A volume may refer to any of the following:
1.When referring to sound, volume refers to the amplitude of the sound being projected from a speaker. As seen in this picture, two knobs are used to change the volume level: one controls the Subwoofer, and one controls the main (overall) sound volume.
2.When referring to data storage, a volume refers to a logical drive, which has a single file system and is usually located on a single partition. For instance, on a typical Microsoft Windows computer, the volume named C: contains the operating system. In Windows, any drive which has an assigned drive letter is a volume.