These may be stored on separate disk volumes.

Installations could define additional private relocatable and source statement libraries on other disk volumes.

Said of a removable disk volume properly prepared for use --- that is, locked into the drive and with the heads loaded.

So two computers that access the same disk volume may know it by different LUNs.

This is needed when several clients are given block level access to the same disk volume.

Files may still span multiple disk volumes, however, now the list of volume names is given when the file is created.

Individual files do not span disk volumes.

The maximum size of a file is limited to the free space available on the disk volume where it resides.

Only one can be used to mount any given disk volume at any given time.

On a system with more than one disk volume, it is thus easy to create functioning backups of a system simply by dragging the folder.