. Some times there is a one-to-one correspondence, but it is not guaranteed to be true.

It isn't uncommon to see a volume packed into a single file. Examples include ISO9660 disc images (CD/DVD images, commonly called "ISOs"), and installer volumes for Mac OS X (DMGs). As these volumes are files which reside within another volume, they certainly aren't partitions.