Volumes

A single storage space within a computer, used to link multiple partitions together. The partitions can even stretch across different physical hard drives.

Features

Volumes are assigned a (usually) letter-based label e.g. C:\ to identify it.
Volumes contain directories (folders) which store files or even more directories, used to organize files in the storage space. Directories store access pointers to the files that are associated with it, so they take little space.
Further extensible with the usage of mount points when storage capacity becomes full.

There are different types of volumes in Windows that serve different purposes.

Basic Disks & Volumes

Contains primary partitions and extended partition with logical partitions in it. Can have up to four partitions, including an extended one. Accessible by almost any OS, including MS-DOS, Windows, and Linux.

Basic disks can only host basic volumes. Basic volumes are limited to only using partitions that are in the same basic disk; they cannot span multiple disks. To extend basic volumes,

Dynamic Disks & Volumes

Extends the functionality of basic disks & volumes by enabling the ability to span multiple partitions on multiple disk drives, and assign them under one volume addressable by Windows with a letter label.

Dynamic disks also enable the use of RAID disk arrays, which are incredibly powerful. They can support up to 128 volumes, and store partitioning information in a hidden database on all the dynamic disks in the system.

Extended Volumes

Extended volumes are another way to add space to the volume. When there are multiple partitions on the same physical drive, you can take some of the empty space allocated to the others and add it to one, extending the size of the volume you wish without losing data on the others.

Convert Volumes w/ DISKPART

Create a backup of the volume we're planning to convert in case of a failure. CMD > list disk CMD > select disk x CMD > create partition primary CMD > assign letter=[string|E] CMD > format fs=fat32 label=[string|"Backup"] quick

Begin the volume conversion process. CMD > convert /? CMD > convert E: /FS:NTFS