Volume Definition

The word “volume” has several different meanings. The most common definition is the magnitude or intensity of a certain sound. Volume may also refer to how much space a three-dimensional object takes up. However, in the always ambiguous realm of computers, the word volume can also refer to a specific data storage device.

Some examples of volumes include hard disks, DVD drives, and flash memory drives, such as USB keychain drives. Your computer recognizes all these data storage devices as volumes. The only requirement is that each volume has a file system that the computer can recognize. The file system tells the computer how the folders and files are organized on the volume.

On a Macintosh, all volumes connected to the computer (either directly or by a network connection) will show up on the desktop. For example, a hard drive will have a hard drive icon and a CD will have a CD icon. In Windows, you will find a list of all available volumes when you open “My Computer.” If a volume is connected, but is not showing up on the screen, you can often use a disk utility program to “mount” the volume so that the computer can communicate with it.

In computer data storage, a volume is a single, accessible storage area that is treated by the operating system as a distinct unit for storing files.

A volume is a logical entity that has a single, consistent file system (like NTFS, exFAT, or APFS) and a defined storage capacity.

Volume vs. Partition

While the terms are often used interchangeably, especially in older or simpler systems, they have technical distinctions:

Feature	Partition	Volume (or Logical Drive)
Level	Physical/Media-Specific	Logical/OS-Level
Definition	A raw, contiguous section of a physical disk (HDD or SSD). It defines where a storage space begins and ends.	A formatted storage area with a file system. It’s the space the OS actually uses to read/write files.
Accessibility	Usually not directly accessible by users until a volume is created on it.	The accessible unit on your computer, typically seen with a drive letter (e.g., `C:`, `D:`) or a mount point (e.g., `/home`).
Relationship	A volume is typically created on a partition. A simple physical disk can be split into multiple partitions, and each partition can become its own volume.	A volume can reside on a single partition (the most common case) or can be configured to span multiple partitions across different physical disks (using technologies like LVM or Windows Dynamic Disks).

Examples

A simple hard drive: An entire physical hard drive might have one main partition, which is then formatted to become the C: Volume. In this case, there is a one-to-one correspondence between the partition and the volume.
A USB flash drive: A floppy disk or a flash drive is often treated as a single volume even without being formally partitioned.
Multiple Drives (Logical Volume Management): You can take unallocated space from three different physical hard drives and combine them via software to create a single Logical Volume that appears to the user as one massive drive (e.g., a single 6TB D: Volume).

A logical volume is a portion of a physical volume. The video, Logical volumes, helps to illustrate the concept of logical volumes in data storage management.